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Old Peugot to CX bike(5 posts)

Old Peugot to CX bikeM4 Lou
Feb 11, 2002 4:06 PM
I was wondering about converting an old Peugot to a Cyclocross bike, but I've heard that you can't use new bb's on old French bikes. What do I do, and suggestions?
How old is it?Straightblock
Feb 11, 2002 7:38 PM
I don't remember when they changed over to English standards, but French bikes used to have different threads for the bottom bracket, and stem and headset sizes were also different. Freewheel threads & hubs were different at one time, too, and maybe even pedal threads. I'm pretty sure Phil Wood still offers a French thread bottom bracket (they're not cheap!), but if you ever need to replace a stem you're probably screwed if it's French diameter. Check Sheldon Brown's site; he should have plenty of information on French standards.
It is quite possible to do this, it may just take...sprockets
Feb 12, 2002 11:24 AM
some poking around. Assuming that you are in possession of the bicyclette but you do not have a couple of different types of BB cups laying around, or a magnifier, take the thing down to a good bike shop that has people old enough to remember the French/Italian/English thread standard era.

You need to figure out what type of BB you have. There may be no trouble at all, or you may need to improvise. Older bikes, built during big chunks of the 60-70's , will most likely have a French BB.

Later bikes have been known to have both English and Swiss BB threading. This would be fortunate since English is the "standard" on most bikes these days, and Swiss threads can be cut to English with little trouble.

French threading, which if I remember correctly, has right hand threads on both sides, are not as easily can be managed but you will have to look around. Phil Wood still has a BB for French BBs and that may be the most durable solution. Modern cranks should pop right onto the Phil unit.

Good, old bike shops will sometimes have good French pieces laying about to use to put together a good old-style BB system, which is not a bad way to go as good ones are lighter than cassette systems, and their easy rebuildability is actually a plus for uses like cyclocross where you will get really dirty. Some good cranks will fit on the French spindles, and you are good to go.

If you really want a modern BB/crank set-up and you have French threads, and for some reason you don't want a Phil Wood BB, you may be able to cut the threads out to a reasonable impression of Italian threads, for which modern gear does exist. This would be a last choice, as there is no guarantee that it will work perfectly.
You're using the Peugot frame to save money - right?Spoke Wrench
Feb 12, 2002 2:42 PM
That's not the cheap way to do it. If you want to build a project bike inexpensively, you need to start with a frame that uses English threads and sizes.
find a older mavic or stronglight bb.secourir
Feb 12, 2002 4:48 PM
most of the later ones fit shimano cranks for tapered bb's. some early models fit campy tapers. the one i am referring to in particular has cups which the bb needs to be chamfered or grooved (most good lbs 's can do this). it also easy to adjust a little chainline problem.

they are also completely sealed and use cartridge bearings so crud and muck wont foul them.

there is a diagram of one in zinn's book. sorry i dont have a pic as reference but i wouldnt trade mine for the world. most lbs' s still have the tolls needed for mounting them. ask/look around as they are relatively cheap.