Legend Ti or Fierte Ti

[mikki]

My husband is suddenly in the market for a new bike as his current bike is shaking pretty violently at high speeds going downhill. Tried new wheels, checking headset, etc. and after spending some $$ has decided to look into a new rig.

He is a large guy and is pretty frugal, so I would like to pass on information about the comparison of the two bikes above. He asked me to find out what the forum thinks about the two bikes mentioned above. He loves both climbing and speed and feels best when getting the best bang for his buck.

Thanks for any input.

[jerk]

My husband is suddenly in the market for a new bike as his current bike is shaking pretty violently at high speeds going downhill. Tried new wheels, checking headset, etc. and after spending some $$ has decided to look into a new rig.

He is a large guy and is pretty frugal, so I would like to pass on information about the comparison of the two bikes above. He asked me to find out what the forum thinks about the two bikes mentioned above. He loves both climbing and speed and feels best when getting the best bang for his buck.

Thanks for any input.

try lowering the stem and putting some weight on the front wheel. you want bang for the buck? tell mr. mikki to learn how to ride a bike properly and i promise the violent shakes will disipate into the ether.

lower the handlebars, lengthen the stem and then try pointing the bike down hill. no one who has a normal racing bike with a normal racing bike position has ever experience this speed shimmy wobble thing....you said the mr. is frugal- so i'd recommend a normal racing bike position before he spends the big bucks on a a normal racing bike.

but then again i could be wrong and the goose neck could be injured....or the nut on the seat could be loose....

jerk

[e-RICHIE]

My husband is suddenly in the market for a new bike as his current bike is shaking pretty violently at high speeds going downhill. Tried new wheels, checking headset, etc. and after spending some $$ has decided to look into a new rig.

He is a large guy and is pretty frugal, so I would like to pass on information about the comparison of the two bikes above. He asked me to find out what the forum thinks about the two bikes mentioned above. He loves both climbing and speed and feels best when getting the best bang for his buck.

Thanks for any input.
mikki it's not always the equipment. zmatta fact the
culprit could be bad position and/or lack of confidence.
he may want to try to channel someone who's a good
bike handler/descender before he/you all throw money
at this. atmo, of course.

[jerk]

mikki it's not always the equipment. zmztta fact the
culprit could be bad position and/or lack of confidence.
he may want to try to channel someone who's a good
bike handler/descender before he/you all throw money
at this. atmo, of course.


are you reading my frucking mind again? don't make appoint you to the supreme court pal.

jerk

[e-RICHIE]

are you reading my frucking mind again? don't make appoint you to the supreme court pal.

jerk
descend this atmo.
the only reason you posted first is because
there's a tree down near my telephone pole.

[jerk]

descend this atmo.
the only reason you posted first is because
there's a tree down near my telephone pole.


yeah well there's a telephone poll down by my tree and i still beat you to the punch imho bro cheers....it's called wifi or weefee or something i pay $49.99 a month for so i earned it.


jerk

[Moosedryvr]

Mikki,
Not sure why your husband's bike is shaking so much on the downhills, especially if this is something that wasn't happening before. As was stated above, it may very well not be the bike. Often a high speed shake/shimmy is the result of the rider making an initial over reaction (however slight) to an input at speed, leading to the bike bucking all over the place as the rider tenses up on the controls and "gets behind the bike" by making more inputs to correct the situation (even subconciously) but in a manner that makes things worse rather than better. In the flying world we call these PIOs (pilot induced oscillations), reactive inputs by the pilot to an aircraft movement where the input, due to its tense and slighly delayed manner, make things worse rather than better. The results can be pretty amazing (read: scary as ****) and it takes a fair amount of training to learn to just relax and "freeze the stick" in an aircraft, the opposite of what your brain is telling you to do. On the bike the most effective reaction is usually to slow down some and relax, the relax thing being the opposite of what your natural reaction is.
It sounds like your husband has already had someone take a look at the bike to determine if it could be the problem and it also sounds like he's looking in the right places (headset seated and secure, wheels, especially front, trued and at the correct tension, bar/stem secure). Based on your relationship with Mr. Holland, I'd call him up and see if he'd take a final look at the bike (for a fee of course) to make sure its OK before I spent any more serious money on a new bike. I think I'd feel pretty sure the bike is OK if he was willing to take a look and give it the thumbs up. Finally, as also stated above, before I dropped several thousand on a new bike (unless that is what you really want in the first place) I'd try to find an accomplished descender to ride with me on one of the offending descents and evaluate my position/technique. It is damn hard to critique yourself on a bike and nearly imposssible to do so when you are concentrating on surivival due to a high-speed shimmy during a descent. This "objective observer" would be able to see things that your husband cannot and may in the end save a significant amount of money by suggesting something as simple as moving your husband's weight forward or back, or teaching him to "grip" the top tube with his knees, etc.
If it is the bike, I think you can find lots and lots of info here comparing Serotta Fiertes vs Serotta Legends by searching old posts. I've not had the pleasure of riding either bike but based on my time here I'll try to lay out the basics as I understand them. The Fierte is a great "value" bike (I have a hard time calling any $2400 frame/fork a "value bike", YMMV) in the Serotta line up. It comes only in Serotta's stock geometry, which tends to be higher in the headtube and lower in the bottom bracket than most "race" bikes sold today. The lower BB drop and the Fierte's slighly longer chainstays should make for a more stable bike, especially on the downhills. Additionally, the Ti versions of the Fierte are made with a lower grade (slightly heavier, less butting) of titanium than that of the Legend. The Legend is offered as full custom only, so you and the builders at Serotta can make it into whatever you want geo-wise and it offers Serotta's top of the line Ti tubeset. Nobody ever seems to have much negative to say about their Legend (they should be getting exactly what they ask for) although some say they can be a little too stiff if you're not careful in letting them know you want some comfort built into the frame.

My $.02.

Shawn G

[rwsaunders]

descend this atmo.
the only reason you posted first is because
there's a tree down near my telephone pole.

The Jerk (with friend) was recently spotted near ATMO's....

[dirtdigger88]

Mikki's Back!!!!
http://www.furfright.org/scrapbooks/2005/furfright2005scrapbook_files/image026.jpg

[Pete Serotta]

Mikki, glad to see you posting..This is a very good question that you asked -many have had or have the same type of problem. What the JERK and the "atmo" say is very good advice.

I have little knowledge in the area except to say most of the times it involves too little weight on the front end of the bike. Yes it can also be caused by the items you have addressed already, but since they have been eliminated you are left with the weight solution or a frame/fork problem.

As to a Fierte or a Legend, you mention that you husband is a big guy.....A fitting would be in order to determine what size he needs. Large frames or heavy duty frames are best addressed by custom, which either the Concours or Legend provide. If size and ride characteristics fall into Fierte specs, then it is a great ride also.

Another suggestion is to try a "demo" Fierte in his size and see if there is a wobble and if he likes the ride.

Good luck and let us know how things progress. PETE

[BumbleBeeDave]

Please pay no attention to those men behind the curtain . . . ! :rolleyes:

My first real "race" bike was a Vitus bonded aluminum frame I got in 1985. I had the same problem going downhill--oscillation that started and got worse and scared the whee out o' me! I had the wheel checked and the other stuff you've talked about and it still did the same thing.

Then somebody told me to just clamp the top tube between my legs whenever the problem started. So I did and--end of problem! I still do the same thing on downhills on my Legend and it seems to steady the bike, even though I know darn well from 6 years of riding my Legend that I don't need to. Some years later I was in a bike shop on vacation talking to the owner and I mentioned that I had a 979 Vitus. He replied, "How did you like the shaking?" I expressed surprise and he replied, "Oh, they all did that."

You don't mention exactly what kind of bike it is, but there's a chance it may not be the adjustments or your husband's riding skills. I just might be that brand and model bike. Or the combination of geometry and his weight and riding style--or any other of a dozen reasons. Be conservative and try the easy and cheap solutions first . . . have him do the clamp thing and see what happens. If it doesn't work, no loss. You can still get him a new bike if you want to! And BTW, oscillation is an officially accepted forum reason for "New bike!" . . . but by this time you've probably figured out that ANY reason is an officially accepted forum reason for "New bike!" :D ;)

Good luck!

BBD

[C5 Snowboarder]

mikki it's not always the equipment. zmatta fact the
culprit could be bad position and/or lack of confidence.
he may want to try to channel someone who's a good
bike handler/descender before he/you all throw money
at this. atmo, of course.

I am not sure about this theory.. take golf for example when my game goes into the toilet I always blame the equipment, I go buy new clubs and bang my game is back. thowing money towards new equipment also puts a smile on your face. It is always the equipment, same thing in snowboarding, it either a snowsnake that gets you to fall or the equipment. Man is never at fault unless of course it is relationship problems then it is always our fault.
:banana: :banana:

But back to the question -- go with the Legend. I am a proud happy big guy owner and all my good rides and hill climbs I owe to my wonderful riding Legend Ti.

[csm]

I fall when I snowboard 'cuz I am no good at it.

[Big Dan]

Get both....

:bike:

[C5 Snowboarder]

I fall when I snowboard 'cuz I am no good at it.

it is your equipment -- get a new board and then LESSONS :banana:

[Skrawny]

When I was purchasing my bike I had to decide between the legend TI and the Fierte (there was only one Fierte back then and it didn't have carbon seat stays). After a test ride, the winner was the Legend by a long-shot. However, this was a few years ago and it was with a different style Legend and a VERY different Fierte, so I cannot give any good advice between the two other than to reiterate the suggestion of a test drive and a good fitter.

I also had difficulty with high speed wobbles at two different times. Once it was because a little piece of something had imbedded itself in the rim of my front wheel; that time it was pretty obvious because it only happened when the front brake was on. The second time it turned out to be from my own legs shaking from the way I was "perched" on the peddles. Once I realized the source the problem it went away!

Good luck!
-s

[mikki]

I want to thank Shrawny, Moosedryvr, Serotta Pete and BBDave for your informative feedback. I will pass the info on to my husband. He is going to test out a Ti Serotta this next week from our favorite LBS.

FYI, my hubby is a cyclist of some twenty years and is excellent at it, so this sudden problem is not a function of being an ignorant rider as suggested by others here on this post. He thought the Serotta forum would be the best venue to hear other's feedback on info about the two Serotta's and perhaps someone else who'd had the same problem.

Thanks.

[e-RICHIE]

FYI, my hubby is a cyclist of some twenty years and is excellent at it, so this sudden problem <cut>

so - is/was this a new ride, or and older one
on which the issue suddenly surfaced atmo?





ps
arrange disorder
:p :p :p
:p :p :p
;) :p :p

[BumbleBeeDave]

Has he changed anything lately that might have created some new frame resonance or something? New wheels, stem, etc? If so, the best way to test might be to put the old stuff back on and see what happens. Also try the knees on the top tube trick--if it doesn't work you've lost nothing.

BBD

[Grant McLean]

FYI, my hubby is a cyclist of some twenty years and is excellent at it, so this sudden problem is not a function of being an ignorant rider as suggested by others here on this post.

Thanks.

Dear Mikki
I'm sorry you took some of the advice as a negative assessmen of your hubbies
skill. I'm quite sure that was not the intent.

Sadly, there is no simple answer to your question, in fact, "speed wobble" might be the
single most difficult phenomenon in cycling to understand the cause!
I have heard different explainations for almost 30 years, and there has
been no real study of the subject in cycling.

All I can add is that there are likely multiple factors (including the rider)
involved that come together all in one moment to make it happen.
Many cycling experts disagree on the cause, and it's not just bicycles that
can have this happen.

I suggest a google search:

http://www.google.ca/search?hl=en&q=speed+wobble&btnG=Google+Search&meta=


-g

[e-RICHIE]

Has he changed anything lately that might have created <cut>

BBD
mebbe it's holland envy atmo.
hey - that was levity.
insert this :beer: here: _____ .

[Moosedryvr]

mebbe it's holland envy atmo.



Now that's the best explanation of high-speed shimmy I've ever heard! :beer:
If my wife was riding around on a new Holland I'd be darn sure to find a reason to get something new and shiny! "Hey Babe, strangest thing happened to me today on my ride. All of a sudden my old and trusty ride is bucking like a bronco on descents! I think I might need a new bike..."
Let me know if this works and I'll see how it plays here in DC-town :rolleyes:

Shawn G

[Ti Designs]

Sadly, there is no simple answer to your question, in fact, "speed wobble" might be the
single most difficult phenomenon in cycling to understand the cause!
I have heard different explainations for almost 30 years, and there has
been no real study of the subject in cycling.


I'm trying to figure out if my study with MIT wasn't real or wasn't "in cycling". Harmonic motion with restoring factors isn't that hard to model or understand. As the rider controls the restoring constants (forces on wheels, saddle, pedals and bars), you can see why many think it's pilot error. There are two tubes in torsion during speed wobble, if their harmonics are the same it can set up an additive wave, so there are bikes where speed wobble can be induced. If the harmonics are far enough off, they will quickly become out of phase and cancel the wobble. It's far more common for the torsional harmonic of the top and down tubes to be different, so relativly few frames shake until the rider comes to a full stop. Just the same, some frames do this - call it luck! (no, there will be no study on luck)

[e-RICHIE]

thread drift kinda sorta -


As the rider controls the restoring constants (forces on wheels, saddle, pedals and bars), you can see why many think it's pilot error.

did your study unearth a case for shakes/wobble/oscillation
from among the pro ranks - that is, guys that spend a work
day upon the same bicycles we all ride?

[Ti Designs]

did your study unearth a case for shakes/wobble/oscillation
from among the pro ranks - that is, guys that spend a work
day upon the same bicycles we all ride?

Any pros you know of ride an early 62cm Legend Ti? I sold an expensive frame to a guy who knows how to ride and once it started to shake it didn't stop until the bike did. I asked a few people in the bike industry and they all thought it was black magic - change the front tube, kill a chicken, mutter these words in latin... I have plenty of friends at MIT, so we made a computer model of the frame with parameters for the restoring or damping factors. We came up with two conclusions, the frames that shake until they stop are very rare - you probably couldn't build one if you tried. Just the tolorance in where the butted sections start and end can make the difference. And the induction of the wave must be greater than the normal damping forces - that's up to the rider. if you really want to make a test case, leave the top tube out of a frame, take out a bunch of life insurance and go for a ride. You can probably ride it all day long, staying in the saddle, and never have a problem. Try getting out of the saddle and it starts looking like one of those swing bikes from the 70's without the pivot. It's still not an additive wave, so the period will be long and the frequency low, but you get the idea.

[Fixed]

bro sounds like a job for myth busters
imho cheers hicup :beer:

[chrisroph]

I was in a bike shop on vacation talking to the owner and I mentioned that I had a 979 Vitus. He replied, "How did you like the shaking?" I expressed surprise and he replied, "Oh, they all did that."


BBD

I had a pink one that didn't. It was great for STP and To Hell 'N Beyond but I sold it and bought a ciocc for racing.

[e-RICHIE]

<snipped> but you get the idea.

actually - no. this issue confounds me. the same bicycles and designs we
all use are co-opted in the pro ranks, and i never heard of this phenom
there. until futher notice, i'm still leaning on the thought that we all have
a comfort zone, and once we leave it, we may have that personal jesus
moment atmo.

[Ti Designs]

bro sounds like a job for myth busters


They bring their questions to the same people...

[Fixed]

but then again i could be wrong and the goose neck could be injured....or the nut on the seat could be loose....
bro mr. jerk cracks me up
cheers


legend is a legend get one if you can

[mikki]

This is getting more interesting as it unfolds.

OK. So I laughed out loud at the "HOLLAND ENVY" possibility. Although I do acknowledge that as a definate possibility, I saw the expression on his face after a very fast descent that we did together. Needing to clarify further, the shimmy is only pronounced on descents apparently. And there is a pulling to one side or the other that is going on also that I didn't know about until he mentioned it this evening. The LBS looked at the headset and said that all was fine.

Could it be something gone awry in the fork?

He would really rather spend little $$ and get this corrected if it can be corrected, but the trusted LBS couldn't figure it out. I would love to see him on an awesome bike like my beloved Holland (650 happy miles logged), but he is the frugal one so would prefer fixing this one.

[e-RICHIE]

This <cut>.
atmo - (http://serotta.com/forum/showpost.php?p=390170&postcount=18)

[Fixed]

buy it for him surprise early christmas ... birthday ....imho
cheers hicup :beer:

[e-RICHIE]

buy it for him surprise early christmas ... birthday ....imho
cheers hicup :beer:
another holland in the stable?
that'd be double dutch atmo.








ps
arrange disorder
:D :D ;)
;) :) ;)
;) :D :D

[Serotta_James]

First three things we check in a front end instability problem:
1) Front wheel
2) Fork
3) Rider weight balance

[gary135r]

I want to thank Shrawny, Moosedryvr, Serotta Pete and BBDave for your informative feedback.
Hey, where is the luv for E-Richie and Jerk. we need a group hug.

[Ti Designs]

actually - no. this issue confounds me. the same bicycles and designs we
all use are co-opted in the pro ranks, and i never heard of this phenom
there. until futher notice, i'm still leaning on the thought that we all have
a comfort zone, and once we leave it, we may have that personal jesus
moment atmo.


So you can take two springs of equal harmonic (same frequency and period), put a mass between them, get the motion going and it goes almost forever or until you stop it. You can take two springs of unequal harmonic and do the same thing, they come out of phase and cancel out the motion. Yet when the two springs are the torsion of the top tube and down tube you blame jesus?

OK fine, get yourself two frames - I'm sure you have one or two kicking around. Take a frame that has a known speed wobble (the kind that doesn't stop until the bike comes to a full halt). Lock the bottom bracket down to the flat table and anchor the seat post in place. Now put a long extension bar into the head tube and put a weight on either end sticking out. You now have two springs and a mass. Give one of the weights a push and watch the system oscilate - also notice that it probably stops pretty quickly. Now do the same with the frame with the speed wobble. If it stops by itself in about the same number of cycles, it's the rider. If it keeps going you've either found your speed wobble or it's time to glue a fish onto the bumper of your car.

[Moosedryvr]

i'm still leaning on the thought that we all have
a comfort zone, and once we leave it, we may have that personal jesus
moment atmo.

+1 on this. I've had high-speed shimmy happen to me before on a bike that never gave me a problem before, scared the living crap out of me and I pretty much went through a set of brake pads getting off the mountain from that point on, but it doesn't happen every time I descend at that speed on that bike.
I have little doubt that one could prove that a specific bike could be a bad apple and cause this as TiDesigns suggests. However, my flying experiences totally lead me to think that in most cases it is "pilot" induced. I taught hundreds of guys and gals to air refuel the C-17 (the Moose in Moosedryvr) during my last assignment. I bet every third one of them got into the aircraft equivalent of a high-speed shimmy at one point during that training; gettting two very large aircraft ~18 feet apart so one can stick a fuel nozzle into the other can be a little nerve wracking at times, especially at night or in bad weather. No matter how smooth they thought they were being, it is very difficult to truly relax when you are trying to squeeze juice out of an aircraft control stick/throttes (or a bicycle handlebar). IMO, being relaxed/comfortable is key to eliminating this shimmy. Let's be honest, how many of us are really comfortable screaming down a hill at 40+ mph, especially on a twisting descent? I'll bet those of us who are (such as the pros as e-Ritchie suggests) have little problem with this phenomenon. Getting comfortable in this situation (and while refueling an aircraft at 25,000') is a matter of exposure and practice. Add lots of those two things and I bet this shimmy thing will go away. Could it be the bike, you bet. Do I think it is (if the bike is fit correctly)? I doubt it. YMMV.

Shawn G

[e-RICHIE]

So you can take two springs of equal harmonic (same frequency and period), put a mass between them, get the motion going and it goes almost forever or until you stop it. You can take two springs of unequal harmonic and do the same thing, they come out of phase and cancel out the motion. Yet when the two springs are the torsion of the top tube and down tube you blame jesus?

OK fine, get yourself two frames - I'm sure you have one or two kicking around. Take a frame that has a known speed wobble (the kind that doesn't stop until the bike comes to a full halt). Lock the bottom bracket down to the flat table and anchor the seat post in place. Now put a long extension bar into the head tube and put a weight on either end sticking out. You now have two springs and a mass. Give one of the weights a push and watch the system oscilate - also notice that it probably stops pretty quickly. Now do the same with the frame with the speed wobble. If it stops by itself in about the same number of cycles, it's the rider. If it keeps going you've either found your speed wobble or it's time to glue a fish onto the bumper of your car.
ti you lost me.
i'll rephrase this (http://serotta.com/forum/showpost.php?p=390203&postcount=28) - do you have any anecdotal information
in the pro ranks regarding this phenomenon atmo?

[mikki]

Thanks everyone. (and i do mean everyone who responded). We are going out for a few hour ride right now. I passed on all this information to him so we will see what happens.

As his bike is not the top of the line of it's brand (close) and it IS four years old, if this proves to not be rider-induced and it turns out to be the bike, I can only hope he will opt for a better bike this time. He is scheduled to test the Legend this week. I bet that bike will do a good job of enticing him to a custom.

Thanks again.

[e-RICHIE]

As his bike is not the top of the line of it's brand (close) and it IS four years old, <cut>

Thanks again.
so - (http://serotta.com/forum/showpost.php?p=390170&postcount=18)

[davids]

I'm still waiting for an answer to this question:

"so - is/was this a new ride, or and older one
on which the issue suddenly surfaced atmo?"
If the bike has always behaved this way, I'd be more tempted to look for a new frame.

If it's started happening recently on a bike he's been riding for a long time, I'd be inclined (...) to think it's the rider, and that a change in position/stem/etc. would definitely solve it. Mikki's reference to this as a "sudden problem" suggests this is the case.

This second option, by the way, is precisely what was suggested by the jerk and e-RICHIE.

[dirtdigger88]

so - (http://serotta.com/forum/showpost.php?p=390170&postcount=18)

careful- you are not giving mikki the answer she wants- :no:

Jason

[Dave B]

Could a road tire get a flat spot like a car tire?

If you were speeeding big time and locked up the wheels to induce a sweet skid like we used to when we were kids, would it develope a flat spot? Could that affect the shimmy you speak of.

if nothing has "happened" to the bike during a ride, couldn't it be the sum of something?

Could a carbon fork have fractures inside it without it showing on the pretty finishing layer.

could the bearings be THAT pitted in the hubs?

I don't know I am reaching.

How big is the bike? If he gets a new one I'll take the old one woblles and all.....for free of course.

[benb]

I bet you could find video tape of it happening in the pro ranks.

There are way too many stories of it happening to experienced riders for it to be totally the riders fault.

I've seen some very good riders get it on bikes that had a lot of weight on the front wheel. My opinion at the time was that was caused by tire pressure issues & tenseness in the rider. (Rainy conditions) My friend had it on his litespeed so bad with the right tire pressure on this one particular occasion that it would start at like 10mph.

Motorcycle geometry is extremely stable in comparison to bicycles & rider weight positioning is a smaller component then on a bicycle and yet motorcycles will also do it. (Mostly having to do with the front wheel getting light under power and a side force being generated on the front wheel.) With the right tire/pressure/load I've seen it happen moderately on my motorcycle when I was *off* the gas, which cause a big shift forward in weight... and my bike is not agressive at all, nor does it exhibit the problem if the front wheel gets light.

My MTB did it for ~1 second last week going up a slight incline when I put the hammer down and the front wheel got light and hit a bump.

Luckily I've never experienced the terminal type where the oscillation builds. :)

[BumbleBeeDave]

Try the clamping the top tube between his legs trick first. If only in the short term, it might help.

But whether it helps or not, if you've changed anything on the bike lately, then change it back--one thing at a time--to see if you can isolate the cause of the problem. You can't do anything until you know what's causing it.

If your husband has been riding for years, then barring any sudden change in his biomechanics from injury or other cause, I'd not select "operator error" as a first choice for causes.

BBD

[93legendti]

ti you lost me.
i'll rephrase this (http://serotta.com/forum/showpost.php?p=390203&postcount=28) - do you have any anecdotal information
in the pro ranks regarding this phenomenon atmo?

Do the pros ever complain publicly about the shortcomings of their sponsored equipment?

[e-RICHIE]

If your husband has been riding for years, then barring any sudden change in his biomechanics from injury or other cause, I'd not select "operator error" as a first choice for causes.

BBD
then what's on the list?

[e-RICHIE]

Do the pros ever complain publicly about the shortcomings of their sponsored equipment?
that's a separate issue atmo.
if what we are discussing here ever happened, i am
sure it would make a race report or a film at eleven.

[93legendti]

that's a separate issue atmo.
if what we are discussing here ever happened, i am
sure it would make a race report or a film at eleven.

You lost me.

You stated:

actually - no. this issue confounds me. the same bicycles and designs we
all use are co-opted in the pro ranks, and i never heard of this phenom
there. until futher notice, i'm still leaning on the thought that we all have
a comfort zone, and once we leave it, we may have that personal jesus
moment atmo.


You asked:

ti you lost me.
i'll rephrase this (http://serotta.com/forum/showpost.php?p=390203&postcount=28) - do you have any anecdotal information
in the pro ranks regarding this phenomenon atmo?

I answered:

Do the pros ever complain publicly about the shortcomings of their sponsored equipment?



You say they are seperate issues. I do not see the disctinction. FWIW, I think the photogs on the back of motorcyles descending mountain passes at up to 100kph might not be focusing upon riders' TT's for the entire descent trying to capture TT shakes/wobble/oscillation/shimmy ("shimmy").

So, I will rephrase: Can you tell me the name of a pro who has publicly stated that there was a problem with his sponsored equipment? If not, then your claim that we have not heard about TT shimmy in the pros and, thus, it must be a rider error issue, seems based upon a faulty premise.

[e-RICHIE]

So, I will rephrase: Can you tell me the name of a pro who has publicly stated that there was a problem with his sponsored equipment? If not, then your claim that we have not heard about TT shimmy in the pros and, thus, it must be a rider error issue, seems based upon a faulty premise.
my post and question was to ti and
directly related to the work he cited
at MIT. (http://serotta.com/forum/showpost.php?p=390193&postcount=24) but, no - i cannot tell you
the name of a pro...

but no matter how we twist this around, i have followed
racing since the 70s and have seen 100s of hours of tape,
and have never heard of this phenom happening in the pro
ranks. and that, adam, is my point. we all ride the same
stuff, yet the few times this issue arises, it comes from
the sidelines.

[Grant McLean]

my post and question was to ti and
directly related to the work he cited
at MIT. (http://serotta.com/forum/showpost.php?p=390193&postcount=24) but, no - i cannot tell you
the name of a pro...

but no matter how we twist this around, i have followed
racing since the 70s and have seen 100s of hours of tape,
and have never heard of this phenom happening in the pro
ranks. and that, adam, is my point. we all ride the same
stuff, yet the few times this issue arises, it comes from
the sidelines.

There are several pros who routinely grip their top tube with their knees
crossing the finish line with their arms in the air. (Thor Husholvd comes to mind)

The Jobst Brandt (http://www.sheldonbrown.com/brandt/shimmy.html) article points out
not having your hands on the bars can increase the chances of a wobble.


g

[e-RICHIE]

There are several pros who routinely grip their top tube with their knees
crossing the finish line with their arms in the air. (Thor Husholvd comes to mind)

The Jobst Brandt (http://www.sheldonbrown.com/brandt/shimmy.html) article points out
not having your hands on the bars can increase the chances of a wobble.


g
hey - thanks atmo.

[J.Greene]

My common sense tells me that a 170lb or so body would have more to do with how a bike wobbles than how 16 lbs of carbon, ti, alu or steel could make a rider wobble.

JG

[Pete Serotta]

Mikki, let us know if the SEROTTA or another demo bike that he rides does the same thing.

As some have said ....if he clamps his legs against the top tube see if wobble continues on his bike. I am sure that folks did not mean his experience level as a rider was low - - the wobble, when I have had it, was the result of me being too far back on the seat and un weighting the front end......

ALso, I wanted to send you a note but it said you forum mail folder was full.

Have a good week and I will try that "red" you recommended... PETE

[e-RICHIE]

I am sure that folks did not mean his experience level as a rider was low - - the wobble, when I have had it, was the result of me being too far back on the seat and un weighting the front end......


says it all atmo cheers -


ps
http://designtree.files.wordpress.com/2007/06/red_candy.jpg

[Fixed]

bro when i'm scared I shake ..imho
cheers

[Pete Serotta]

RED is good for "un scaring"


bro when i'm scared I shake ..imho
cheers

[93legendti]

my post and question was to ti and
directly related to the work he cited
at MIT. (http://serotta.com/forum/showpost.php?p=390193&postcount=24) but, no - i cannot tell you
the name of a pro...

but no matter how we twist this around, i have followed
racing since the 70s and have seen 100s of hours of tape,
and have never heard of this phenom happening in the pro
ranks. and that, adam, is my point. we all ride the same
stuff, yet the few times this issue arises, it comes from
the sidelines.

Sorry for intruding, I thought my post and question were directly related to your posts.:)

[J.Greene]

RED is good for "un scaring"

Is drinking red and cycling an official Serotta position? :beer:

JG

[Pete Serotta]

Cycling is the "official SEROTTA position - do lots of it..
________________________________________________
As to drinking red, it is an official PETE, FLYDHEST, MARK S and Tom Brynes social position. We do it in moderation and do not drive or ride after having our two glasses. BUT WE DO ENJOY IT and the conversation.
_________________________________________________
I do not speak for SEROTTA, am not endorsed by them, and am not paid by them. I volunteer my time in trying to assist in keeping the forum in a mild state of chaos. ;)

I do not mean to offend by talking about wine - and apologize if some have taken offense.

AND I think most would rather hear about it than my trip to the dentist or to the IRS :D




Is drinking red and cycling an official Serotta position? :beer:

JG

[e-RICHIE]

Sorry for intruding, I thought my post and question were directly related to your posts.:)
well that's why i answered you question atmo. are you trying to catch me
out on something? i'm adding my information based on experience, and i've
posted regularly that i am stymied wrt how this issue seems at home on some
sidelines when - oddly - i've never seen it among folks whose paychecks
depend upon an ability to be relaxed at speed no matter that they've never
been on a certain course and/or in certain conditions. it confounds me.

[malcolm]

I think the distinction in what Ti designs is talking about is a bike that shimmies until it is brought to rest/stopped. Most of the bike shimmy problems I've heard of stop before actually stopping the bike and these are usually, by most people felt to be caused by rider input. I tend to grip the top tube when ridding hands free because it helps me stay in a straight line if not pedaling. If I'm continuing to pedal it is not a problem but sometimes coasting hands off I'll drift to one side. Just a thought.

[J.Greene]

AND I think most would rather hear about it than my trip to the dentist or to the IRS :D

I was just pulling your leg a bit.

JG

[Pete Serotta]

Proper bike position and bike fit have lots to do with a stable ride.......I think the pros have both of these in large quantity.

Additionally no one has MORE miles to perfect their position and ride in all circumstances than PROs or PRO want to bes.... :bike: :bike:

I am a "want to be" that is still perfecting my position and ride via folks like Mr Sachs, David Kirk, Curt Goodrich. AND NATURALLY MR MIKE GROTZ from CYCLESPORT!!! :D ;)

[Fixed]

bro i was at the beer shop the other night had on my imperfection is perfection t shirt and the clerk liked it so much she almost ripped it off me .sat night my wife my fix and my beer nothing gets much better in my life imho
she didn't get my shirt either .

[Pete Serotta]

You brought up a good point though,,,,,,THANKS


I wish I could get rid of the "SEROTTA PETE" and go back to PETE MCKEON (ANDREW did that to me :confused:)


Thanks

I was just pulling your leg a bit.

JG

[vaxn8r]

Do the pros ever complain publicly about the shortcomings of their sponsored equipment?
Lance complained about his TT bike.

Boonen wasn't happy about his Specialized this yearr or his Time last year.

Heck, how many pro's used to refuse to ride their sponsor's bikes? That's how Calfee and Litespeed used to have bikes ridden in the Tour.

I think pro's complain a lot about equipment.

[C5 Snowboarder]

Lance complained about his TT bike.

Boonen wasn't happy about his Specialized this yearr or his Time last year.

Heck, how many pro's used to refuse to ride their sponsor's bikes? That's how Calfee and Litespeed used to have bikes ridden in the Tour.

I think pro's complain a lot about equipment.

I would agree and this would be in any sport. Auto racing , golf , snowboarding, to name a few. Tiger had some exceptions on Nikes equipment if it would not perform he did not have to play it, snowboards that built by other builders but carry other sponsor manufacturers brand markings,
Pro's complain for real complaints to non- existant complaints and issues. Shimmy and wobble in bikes I am sure have been common issues and are dealt with and fixed but I also realize they are professional and probably ride and can handle problems we do not want to. Look at a NASCAR race some day -- you think we'd put up with the rumble , shaking, steering wheel shake and hop and ect they do .. Heck no we'd complain to everyone that the Chevy shakes at high speed.

[J.Greene]

I think pro's complain a lot about equipment.

Maybe, but has anybody ever heard a pro said he could not get it done at the business end of a race because his bike shimmied? I'm sure someone faster than me would know.

JG

[vaxn8r]

Maybe, but has anybody ever heard a pro said he could not get it done at the business end of a race because his bike shimmied? I'm sure someone faster than me would know.

JG
Yeah, that's my point. If it were happening, I think we'd be hearing about it. That was Boonen's entire beef. He didn't like the way his Time and Specialized were getting him to the line iircatmo

[Ti Designs]

ti you lost me.
i'll rephrase this (http://serotta.com/forum/showpost.php?p=390203&postcount=28) - do you have any anecdotal information
in the pro ranks regarding this phenomenon atmo?

So much for scientific testing...

If you're going to use that logical error as the basis for argument, has anyone seen both Ben Serotta and the Easter Bunny at the same time - I have a theory...

[e-RICHIE]

So much for scientific testing...

If you're going to use that logical error as the basis for argument, has anyone seen both Ben Serotta and the Easter Bunny at the same time - I have a theory...
why don't you have MIT do another scientific test for that atmo?

[dirtdigger88]

I dont think Ben is the Easter Bunny . . .

http://www.sherbetmoon.com/shopimages/products/thumbnails/317Pinkcopy.jpg

jason

[BumbleBeeDave]

then what's on the list?

. . . would be something on the bike that has changed, and in the process has changed the entire structure's resonance frequency. I don't claim to be any engineering expert, but I do recall having read that every structure has a resonance frequency--as I think TiDesigns pointed out already--and that designing to damp that frequency is a crucial component in things like bridges and tall buildings. Anyone who's ever watched that old movie of the Tacoma Narrows bridge jumping around and then flying apart in the 1940's knows that avoiding letting that frequency get out of control is a very good thing! :eek:

I lean toward a component of the bike rather than the rider's form or technique because in my own experience my own technique has never changed radically in a short period of time. I don't think Mikki's husband's technique would change so drastically either--unless he got something like a new saddle that forced him to slide back, for instance. But in that case the original change would still be associated with the structure of the bike rather than the technique of the rider.

But I think we should be practical here. This is all so easy to test. Mikki's husband could just go out and ride down a hill and feel the bike wobble--keeping his legs ready to clamp that top tube if needed for damping. Then ride down the hill again and slide farther forward on the seat and bars. Does it still wobble? Does the feel of the wobble change? When it starts? How quickly it increases? If so, then a reasonable argument could be made that it does have to do with his riding technique. BUT it could still be that his technique has changed in response to some change in the bike--new bars, a shorter stem, a new saddle, etc.

But that's easy to check, too. Just sit down and take stock of EVERY change that's been made to the bike lately . . . any new parts, new brake pads, wheel bearings recently adjusted--anything. Even adjustments made that were just tightening or loosening of screws such as the seatpost collar, water bottle screws, etc. I'd be willing to bet if you sat down and made that list and then went out and did some testing with adjustment or removal of various screws or parts in question, that this cause could be isolated and the wobble eliminated. After all, she says his bike is shaking, but I've seen nothing about it shaking the whole time he's owned it. So obviously something's changed that is causing it. I just think it's more likely the structure than the rider technique and that he and Mikki just need to do some more experimenting to isolate what it is and correct it.

UNLESS, or course, he just wants a new bike--and that's OK, too! ;)

BBD

[e-RICHIE]

she says his bike is shaking, but I've seen nothing about it shaking the whole time he's owned it.


BBD
i feel ya bro atmo.




ps
arrange disorder
:cool: :rolleyes: :cool:
:rolleyes: :cool: :rolleyes:
:cool: :rolleyes: ;)

[Pete Serotta]

I heard and saw the Bee Machine as it passed me.... :p


i feel ya bro atmo.




ps
arrange disorder
:cool: :rolleyes: :cool:
:rolleyes: :cool: :rolleyes:
:cool: :rolleyes: ;)

[SPOKE]

bro when i'm scared I shake ..imho
cheers

I shake when I get cold.....and i have been cold enuf on some very fast (45+mph) dessents that my shivers induced the dreaded "speed wobble" (in motorcycle racing we call it a "tank slapper"). Pinching the tt with my knees stopped it. Sliding forward a bit stopped the second time.

[e-RICHIE]

I shake when I get cold.....and i have been cold enuf on some very fast (45+mph) dessents that my shivers induced the dreaded "speed wobble" (in motorcycle racing we call it a "tank slapper"). Pinching the tt with my knees stopped it. Sliding forward a bit stopped the second time.
'happened to me at jiminy peak (http://serotta.com/forum/showpost.php?p=251760&postcount=14) atmo.
cold and wet.

[mikki]

Here is more input from my husband.

More annoying and scary than the shimmy apparently, is the strong pulling to the left or the right that I mentioned in an earlier post. He further discribes it as if he were holding a gyroscrope that is out of balance. Remember, we have tried replacing the wheels, looked at the headset, all okay. With what everyone is saying, maybe the PULLING is what is causing his position to change, consequently causing the shimmy. Furthermore, this pullling has been a part of the bike since a tune-up about a year and a half or longer ago. No parts were changed at that time. Since then he has changed his handlebars and stem. Didn't increase or decrease the pulling. The shimmy is new.

After reading all of your comments, I suspect the shimmy is rider caused. I bet if we could correct the pulling, his compromised position would be corrected too.

The bike is carbon. Does carbon fatigue? Could that somehow be a culprit in any of this?

[davids]

The pulling is "to one side or the other", not to one specific side?

I'm out of ideas.

[tch]

how about dishing issues on the front wheel? Did someone "true" his wheel but really pull it out of round longitudinally?
Or some kind of fork/skewer misalignment?
Or some kind of tire mount issues? Check tire to see if it is still seated. AND, check to see that it is not compromised somehow. I've had car tires that delaminated in the inner belts: looked fine on the outside, but squirmed something fierce when put up to speed with a load.

[e-RICHIE]

Here is more input from my husband.

More annoying and scary than the shimmy apparently, is the strong pulling to the left or the right that I mentioned in an earlier post.
i missed that.



He further discribes it as if he were holding a gyroscrope that is out of balance. Remember, we have tried replacing the wheels, looked at the headset, all okay. With what everyone is saying, maybe the PULLING is what is causing his position to change, consequently causing the shimmy.


sounds plausible atmo

Furthermore, this pullling has been a part of the bike since a tune-up about a year and a half or longer ago. No parts were changed at that time. Since then he has changed his handlebars and stem. Didn't increase or decrease the pulling. The shimmy is new.
hmmm. did he save the tune-up receipts?

After reading all of your comments, I suspect the shimmy is rider caused. I bet if we could correct the pulling, his compromised position would be corrected too.
mebbe it needs a tune-down.

The bike is carbon. Does carbon fatigue? Could that somehow be a culprit in any of this?
i know a cat who can answer that:

http://farm2.static.flickr.com/1163/749884200_77fe68ee2d.jpg


mikki-issimo in all seriousness i think the best advice is
to get another bicycle, hopefully one of the serottas, and
begin to unring this bell of uncertainty. somewhere here
this is a mental block and the best antidote is working that
amex card. seriously atmo.

[Richard]

I've seen peoples bikes "pull" or tend to turn with hands off the bars as a result of unequal cable housing lengths causing the pressure on the bars to turn one way or the other. Seems more pronounced on Campy because of the location under the tape. It is not usual, but it does happen. Seems more likely than a four year old bike "wearing out." That it began after a tune up may be telling.

[vaxn8r]

So if the bike is "bad", are you going to sell it to someone else?

[weaponsgrade]

Have others tried riding the bike and experienced the same thing? That might help in trying to diagnose whether the problem is equipment or rider related. Apologies if this has already been asked. I didn't read the entire thread. Back to your original question. I have a custom Classic Ti which was several generations before the Fierte Ti. At the time I bought my Classic Ti I test rode a Legend and could not tell a difference. The one time I experienced shimmies was descending a pass in the Sierras where I swerved/braked to avoid a rider in front of me that was experiencing a really bad case of the speed wobbles. Since then I've put on many thousand more miles, hit a top speed of 55.5mph and no shimmies. I'd suggest trying to take both bikes out on a test ride to see if you can tell a difference. I've been very happy with my decision. I'll admit that every now and then I suffer an inferiority complex and wish I had gotten the Legend for the simple fact that because it was more expensive it must've been "better".

[mikki]

The pulling is "to one side or the other", not to one specific side?

I'm out of ideas.

He answered your question by saying "all over the road. Left, right, left, right"

Good idea to have the LBS ride it again. My husband is going to suggest that the test ride be by someone nearer his dimensions. The mechanic who is much smaller than my husband, rode it and couldn't get it to pull. So that seems to say something to weight being a factor.

Didn't keep the receipts of the original tune up that seemed to preceed this; though we should have. It was NOT at our favorite bike shop, but up in Orange in a shop that comes well recommended. Hmmmm. It does seem suspect!

Ah well, I think we might have exhausted possibilities here. Thanks everyone; your ideas were appreciated.

Christmas is fast approaching. Maybe Santa will see that he's been very good this year and have a wonderful new bike waiting for him on Christmas morn!!

[Fat Robert]

your answer

rolland della santa

tell hubby its worth the weight

[Big Dan]

Come on, you don't need more than one excuse to get a new steed....
Time to breakout the 401K.........


:p

[Bud_E]

mikki-issimo in all seriousness i think the best advice is
to get another bicycle, hopefully one of the serottas, and
begin to unring this bell of uncertainty. somewhere here
this is a mental block and the best antidote is working that
amex card. seriously atmo.

Very often this is my course of action when I experience something similar. Even if it doesn't really solve the problem, I feel I've done something proactive so I get the endorphin effect and I am blissful for several hours.

[e-RICHIE]

Very often this is my course of action when I experience something similar. Even if it doesn't really solve the problem, I feel I've done something proactive so I get the endorphin effect and I am blissful for several hours.
and it's all downhill from there, hopefully sans shimmys atmo.

[Louis]

The bike is carbon. Does carbon fatigue?

Not really. Not in the same as steel, Al or Ti. Doesn't mean you can't get failure due to static overload, or other "pseudo fatigue" failures (stuff like matrix failure, delamination or degradation due to environmental issues), but in general, no, CF is very, very good in fatigue.

[Fixed]

bro it just snaps it doesn't waste time imho
cheers :beer:

[BumbleBeeDave]

how about dishing issues on the front wheel? Did someone "true" his wheel but really pull it out of round longitudinally?
Or some kind of fork/skewer misalignment?
Or some kind of tire mount issues? Check tire to see if it is still seated. AND, check to see that it is not compromised somehow. I've had car tires that delaminated in the inner belts: looked fine on the outside, but squirmed something fierce when put up to speed with a load.

I would also wonder about the truing, dishing, wheel bearing adjustment, etc. It might also be a problem with the tire. I know I've had problems like that with the tires on my car when they get worn down. Not-quite-perfect balancing early in the tire life has created scallops of other surface features on the tire that don't show up until I would get to highway speed, or between 50-60 mph, etc. But then the pulsing or pulling would get quite pronounced.

As one other has suggested, I would get someone else similar in stature to hubby to ride the bike and see if the same wobble appears. Another easy test would be to put somebody else's front wheel on the bike and see if the wobble disappears. But only Mikki and her hubby can decide when it's no longer worth the diagnostic trouble and just go for a new bike.

BBD

[rounder]

bro it just snaps it doesn't waste time imho
cheers :beer:

That was good. cheers.

[rwsaunders]

Very often this is my course of action when I experience something similar. Even if it doesn't really solve the problem, I feel I've done something proactive so I get the endorphin effect and I am blissful for several hours.

+1. Dr. Phil would sense the hidden envy on the part of your husband regarding your Holland purchase. Simply because of your husband's self-proclaimed frugalness, he can't openly admit his inner feelings for a new bike. So much anxiety.

On another note, I thank your husband for the script, as I'm going to try it out on my lovely bride. :cool:

[andy mac]

a question that may have been covered off but i'm going too cross eyed to read everything - does it happen under braking? or, when he's running free?

maybe the brakes are causing it? my old '65 falcon coupe' with drum brakes would pull to the side. pads? cables? set up?

never had the speed wobbles on a bike but i've had some good ones on a skateboard in the past. have also driven behind a car towing a caravan that got 'em at speed. quite scary.

:beer:

[mikki]

a question that may have been covered off but i'm going too cross eyed to read everything - does it happen under braking? or, when he's running free?

Happens when running free.

Bumblebee Dave, we tried replacing the whole wheel and tire, to no avail.

I think we'll look into seeing if the cables are all fine, look at the fork and have someone of his stature ride it to see if we can find the cause of the pulling. IMO the wobble was created by his own reactions while trying to compensate for the pulling left and right.

RWSaunders, don't know you or how you and your wife interact, but my hubby wouldn't find it necessary to make up such a story, feign being nervous etc. He could have simply ordered himself any bike he wanted without saying a peep to me (if he didn't want to), if this was about being jealous of my new bike.

Thanks for your input. I look forward to seeing what he decides to do.