Triathlon - Mixing wheel sizes, 700c and 650

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chummdizzle
10-04-08, 01:15 AM
So I'm building my first tri/tt bike, and after talking to a few guys I know I found that some of them run 650 front wheels on their 700c bikes. What is the reasoning behind this? what are the advantages/disadvantages of doing this?

KyleKranz
10-04-08, 10:01 AM
You'll always be going down hill, so it should be faster.
bikinpolitico
10-05-08, 09:52 PM
On smaller bikes, you want the smaller wheel so you can build a proper frame geometry without causing bad toe overlap. The 650c allows for this.

As to mixing the wheels, this was done on TT bikes in the 90s on the theory of getting more aero by lowering your front. The problem was it didn't pan out in real wind tunnel tests and has been largely abandoned. If you want to make your bike a retro tribute to Miguel Indurain, go for it, but there is not a good reason I know of to still do this.

Dwayne1
10-06-08, 02:33 PM
On smaller bikes, you want the smaller wheel so you can build a proper frame geometry without causing bad toe overlap. The 650c allows for this.

As to mixing the wheels, this was done on TT bikes in the 90s on the theory of getting more aero by lowering your front. The problem was it didn't pan out in real wind tunnel tests and has been largely abandoned. If you want to make your bike a retro tribute to Miguel Indurain, go for it, but there is not a good reason I know of to still do this.


What he said, unless you want somethind different I would'nt bother