Pro's.... think they're riding with toe overlap?

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sugarkane
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by sugarkane

7. Don't worry about it cause it's irrelevant

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Hexsense
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by Hexsense

TonyM wrote:
slowK wrote:I'm short (160cm), and toe overlap is an issue for me. I have about 2.5-3.5cm of overlap on my two road bikes (i.e. the front of my shoe is in line with the inner edge of the brake track in the worst scenario position of crank and wheel turning).
...
I should probably be on 165mm cranks too, but my bikes all came with 170mm cranks.
...

Yes you should use 165mm cranks.

Agreed, if you even care about pro's fitting then there are plenty of examples

165mm is the right size for people around 5'6-5'7 (167-170cm).
Pro_Names, Height/crank_length
Christ Froome, 185/172.5 = 1.07 (normal-short crank length to his height)
Bradley Wiggins, 190/177.5 = 1.07 (normal-short crank length to his height)
Peter Sagan, 184/172.5 = 1.07 (normal-short crank length to his height)
Adam Hansens, 185/180.0 = 1.02 (normal-long crank length to his height)

And here we are, 170cm rider with 165mm crank length get =1.03 pretty close to Adam Hansens that people says it's pretty long crank length to the height already.
160cm rider using 170mm crank length make it to whopping 0.94 ratio. it's like people around 185cm height using crank length=196mm, sound so wrong isn't it?

to get to normal-short ratio (1.07) then 170cm rider would use 158mm crank length.
And 160cm rider would use 149mm crank length...

ps. this is simplified estimation using just the height and crank length. Actual leg bone length will get to a much closer estimation, but the data are hard to find. This is just enough to make a point that slowK is using super long crank!

Gearhead65
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by Gearhead65

Pro don't have an overlap issue. They have their toes surgically shortened and go to a smaller shoe size.
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slowK
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by slowK

Yep - thanks for the replies. Shorter cranks will definitely be my next upgrade.

thedonnydino
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by thedonnydino

Another reason that pros don't care about overlap is because they ride big manufacturer frames that go to great lengths to reduce toe overlap. Some say it's because it's fear of litigation, others due to some obscure rule or law.

Cervelo used to run massive toe overlap and short wheel bases on their smaller frames, however subsequently responded to concern over overlap. All they did was slacken the head angle, and I believe change the rake a little bit. I even think they responded with a 650 wheel in smaller framsets initially. Ironically, Cervelo prided themselves in having similar, racey handling throughout their size range.

Having said that it is almost impossible to eliminate all overlap without reducing the size of the front wheel.

I have found that Italian frames run slacker head tube angles, which make them great for descending, but not particularly snappy bikes. On the other hand, if you look at the new Allez Sprint, it has much tighter head tube angles, and a short wheel base.

Nefarious86
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by Nefarious86

73.5 HTA on the Allez is particularty tight and is the same as a Tarmac and the FC is -3mm on a 58cm frame and -2mm on a 56cm.
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thedonnydino
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by thedonnydino

Nefarious86 wrote:73.5 HTA on the Allez is particularty tight and is the same as a Tarmac and the FC is -3mm on a 58cm frame and -2mm on a 56cm.


Toe overlap is almost a non issue on a 56 and 58.

On a 49 Allez Sprint, the FC is 564 and on a 52 it is 566.

On both a 49 and 52 Tarmac, the FC is 576 (they kept them consistent by slackening the HT angle quite a bit for the 49, and by having quite a long tt for the 52 relative to an Allez Sprint).

Fiery
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by Fiery

milesthedog wrote:Interesting on the stem length. I have heard pros report that they prefer stems over 120mm for stability, but interesting to see the consensus here that that's just not the case....

That's because stem length is the result, not the goal. Professional racers are skinny, especially in the upper body; they don't put as much weight over the front wheel as an average "big boned" amateur rider. Having a smaller frame tucks the front wheel closer in and puts more weight on it, while the stem ends up longer to provide the necessary reach. The also the effect of having a longer lever arm is also there, but it's not as important - this is why mattr was fine on his bike even with a shorter stem.
Last edited by Fiery on Wed May 17, 2017 10:28 pm, edited 1 time in total.

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Dr.Dos
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by Dr.Dos

Short stems also look shitty no matter the bike size. This includes everything <120mm.

wingguy
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by wingguy

thedonnydino wrote:On a 49 Allez Sprint, the FC is 564 and on a 52 it is 566.

On both a 49 and 52 Tarmac, the FC is 576 (they kept them consistent by slackening the HT angle quite a bit for the 49, and by having quite a long tt for the 52 relative to an Allez Sprint).

The 49 Tarmac is an outlier there as well. It's super long. The 49, 52 and 54 Tarmac all have the same reach measurement. The 49 is centimetres longer than some equivalents from other brands.

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C36
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by C36

Dr.Dos wrote:Short stems also look shitty no matter the bike size. This includes everything <120mm.

Well on a website looking (in theory) on optimisation that type of comment is irrelevant. We let the industry impose reduced frame sizes options (before cm by cm was the absolute norm) and we claim we are totally ok compensating with longer stems when we are patching a geometry flaw. We totally miss the impact on weight distribution or hand position reference to the front end geometry.


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Hexsense
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by Hexsense

wingguy wrote:The 49 Tarmac is an outlier there as well. It's super long. The 49, 52 and 54 Tarmac all have the same reach measurement. The 49 is centimetres longer than some equivalents from other brands.

I think i've read somewhere on small frame it's the compromise of slacker headtube angle or too long frame (thus short stem). Specialized engineer said short stem effect handling less than slacker head tube so they go that route with pretty long frame which require short stem.

Personally, i'm fine with even 70-71 head tube angle. It doesn't have to be 72-74.

Gavf
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by Gavf

The main problem for me with toe overlap is the mental scaring when waiting at lights with my left foot clipped in and the front end falls to the right, brushing against my 300 quid Sidi wire carbons :D

slowK
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by slowK

slowK wrote:Yep - thanks for the replies. Shorter cranks will definitely be my next upgrade.


Well, I went to my LBS yesterday to ask about this. They just took off some new 165mm cranks from another bike (the customer fitted a power meter). They offered a great price, so I'm getting them. Will be interesting to see if I notice a difference (not just toe overlap, but in other aspects too).

Hexsense
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by Hexsense

slowK wrote:
slowK wrote:Yep - thanks for the replies. Shorter cranks will definitely be my next upgrade.


Well, I went to my LBS yesterday to ask about this. They just took off some new 165mm cranks from another bike (the customer fitted a power meter). They offered a great price, so I'm getting them. Will be interesting to see if I notice a difference (not just toe overlap, but in other aspects too).

Transition to shorter crank (as i did go from 172.5 to 167.5 to 165 before)

-Saddle height should go up 3-5mm as your crank is now 5mm shorter.
-relearn the gear! you theoretically need lower gear at higher cadence. 170 down to 165 is only 3% difference though, one gear in the back is usually 6-12 percent different per gear. 52 vs 50 in the front is 4% difference.
Reason is: reduced torque of shorter crank make it feel like a harder gear. Pedaling circle is now smaller too (smaller circumference) if you move the foot at the same linear speed through smaller circumference, that'll naturally result in higher cadence without anymore effort. And if the crank was too long from the beginning, going down will not reduce your torque much as your leg's improved efficiency will offset it. So, it only improve things.
-it takes quite a few weeks to fully get used to it. Good luck and keep an eye on even shorter cranks!

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