Classic & Vintage - 9/16 v. 14/125

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aaronelliotross
08-10-06, 03:26 PM
Hi all,

So I found a great classic French bike with TA and Mavic and Mafac parts. It's got a fixed gear but no lock ring. The guy I bought it from said the club he belonged to used to make them qualify with a fixed gear bike in a time trial, a climb and a road race.

The problem is that I put 9/16 pedals on what I now realize are 25 / 114 cranks - 3 pin TA Specialités Professionals. Stupid, I know. <me>whacks self in head again...</me>

I know could have gotten them "resized" by the local bike shop, but I'm worried I may have screwed them up. Is it too late to do now? should I just buy a new set of cranks?

Thanks in advance,

Aaron

John E
08-10-06, 03:36 PM
I hope they are 14 / 1.25 and not 25 / 114 :) .

Since 9/16" is .288mm larger than 14mm, you may be OK. Have the threads chased and examined at the shop before giving up on the crankset.
aaronelliotross
08-10-06, 03:46 PM
Heh. I hope so too!

Thanks for the advice.

Aaron

Grand Bois
08-10-06, 06:05 PM
I wouldn't have thought it was possible to even get a 9/16" pedal started in a 14mm hole. Are you sure it has French threads? Not all French cranks have French threads.

That crankset is still available new.

http://www.bikespecialties.com/parts.html

http://velo-orange.blogspot.com/
repechage
08-10-06, 06:24 PM
Many TA cranks have an alloy pressed in dust plate on the back side, to change pedal threading to 9/16 x 20 you will have to knock that out first if present, I have tapped out TA's to 9/16" before, only problem is you cannot go back. TA does still make pedals though, very nice but in the $100. price range.

If you are worried that you have mucked up the first thread(s) turn, tap them out from the back side.
CV-6
08-10-06, 06:25 PM
I wouldn't have thought it was possible to even get a 9/16" pedal started in a 14mm hole. Are you sure it has French threads? Not all French cranks have French threads.

That crankset is still available new.

http://www.bikespecialties.com/parts.html

http://velo-orange.blogspot.com/

It is indeed possible. I did it 30 years ago when I put some Pro Ace pedals on my LeJeune's Stronglight 93 crank. :eek: