Road Racing & Aero Wheels

[Yellow Saddle]

Like I said, don't take it for gospel, If you tell me there is only 10mm there, then so be it.

But let me not guess anymore, it is not a mystery.

The OLD of a front wheel is 100mm.
The fork lowers are 40mm each, so in total the two eat into the available gap by 40mm, which leaves us 60mm.

Your tyre is 2.1 inches or 52mm. Which leaves 8mm.

The exact gap per size is 4mm. Waaaaay under my silly thumbsuck.

ta

Edit: I'm getting myself tangled in my own edits here. Sorry.

 

[oldroadman]

The irony of it all is that it is actually the other way around. Wheels are laterally compliant and vertically stiff.
With a modest amount of push on a wheel held like a steering wheel and pushed on the axle resting on a block of wood, you can easily make it bend 30mm. However, with a rider's weight on the bike, the wheel squashes in by less than 0.5mm (no tyre fitted). We all know that tyres are far more compliant than that Yet, bike magazine hacks claim they can "feel" the compliance in the wheel. And then paradoxically tell us that when they apply the power, the wheel doesn't argue and just shoots forward.

Product label science should best not be copied and repackaged as journalism.

Seems to me a lot of these journos are nowhere near generating enough power to bend a spoon, let alone wheels.

 

[oldroadman]

Like I said, don't take it for gospel, If you tell me there is only 10mm there, then so be it.

But let me not guess anymore, it is not a mystery.

The OLD of a front wheel is 100mm.
The fork lowers are 40mm each, so in total the two eat into the available gap by 40mm, which leaves us 60mm.

Your tyre is 2.1 inches or 52mm. Which leaves 8mm.

The exact gap per size is 4mm. Waaaaay under my silly thumbsuck.

ta

Edit: I'm getting myself tangled in my own edits here. Sorry.[/QU

Nothing wrong with 8mm under the fork crown - a lot of room!

 

[Justinslow]

30mm is just a thumbsuck based on a 24h Shimano 29" MTB wheel that rubbed the paint off the inside of his suspension fork. The customer couldn't explain the rub marks but upon investigation we discovered that the wheel easily flexed the (estimated) 30mm. What the customer found strange was that the wheel touched the one side only. But that's explained by the wheel's dish. It was a disc brake wheel. That's the worst case I've ever encountered but don't take the 30mm as gospel. I don't have a representative bike here to re-look at the distance.

More like the QR wasn't done up tight enough, under braking the wheel would slew over and possibly touch the fork, ask me how I know this...........

 

[oldroadman]

I'm trying to work out what a 29" MTB wheel has to do with road aero wheels? Maybe I misunderstood the clearance bit, because there are no 2.1" wide road tyres? If the forks are getting rubbed, then there's a serious problem, and as disc brakes are nor permitted in road racing, that would eliminate one cause, which just leaves the QR not tightened properly as a likely option. Never a good idea!

 

[jowwy]

I'm trying to work out what a 29" MTB wheel has to do with road aero wheels? Maybe I misunderstood the clearance bit, because there are no 2.1" wide road tyres? If the forks are getting rubbed, then there's a serious problem, and as disc brakes are nor permitted in road racing, that would eliminate one cause, which just leaves the QR not tightened properly as a likely option. Never a good idea!

because yellow saddle is trying to justify the nonsense he is spouting out........

 

[Yellow Saddle]

I'm trying to work out what a 29" MTB wheel has to do with road aero wheels? Maybe I misunderstood the clearance bit, because there are no 2.1" wide road tyres? If the forks are getting rubbed, then there's a serious problem, and as disc brakes are nor permitted in road racing, that would eliminate one cause, which just leaves the QR not tightened properly as a likely option. Never a good idea!

The discussion veered into wheel flexibility at some stage and I used an example of a flexible wheel I came across, which happened to be MTB wheel, to demonstrate a point.

 

[h0lly1991]

You lot are so funny.... From my warm seat reading this and looking from the outside it doesn't look like some people like being "outed" as a google bunny.
Anyway carry on its become my afternoon reading catching up with this thread.

 

[Spoked Wheels]

You lot are so funny.... From my warm seat reading this and looking from the outside it doesn't look like some people like being "outed" as a google bunny.
Anyway carry on its become my afternoon reading catching up with this thread.

Now, why did you have to post that? It ended the thread ...

I haven't done any reseach or study any case but I'm so suspicious of 29" MTB wheels when it comes to flexing.

Can anybody tell me I have no reason to be suspicious?