Relation between wheelbase and BB-height for handling/cornering
#1
Wat.
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Relation between wheelbase and BB-height for handling/cornering
Does a shorter wheelbase allow for lower BB heights in terms of turning/cornering? My logic is that a shorter wheelbase (say 950mm vs 1050mm) allows for a smaller turning radius, and in theory shouldn't require as much steering input or, importantly, leaning into turns to accomplish the same turn that a longer wheelbase bike would require. Can anyone support or refute this idea?
Background: I got a custom 650c track bike made recently, but they built it around the measurements of a sort of wonky 650c fork (it's about 15mm longer axle-to-crown than all other 650c forks on the market). I've replaced the stock fork with an old 650c Litespeed fork since I wanted a brake drilling, but then noticed my BB drop to a height of around 272mm (from 280mm, which is what I requested and pretty standard for track bikes and velodrome use). This bike will be used for the street though and I'm a little worried how this lower BB will deal with pedal strike (preferably before trial and error). This bike also has a smaller wheelbase than all the 700c track bikes I've used, about 915mm instead of the 950-970mm of previous rides.
Anyways, any insight appreciated
Background: I got a custom 650c track bike made recently, but they built it around the measurements of a sort of wonky 650c fork (it's about 15mm longer axle-to-crown than all other 650c forks on the market). I've replaced the stock fork with an old 650c Litespeed fork since I wanted a brake drilling, but then noticed my BB drop to a height of around 272mm (from 280mm, which is what I requested and pretty standard for track bikes and velodrome use). This bike will be used for the street though and I'm a little worried how this lower BB will deal with pedal strike (preferably before trial and error). This bike also has a smaller wheelbase than all the 700c track bikes I've used, about 915mm instead of the 950-970mm of previous rides.
Anyways, any insight appreciated
#2
Senior Member
I don't think the wheelbase influences the turning radius a lot unless you do sharp turns at slow speeds; at normal speeds the front and rear wheel are generally in plane. 272 mm is not a low BB height I'd say.
FYI, by shortening the fork 15 mm you have increased the angles by ~1 degree, besides reducing the BB height.
FYI, by shortening the fork 15 mm you have increased the angles by ~1 degree, besides reducing the BB height.
#3
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the A-C change of the fork is likely to produce significant changes in the handling of the bike. The bb height is secondary. One of my friends had a bike that had a replacement fork on it, and it was so stable as to be un-steerable at low speed.
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Wheel base sure does have an effect on pedal strike, on a tandem compared to a single. But with just a couple of inches of difference (as opposed to a couple of feet) i don't think the rider will feel much difference due only to wheel base changes. Andy.