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  #1321  
Old 04-16-2019, 02:50 PM
Calnago Calnago is offline
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Originally Posted by David Kirk View Post

Now onto my current offering - the Onesto XL. It's a 61 by 58.5 cm.

Great read. Mind if I ask what the saddle height is on those bikes as shown? I feel like I could just hop on and ride off with virtually no changes. I’ve had custom bikes from that vintage, with steel dimensions pretty much identical to the thicknesses you describe back then. They really have gotten “beer can thin” almost these days. If I were on the market for a custom steel frame, you’d certainly be someone I talk to, and one of the reasons is the closeness in size of the bikes we ride. I just think that someone who builds and rides about the same size frames has a pretty good understanding of the nuances of a slight change here and there and how that translates into the feel on the road.
Anyway. Thanks again. Enjoying the thread.
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  #1322  
Old 04-16-2019, 03:37 PM
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David Kirk David Kirk is offline
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Originally Posted by Calnago View Post
Great read. Mind if I ask what the saddle height is on those bikes as shown? I feel like I could just hop on and ride off with virtually no changes. I’ve had custom bikes from that vintage, with steel dimensions pretty much identical to the thicknesses you describe back then. They really have gotten “beer can thin” almost these days. If I were on the market for a custom steel frame, you’d certainly be someone I talk to, and one of the reasons is the closeness in size of the bikes we ride. I just think that someone who builds and rides about the same size frames has a pretty good understanding of the nuances of a slight change here and there and how that translates into the feel on the road.
Anyway. Thanks again. Enjoying the thread.
My saddle height is 825 center if BB to top of saddle. What is yours?

dave
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  #1323  
Old 04-16-2019, 04:10 PM
mhespenheide mhespenheide is offline
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Greg Orivetz.

dave
"Oravetz", I think. He could have been a great classics rider, if his career had gone differently.
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  #1324  
Old 04-16-2019, 04:25 PM
Calnago Calnago is offline
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My saddle height is 825 center if BB to top of saddle. What is yours?



dave
804mm from BB center to a straight edge across the top of the saddle. Maybe a dip of 4mm in the middle but the straight edge allows for consistent measurement every time. Frames’ shown probably a little tall for me but not much. 585 top tube based off a 72.8 seat tube angle is about perfect for me, fitwise. 84mm drop from saddle top to top of bars, but unlike you I love the classic bars (Deda Zero 100 Shallow, which aren’t really that “shallow” at 135mm drop), but Campagnolo levers work just perfectly for me with this setup.
Anyway, thanks for the writeup. Still trying to process today’s steel tubing thickness of, what did you say... a little over 0.5mm. Gotta be pretty careful with that and where you lean it as I’m sure it wouldn’t take much to dent.
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  #1325  
Old 04-16-2019, 04:30 PM
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David Kirk David Kirk is offline
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Originally Posted by mhespenheide View Post
"Oravetz", I think. He could have been a great classics rider, if his career had gone differently.
Thank you....yes I spelled it wrong.

I'm friends with him on facebook and he seems like a very cool guy.


dave
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  #1326  
Old 04-16-2019, 04:36 PM
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David Kirk David Kirk is offline
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Originally Posted by Calnago View Post
804mm from BB center to a straight edge across the top of the saddle. Maybe a dip of 4mm in the middle but the straight edge allows for consistent measurement every time. Frames’ shown probably a little tall for me but not much. 585 top tube based off a 72.8 seat tube angle is about perfect for me, fitwise. 84mm drop from saddle top to top of bars, but unlike you I love the classic bars (Deda Zero 100 Shallow, which aren’t really that “shallow” at 135mm drop), but Campagnolo levers work just perfectly for me with this setup.
Anyway, thanks for the writeup. Still trying to process today’s steel tubing thickness of, what did you say... a little over 0.5mm. Gotta be pretty careful with that and where you lean it as I’m sure it wouldn’t take much to dent.
You would think that would be the case but the stuff is very hard and very hard to dent. Back in the old days of 531 and Nivachrome if you whacked your top tube with the handlebar it would dent very easily. Not so with 953 because it's so hard. In fact I've never thought of it until now but I have a few hundred bikes out there using 953 and I've never had a customer tell me that they dented a tube.

953 is bizarre to work with. It's so hard that it's only a bit softer than the hacksaw blades used to cut it and if one gets hamfisted with it you'll rip all the teeth off the blade in a hurry. Don't ask me how I know.

Very tough to work with but wonderful to ride....more than worth the effort.

dave
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  #1327  
Old 04-16-2019, 06:08 PM
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AngryScientist AngryScientist is offline
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Great insider story about the team car roof racks Dave. That's funny!
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  #1328  
Old 04-18-2019, 10:50 AM
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David Kirk David Kirk is offline
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Another shot of two bikes I built nearly thirty years apart.

dave

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  #1329  
Old 04-18-2019, 12:56 PM
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m_moses m_moses is offline
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Thanks for the excellent review, Dave. I’ve never read a bike comparison written by someone who is a frame builder and a rider not to mention the builder of each bike. While your comments about the ride are understandably subjective, your insights regarding the construction and materials are illuminating. I also like the way you photographed the bikes. Both bikes are similar, yet very different but certainly representative of the evolution of the craft. I think this should get a wider audience.


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  #1330  
Old 04-19-2019, 05:13 PM
OtayBW OtayBW is offline
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Originally Posted by David Kirk View Post
You would think that would be the case but the stuff is very hard and very hard to dent. Back in the old days of 531 and Nivachrome if you whacked your top tube with the handlebar it would dent very easily. Not so with 953 because it's so hard. In fact I've never thought of it until now but I have a few hundred bikes out there using 953 and I've never had a customer tell me that they dented a tube.

953 is bizarre to work with. It's so hard that it's only a bit softer than the hacksaw blades used to cut it and if one gets hamfisted with it you'll rip all the teeth off the blade in a hurry. Don't ask me how I know.

Very tough to work with but wonderful to ride....more than worth the effort.

dave
Yep - refretting a guitar with SS frets is supposed to be a real artful think. You really have to know what you're doing. But the result.....ah....
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  #1331  
Old 04-23-2019, 10:04 AM
NHAero NHAero is offline
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Dave, this is very interesting!
With the modern steel tubing available, would a frame of the same riding characteristics (stiffness, strength) be lighter in steel or titanium?
And is using the stainless steel an advantage, disadvantage, or no difference vs. the non-stainless alternative(s)?

I should add, I was part of the aluminum bike frame project at MIT in 1974 that eventually led to Klein Bicycles. My undergrad thesis bike: http://museum.mit.edu/nom150/entries/1128

Diameter/wall thickness ratio of 50:1 was a design constraint to avoid compressive buckling. It's clear that guideline is not longer operative. What governs these choices now?

And a separate related question - how does a modern steel fork compare with carbon in weight? And how does rim brake vs. disc brake alter that?

Thanks!!!

Last edited by NHAero; 04-23-2019 at 10:08 AM.
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  #1332  
Old 04-23-2019, 11:15 AM
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David Kirk David Kirk is offline
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Originally Posted by NHAero View Post
Dave, this is very interesting!
With the modern steel tubing available, would a frame of the same riding characteristics (stiffness, strength) be lighter in steel or titanium?
And is using the stainless steel an advantage, disadvantage, or no difference vs. the non-stainless alternative(s)?

I should add, I was part of the aluminum bike frame project at MIT in 1974 that eventually led to Klein Bicycles. My undergrad thesis bike: http://museum.mit.edu/nom150/entries/1128

Diameter/wall thickness ratio of 50:1 was a design constraint to avoid compressive buckling. It's clear that guideline is not longer operative. What governs these choices now?

And a separate related question - how does a modern steel fork compare with carbon in weight? And how does rim brake vs. disc brake alter that?

Thanks!!!
There's a lot of questions packed into a small space here....I'll do my best to answer them.

- "With the modern steel tubing available, would a frame of the same riding characteristics (stiffness, strength) be lighter in steel or titanium?" - I see where you are going and don't know that one can give a real-life practical answer to this. The issue is that the stiffness of Ti is about 30% less than steel so making a steel and Ti frame have the same ride is near impossible. It's pretty simple to give the front end of the bike a similar ride by the numbers (using increased diameter on the Ti tubes) but much less so in the rear. This is because the chainstay diameters are limited by the small space between the chainring and the tire. So unlike the main tubes one can't just throw diameter at the c-stays to make up for the lack of stiffness in the material. One can make the tube oval in cross section and it helps a little but not much as the main loads the c-stays see are lateral bending loads (with a slight amount of torsional and compression) and an oval tube isn't much stiffer laterally than a smaller round one.....so....in the end a round steel stay with good design will be stiffer than most any Ti stay.

This is a long way of saying that it's damn tough to make bikes out of these dissimilar materials ride the same. You can make them each ride well but it's hard to make them the same.

All that said Ti being lighter than steel usually means that it makes a lighter frame. Whether you like the ride is a personal thing. I'm tall (6'4") but not very heavy (about 180#) and I worked very hard back in the day to make a Ti bike I could love and never really got there. The frames always felt unbalanced in their flex with the front ends being fine but the rear wagging around too much. For this reason I've never owned a Ti bike that I loved.....and I owned more than a few. A small light rider can be very well served by Ti but IMHO larger riders are better served by steel bikes even if they weigh a few ounces more.



- "And is using the stainless steel an advantage, disadvantage, or no difference vs. the non-stainless alternative" - Aside for the corrosion protection that stainless brings I see no reason to prefer it as a material.....that said.....I use a lot of stainless. But not for the fact that it 'stains-less' but because the material is so damn strong that it can be made very thin and this in turn can give a wonderful ride and save weight at the same time. If non-stainless were strong enough to pull this off I'd no doubt use it but that not being the case I use a lot of stainless even on painted bikes.




- "Diameter/wall thickness ratio of 50:1 was a design constraint to avoid compressive buckling. It's clear that guideline is not longer operative. What governs these choices now?" - The limiting factor at this point in reducing tube wall thickness is not the end use but how thin the tube maker can can effectively make the tube. I use a lot of Reynolds 953 and the walls are .5/.35/.5 on the main tubes and the guys at Reynolds say that this is about as thin as they can go. The issue is one of tolerance - I'm told that they can hold a +/- 10% on the tube walls regardless of how thin they go. If it's old school 531 with a wall of .9/.7/.9 and you reduce it but 10% you're just fine.....but make that wall .35 and cut that by 10% and you're really getting down there.



- "And a separate related question - how does a modern steel fork compare with carbon in weight? And how does rim brake vs. disc brake alter that?" - I honestly don't have a solid answer to this. I don't often weigh my forks and I almost never weigh carbon forks....if I hold more than one a year in my hands that would surprise me. Any way you slice it the carbon fork will be lighter than my steel fork. Will the stiffness of that carbon fork (given it needs to work with the heaviest rider who might ever buy it - industry standard being 275# last I heard) work well for the rider? Will it be the proper rake to match the frame design to give the ideal amount of trail? Will it even be straight (all too many aren't even close)? That's always my question.

How much weight will need to be added to make the steel fork happy to have a disc brake? I don't know. I never weighed it. The larger issue is the stiffness of said fork. In other words will the stiffness we need to add to a disc fork to make it safe detract from the ride? In many cases the answer is yes. If you're a big rider and using wide tires (as many disc guys are doing) then the difference might not matter to you....but to a light rider the difference will be greater.




I hope that all makes sense. Time to get to the bench and ruin some tooling cutting stainless.

dave
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  #1333  
Old 04-23-2019, 11:42 AM
NHAero NHAero is offline
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Makes a lot of sense, and thank you.
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  #1334  
Old 04-23-2019, 07:46 PM
soulspinner soulspinner is offline
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Originally Posted by David Kirk View Post
I got to see that car once and it made me laugh out loud.

The roof rack was bolted THROUGH the roof with carriage bolts. They stood on the roof, drilled holes through the roof and bolted it on. It wasn't coming off that's for sure.

Someone no doubt got that thing for really cheap when they passed it on.

dave
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  #1335  
Old 04-23-2019, 08:49 PM
Clean39T Clean39T is offline
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Originally Posted by David Kirk View Post
Will the stiffness of that carbon fork (given it needs to work with the heaviest rider who might ever buy it - industry standard being 275# last I heard) work well for the rider?
@NHAero:

Even at 170 racing weight, currently 185 , this is a difference I can definitely feel on the road - and what I've found is that the standard stiffness of carbon forks is absolutely a compromise in terms of comfort and handling for performance-oriented, standard-tire (25-28mm) applications.

I've ridden Dave's fork on my MRB (along with Tom's fork on my Spectrum and Dave W's fork(s) on past Ellis') back to back with ENVE 1.0 and 2.0 forks, 3T Rigida LTD, Ouzo Pro, AlphaQ, and have memories of a Falz, plus at least half-a-dozen others - and I can say beyond a shadow of a doubt that an expertly-built custom steel fork feels better than anything else out there.

My Kirk fork and the fork that was on Dave Wages' personal Ellis are the two best I've ever ridden - the Kirk probably because it's custom to me and the Ellis probably because it was custom to that Dave, and we're roughly the same proportions. Supple and precise are the two words that come to mind. Functional beauty too.

The other two are/were a bit stiffer, by design I suspect, being as both were for heavier riders and in the Spectrum case, has to take a front load. I'd still take either of those over any carbon fork I've ridden.

I'd also take all four over any production steel fork I've ridden - the one on the CSI I had, the one on the NHX I had, the one on the Colnago Master, etc. - as each of those were stiffer and less compliant, for me at my weight anyway.

There's really only one use case where I'd want a carbon fork: if I get a custom Crumpton, Holland, or Parlee carbon rig just because I like the aesthetic of tube-to-tube construction, and in that case, I'd want to get a custom Mike Lopez fork if I could..

I'll add too that both Kirk007 and I found that the disc fork on Dave's former cross bike still rides great despite being beefed up for handling braking loads. Looks the business too

Anyway, that's my sales pitch for custom steel forks from a user's perspective.

Last edited by Clean39T; 04-24-2019 at 12:01 AM.
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