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So at what length does a rear mudguard become ineffective at protecting your back from sustaining a soaking?
If you were to look at a bike's profile and imagine the rear wheel as a clock face where would the hour hand be pointing to ensure adequate length? 2 'o' clock? 3 'o' clock? Any ideas?
Assume the mudguard is 1cm above the wheel for commuting purposes.
Please see technical drawing below to aid understanding of the question:
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Your stem is too long. 🙂
Presumably, you have a mudguard you plan to cut to length?
Why not cut a bit off at a time and ride through a few puddles and see? Would be interested to know...
Rachel (who constantly worries the same question with skirts)
Critical point would be the apex of the curve of the wheel i suspect - after that point angle of departure means it id getting chucked at your back
And if its in an effort to look cool - dont bother - a poop stain on your back is never cool , longer the better for me - big flap mods on the front are ace to help reduce feet soaking 🙂
Your pic needs more rainbows and teddy bears!
Going back to my maths I think the actual point depends on loads of factors like the amount of water held by the tyre, speed of travel (and hence angular velocity of tyre), height of your back above centre of wheel, distance from centre of wheel to your back etc etc.
BUT surely a commuter is generally about function over form, so unless you've got the worlds heaviest mudguard or it generates massive amounts of drag I'd just leave it long.
Just to be sure, I'd make mine go from 7:30 to 5. Just don't get a puncture...
2:37