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Old 03-10-2017, 06:58 AM
stephenmarklay stephenmarklay is online now
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Help fitting a smaller bike

For reference I am about 5’11.75” and shrinking.

I normally ride a comfortably a 57cm. I have ridden frames as small as 56 and as large as 58cm. I mostly look at the top tube and headtube for level top tube bikes.
I have find that about a 127mm (nitto pearl) stem on a 57cm is right and now I am running a nitto noodle. That combo is a tad long for.

I am contemplating buying a bike that is a 55cm top tube and my question is how much is too much for weight over the front. Looking at bar/stem combos

I could replicate my “ideal” torso position with a the nitto pearl 120 (127) and the Compass Maes Parallel Handlebar. This is shallow drop also which is nice since the headtube is a wee but shorter 0.5-1.0cm less than normal.


I have seen lots of folks my size say they ride a 55cm and when I look at those old Lemond charts it puts me on a 55.5cm

Thanks so much.

Last edited by stephenmarklay; 03-10-2017 at 07:32 AM.
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Old 03-10-2017, 08:29 AM
sokyroadie sokyroadie is offline
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If you like compact bars this will help with the shorter HT.

https://www.specialized.com/us/en/eq...mm-rise/118174

I have seen them on a bike and they look fine.

FWIW - I am 5'7" and ride a 55 TT frame - good luck making it fit.

Jeff
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Old 03-10-2017, 08:34 AM
OtayBW OtayBW is offline
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Quote:
Originally Posted by stephenmarklay View Post
For reference I am about 5’11.75” and shrinking.

I normally ride a comfortably a 57cm. I have ridden frames as small as 56 and as large as 58cm. I mostly look at the top tube and headtube for level top tube bikes.
I have find that about a 127mm (nitto pearl) stem on a 57cm is right and now I am running a nitto noodle. That combo is a tad long for.

I am contemplating buying a bike that is a 55cm top tube and my question is how much is too much for weight over the front. Looking at bar/stem combos

I could replicate my “ideal” torso position with a the nitto pearl 120 (127) and the Compass Maes Parallel Handlebar. This is shallow drop also which is nice since the headtube is a wee but shorter 0.5-1.0cm less than normal.


I have seen lots of folks my size say they ride a 55cm and when I look at those old Lemond charts it puts me on a 55.5cm

Thanks so much.
I'm 6ft and 57 cm square would be too big for me, personally. It's possible, but not optimal. I ride 55 or 56, but usually prefer to size down if I can get my numbers to work. Depends on a lot of things....
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Old 03-10-2017, 10:19 AM
fuzzalow fuzzalow is offline
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My answers may not be useful to you because they reflect an approach to fit & position (i.e. balance/no core) that may differ from yours.

Quote:
Originally Posted by stephenmarklay View Post
I am contemplating buying a bike that is a 55cm top tube and my question is how much is too much for weight over the front. Looking at bar/stem combos
Going to a 55cm toptube bike won't make any difference in the weight provided you can balance your weight properly between the wheelbase axles by roughly centering your reach dimension with any combination of saddle setback and stem reach & drop.

Do not use the bars & headset as a weight bearing fixture on a bike - the front end is for steering. The proper fit & position balance places little weight into the hands with nice light touch onto the bars.

Quote:
I could replicate my “ideal” torso position with a the nitto pearl 120 (127) and the Compass Maes Parallel Handlebar. This is shallow drop also which is nice since the headtube is a wee but shorter 0.5-1.0cm less than normal.
Your ideal torso position is "ideal" only insofar as the torso is an influence to the angle with which your pelvis is situated and perched on the saddle. You set the pelvis angle first and then seek to locate a desired placement of the reach and drop of the bars doesn't corrupt & alter that pelvis angle. You then find an actual combination of stem & bar with the correct reach and bar drop that allows your hands to fall naturally and easily into the drops. Tilt forwards from the pelvis, arms hang down naturally and the hands fall onto the bars. No core used or needed, weight transferred from the hip into the pedals. Easy and effortless.

Always set the bike up with the drops; never with the tops or the hoods. If you cannot ride the drops easily and fluidly then you have not yet setup the bike correctly.

Good luck.
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Old 03-10-2017, 10:34 AM
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Hindmost Hindmost is online now
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Need to look at saddle set-back. Ideally with the smaller frame you can move the saddle back (a cm?) to achieve the preferred set-back.

Then with the right stem (a cm longer?) and the height raised to achieve the preferred reach and drop. Quill stems allow a lot of fit adjustability.

btw: I bought my first "real bike" in the same year and from the same source as your target bike.
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Old 03-10-2017, 10:35 AM
nate2351 nate2351 is offline
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Also if the bike has a steeper seat tube angle than your 57 you might find the distance from saddle to bars is exactly the same.
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Old 03-10-2017, 10:52 AM
stephenmarklay stephenmarklay is online now
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Thanks guys for the useful tips. I am a slow learner. 20 years ago I just rode what I had. Later I rode what looked right and over the last several I am starting to understand what is actually “right” for me.

On setback, that is relatively fixed for me and I can easily dial that in. This bike has short cranks so that puts me back a tad which I did not think about. That is a half centimeter that helps.

Fuzzalow. Great advice and I am basically already using this but I do think I could hone my current position a tad. I am pretty flexible and a longer flatter position works best for me to keep my low back happy.

You guys are awesome.
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Old 03-10-2017, 11:16 AM
fuzzalow fuzzalow is offline
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Quote:
Originally Posted by stephenmarklay View Post
Fuzzalow. Great advice and I am basically already using this but I do think I could hone my current position a tad. I am pretty flexible and a longer flatter position works best for me to keep my low back happy.
stephenmarklay-pal you sound like you're doin' OK. Great to hear.

I'll only kvetch just a little on your use, and implied reliance on, of "flexibility" in riding a dropbar sporting bicycle. Please fellas, don't use flexibility in riding a racebike. There is no place in cycling that should make you enjoy a sport at the stress and possible expense of your spinal discs in riding a bike.

A drop bar sporting bicycle is properly ridden with a fit & position the aligns the skeletal and muscular structures to propel it. There is little in a flexibility requirement in doing so. Please do not ride in a manner that stresses and eventually destroys your spinal discs by adopting a forced posture to a racer position which, doubly damning, also induces an incorrect pedal stroke by interfering with the firing sequence of the stroke.

All done in service of the ride.
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Old 03-10-2017, 12:50 PM
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Quote:
Originally Posted by stephenmarklay View Post
For reference I am about 5’11.75” and shrinking.

I normally ride a comfortably a 57cm. I have ridden frames as small as 56 and as large as 58cm. I mostly look at the top tube and headtube for level top tube bikes.
I have find that about a 127mm (nitto pearl) stem on a 57cm is right and now I am running a nitto noodle. That combo is a tad long for.

I am contemplating buying a bike that is a 55cm top tube and my question is how much is too much for weight over the front. Looking at bar/stem combos

I could replicate my “ideal” torso position with a the nitto pearl 120 (127) and the Compass Maes Parallel Handlebar. This is shallow drop also which is nice since the headtube is a wee but shorter 0.5-1.0cm less than normal.


I have seen lots of folks my size say they ride a 55cm and when I look at those old Lemond charts it puts me on a 55.5cm

Thanks so much.
I'm right there with you (.75" shorter) and I feel great on a 55. I've ridden 54-56 comfortably, and 55 is my sweet spot.

Curious what you inseam is?

I am relatively long torso with 31" inseam, which is why 55 works so well. I'm guessing yours is an inch or two more. 56 has me reaching a bit with any stem over 120mm, where 54 has me feeling too scrunched, for the most part.

I also like the feel of my saddle back a bit and my arms stretched a bit.
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Old 03-10-2017, 04:10 PM
giordana93 giordana93 is offline
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with all due respect to the Fuzz, I will say that hamstring flexibility plays a role in getting lower. i.e. it isn't flexibility in the back one needs, but rather in the hamstrings (not wanting to start a discussion, just a kvetch for a kvetch)

that said, as noted here and elsewhere, weight on the front end is directly tied to saddle set back, and you might run into a little variance in the seat tube angle that will affect reach

finally where your hands finally fall can vary between a shorter, deeper reach and a taller but longer one, so it might be trial and error, as in you can calculate it down to a millimeter on paper, but a road test will be where things get sorted out
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Old 03-10-2017, 06:35 PM
fuzzalow fuzzalow is offline
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Quote:
Originally Posted by giordana93 View Post
with all due respect to the Fuzz, I will say that hamstring flexibility plays a role in getting lower. i.e. it isn't flexibility in the back one needs, but rather in the hamstrings (not wanting to start a discussion, just a kvetch for a kvetch)
OK and with equal respect I'll simply accept you at your word about this. I'd like to see an example someday as to what this limitation does and its effect. In fact, I'd like to see the entire position on the bike to see if indeed the hamstring is the limitation or if that "tight hamstring" is the accepted blame for the limitation.

This is the side view:

Yes the hamstring must allow the pelvis to pivot further forwards and still complete a range of motion for a pedal stroke. But the hamstring is tiny in relation to all of the other muscles used in cycling. And yet this muscle is the one often given as making riding a racebike impossible.

Surely such a pronounced limitation must impact movements in living a normal life - like bending over to pick up a dropped pen. I am not disputing you, I am trying to make sense of this as, for me, the biomechanics don't add up. No reply necessary, I felt compelled to rebut because this oft-given excuse is way outta left field for me.
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Old 03-10-2017, 09:16 PM
stephenmarklay stephenmarklay is online now
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Quote:
Originally Posted by fuzzalow View Post
stephenmarklay-pal you sound like you're doin' OK. Great to hear.

I'll only kvetch just a little on your use, and implied reliance on, of "flexibility" in riding a dropbar sporting bicycle. Please fellas, don't use flexibility in riding a racebike. There is no place in cycling that should make you enjoy a sport at the stress and possible expense of your spinal discs in riding a bike.

A drop bar sporting bicycle is properly ridden with a fit & position the aligns the skeletal and muscular structures to propel it. There is little in a flexibility requirement in doing so. Please do not ride in a manner that stresses and eventually destroys your spinal discs by adopting a forced posture to a racer position which, doubly damning, also induces an incorrect pedal stroke by interfering with the firing sequence of the stroke.

All done in service of the ride.
I think dumbing down my use of flexy through you off. What I mean is that I have good range of motion in my hips to better realize a hip hinge motion. This keeps my back flat and does not put pressure on the discs as would rounder position. Having a longer cockpit allows me to keep my back flat rather than a smaller cockpit making me too cramped and rounding.
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Old 03-10-2017, 09:32 PM
fuzzalow fuzzalow is offline
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Quote:
Originally Posted by stephenmarklay View Post
I think dumbing down my use of flexy through you off. What I mean is that I have good range of motion in my hips to better realize a hip hinge motion. This keeps my back flat and does not put pressure on the discs as would rounder position. Having a longer cockpit allows me to keep my back flat rather than a smaller cockpit making me too cramped and rounding.
No worries, I would admit/confess that I took the opportunity to expanded on the discussion springboarding off the word "flexibility".

You sound like you're in a good place and that you know what what you're doin' so the tangent on flexibility was not directed at you. But I'm always aware that there are readers enjoying the conversation without posting so we ought to try to make it broader and interesting to readers even if in so doing we take liberties within our own conversation.
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Old 03-10-2017, 09:38 PM
stephenmarklay stephenmarklay is online now
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Quote:
Originally Posted by fuzzalow View Post
No worries, I would admit/confess that I took the opportunity to expanded on the discussion springboarding off the word "flexibility".

You sound like you're in a good place and that you know what what you're doin' so the tangent on flexibility was not directed at you. But I'm always aware that there are readers enjoying the conversation without posting so we ought to try to make it broader and interesting to readers even if in so doing we take liberties within our own conversation.
Fair enough. I have to say I do have some reservations when it comes to trying to increase hamstring flexibility. It does not in general hold true that increasing hamstring flexibility improves pain nor performance parameters.
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Old 03-13-2017, 11:06 PM
giordana93 giordana93 is offline
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just for the fun of discussion, I'll continue the drift about the hammies and concede a few things that I agree with you guys on. True, one does not need extreme flex in the hamstrings to ride a race bike in a normal (easily get and stay in the drops) position, especially if saddle height is reasonable, that is, not too high. On the other hand, let's engage in some "thought experiments" for the sake of discussion.
Fuzz had a great thread about one of my favorite riders, Fabian the Great. I know there are haters out there, but having ridden and followed cycling for nearly 40 years, I've seen quite a few guys pedal the bike, and he is one of those rare "poetry in motion" type of riders, in part owing to some of the factors Fuzz pointed out in that thread. Now, I'm sure Cancellara would have been great without being flexible, but I recall when A. Pruitt did his analysis/fit for Saxo, and here are some excerpts from that:
Quote:
Olympic time trial champion Fabian Cancellara made a clear impression on Pruitt, with the American proclaiming after the medical assessment and initial bike fit that, "I have learned a lot about the reason for this guy's success in the last few minutes". The reason for his praise? Cancellara's considerable flexibility and strength, which enable him to comfortably hold an aerodynamic tuck during time trials. Of the Saxo Bank riders seen, Cancellara seemed to impress Pruitt most, biomechanically; in fact, he had some good news for the Swiss TT specialist after the examination.

As is always the case, the BG assessment started off with an examination of the rider off the bike. Cancellara was judged to have good shoulder strength, and was then asked to touch his toes; he did more than that, putting the palms of his hands flat on the ground and earning praise from the assessor. His leg length was found to be equal.

He was then asked to lie on his back, straighten his leg and raise it upwards towards the vertical; he was found to have 85 degrees of angle on the right leg, with three more on the left. Pruitt was clearly impressed with this, saying that it was "very flexible for a big guy", while bringing his knees to his chest revealed what was termed, "huge glute [gluteal] flexibility," namely a right leg reading of 130 degrees and a left leg of 135. His glute strength was judged by Pruitt to be 'bulletproof'.
OK, so that's really just anecdotal and does not connect the dots between flex and sitting properly on the bike, so let's explore what's at work. 1st, I gotta clear up that I'm making the mistake of singling out the hamstring when I'm really talking about all of the butt/posterior muscles in the upper leg that are stretched when we reach down to touch the floor or pick up that pen off the floor. Most of us will naturally bend at the knees to accomplish that task, and indeed anyone can put their palms flat on the floor by simply bending at the knee. But imagine that you can't bend at the knee because you are perched on a saddle. What happens then? (And of course rather than reaching for a pen, we are going for the drops). Well if you are extremely tight, you will be limited to either a higher bar (or inability to use the drops) OR you will have to drop the saddle a touch. In fact, if you watch some of the live race coverage going on now, check out how low many pros saddles are. Or at least I should say that they still are pretty far away from having a locked out knee, especially when they are cruising along on the brake hoods. That's so they have some reserve for when they effectively raise their saddle by rolling forward to get low and aero and make it look effortless (cue the tape of Cancellara, Lemond, Sagan, or any other fluid pedaler). And yes, I would argue that having good flexibility allows a rider to have his/her cake and eat it too: able to bend over and get aero when needed, with a saddle height that is not excessively low for general riding--and especially for a good seated climbing position, when your chest is up and the hip angle opens so instead of effectively raising your saddle you are lowering it--you're no longer reaching for that pen on the ground, just bending to wash your hands. Note too that some people scoot to the back of the saddle when climbing, which again is a way to maintain a constant leg extension (and recruit the glutes). dropping the heel does the same thing (at least with a traditional ball of foot cleat placement; less effective with a rearward or mid arch cleat)


ok, just reread the above and want to make clear what I mean by effectively raising the saddle. let's say at 80 cm your leg is at maximum extension before your hips start wobbling as you maintain a 45 degree hip angle. sit up more vertical and you could raise the saddle a touch; bend forward and you will exceed your max and wobble because the attachment of the muscles to your hip bones as shone on Fuzzalow's anatomy graphic is moved further away, thus what I call an effective raising of the saddle. ok it's late, better stop before I start rambling even more...
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