Stem length on custom frame

Discuss light weight issues concerning road bikes & parts.
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pdlpsher1
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by pdlpsher1

MoPho wrote: Besides when making a U-turn or doing a trackstand, why is toe overlap an issue? :noidea:
.
I live in Colorado and I’ve made countless U turns this past spring. I had to reverse course because of either a storm is brewing ahead of me or I encountered strong crosswinds and needed to change course. I don’t do track stands. Also if I do a remote start I have to be very careful riding in a parking lot.

Storms here have hail which is my main concern. Getting wet is not a big deal.


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C36
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by C36

In terms of handling I understood that the hands should be at the vertical of the front axle (dixit an ex-track-motorbike technician who moved to the road bike-manufacturing world).

Extreme long stems has been pointed as the cause of some descending crashes (remember Schleck some time ago)


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by Weenie


MoPho
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by MoPho

steventran wrote:
Thu Jul 18, 2019 7:13 pm
Pedaling up tight switchbacks has been an issue for me. Going slow and getting your foot/wheel caught is not fun. This obviously won't be an issue for people who don't ride them.



.

Hmm, I guess the only switchbacks I've ever encountered that were tight enough to worry about toe overlap is when mountain biking. On a road bike I've never seen a paved road that tight and I live in a mountainous area with many switchbacks.

pdlpsher1 wrote:
Thu Jul 18, 2019 7:15 pm


I live in Colorado and I’ve made countless U turns this past spring. I had to reverse course because of either a storm is brewing ahead of me or I encountered strong crosswinds and needed to change course. I don’t do track stands. Also if I do a remote start I have to be very careful riding in a parking lot.

Storms here have hail which is my main concern. Getting wet is not a big deal.

Like I said U-turns, and it's not that hard to make a u-turn without hitting your tire. Nearly 30 years of riding small frames (albeit a bit over 10 years on current geometry bikes) and I've only managed to knick my shoe a handful of times. It may happen every now and then, but I have been wondering why some folks make an important issue of it, seems not too hard to avoid but maybe I am wrong. :noidea:
I ask becuase I currently have a small semi-custom frame and they fitted a fork offset to reduce toe-overlap and it seems to come at the cost of shortening the trail to the point of making the bike unstable at speed, been thinking of changing the fork to a different offset which would put the wheel closer to the frame.

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pdlpsher1
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by pdlpsher1

I raise the issue because one can overcome the issue by workarounds in the frame geometry design without a big penalty. Once the frame is built the solutions are more limited. Builders care because it’s a safety issue and also they are paid to look after the well-being of the rider/customer.


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steventran
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by steventran

One specific incident I remember because I nearly fell was while taking the inside of a right hand bend going up the Stelvio. There was traffic, so I stuck to the right of the road. To be fair, I don't find myself dealing with bends like that on all my rides, but riding through San Francisco where there are lots of cars and pedestrians makes toe overlap a risk, too.
MoPho wrote:
Thu Jul 18, 2019 8:30 pm
steventran wrote:
Thu Jul 18, 2019 7:13 pm
Pedaling up tight switchbacks has been an issue for me. Going slow and getting your foot/wheel caught is not fun. This obviously won't be an issue for people who don't ride them.



.

Hmm, I guess the only switchbacks I've ever encountered that were tight enough to worry about toe overlap is when mountain biking. On a road bike I've never seen a paved road that tight and I live in a mountainous area with many switchbacks.

RussellS
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by RussellS

steventran wrote:
Thu Jul 18, 2019 5:58 pm
Perhaps I should ask the question this way:
Would a 100mm stem look too small on a frame with a 550mm or 555mm effective top tube?
No. A 10cm stem will look perfect on a medium size bike. I consider a 55cm toptube to be medium sized. For someone about 5'6" tall. Give or take an inch or two. Yes I know pros who are 6' tall use 55cm toptube frames. But they are not normal. I am 5'11" tall and use bikes with 57cm toptubes. Give or take. All but one has a 12cm stem. Your 55cm toptube will look fine with 10 or 11cm stems. I have one bike, loaded touring, that has a 10cm stem. It looks fine too. If you looked at it for a few minutes you might eventually notice the stem is a bit short for the big bike. This frame has a 58.8cm top tube. I've had to adjust my fit with a shorter stem and a no setback post. Bike rides perfect. Good or bad, many years ago it was on super sale and I needed a new loaded touring frame to replace the way too small one I had.

MoPho
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by MoPho

steventran wrote:
Thu Jul 18, 2019 9:07 pm
One specific incident I remember because I nearly fell was while taking the inside of a right hand bend going up the Stelvio. There was traffic, so I stuck to the right of the road. To be fair, I don't find myself dealing with bends like that on all my rides, but riding through San Francisco where there are lots of cars and pedestrians makes toe overlap a risk, too.

I live in the Bay Area and have ridden in SF as well, plus I lived/biked in LA and Boston and never had an issue (maybe when riding a fixie?), perhaps because I am used to riding a small bike. I guess my point is it is something I would never have thought about when buying a road bike, so I am always surprised when people bring it up as a factor


.

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pdlpsher1
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by pdlpsher1

I don't know if your Moots was a full-custom bike, meaning one designed for you from the ground up. Toe-overlap is calculated by the CAD program and shown to the designer. I would be really surprised if any builder wouldn't discuss it with the customer especially for a small bike. When you buy a production bike the manufacturers don't publish the figures because it involves many factors, including but not limited to tire size and cleat position. But manufacturers do change the bike's geometry to minimze toe-overlap on the smaller sizes. It makes sense for most people this wouldn't be a consideration since they have no ways to compare toe-overlap between brand x and brand y. But for a custom build a decision needs to be made between the rider and the builder. I never said toe-overlap should be avoided at all costs. I only mentioned it because the OP is doing a custom build and there are ways to minimize it.

In some ways I wish I was a few inches taller. Designing a small bike around 700C wheels can be challenging!

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silvalis
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by silvalis

RussellS wrote:
Thu Jul 18, 2019 9:50 pm
I consider a 55cm toptube to be medium sized. For someone about 5'6" tall. Give or take an inch or two. Yes I know pros who are 6' tall use 55cm toptube frames. But they are not normal.
A 5'6" person on a 55cm ett frame is also not normal.
Chasse patate

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