lamap

Dear all


In a moment of weakness I bought an 1970's Peugeot road bike, that I am trying to get in good shape.

When striping the crankset, cotter type, I was not able to remove one of the cotter. My plan is to fit a square taper sealed BB and a new crank anyway.

Can you advise on the square taper axle lenght? Cotter axle is 140mm,

I guess the new axel should be shorter, and I see on ebay sizes from 103 to 131mm.

I dont have the new cranks yet, Should I buy the crank first, or is there some kind of measure I can choose?


Thank you for your help,


Kind regards


Luis

branko_76 

What is the width of the bottom bracket shell ?

3alarmer 

...look for the crank first. The new crank you choose will either specify the spindle length required, or if you buy an older used one, the spindle length will be specified somewhere, like on Velobase. You also need to determine if you have French threading in the BB shell, or if your bike is late enough in the 70's that it has standard threading. If it has a cottered crank now, the chances are pretty solid that it's French threading.

So you can't use just any old BB unit off ebay or Amazon. Look on Velo Orange for the French threaded unit they sell there if that's what you have.

Don't order anything until you have the old spindle out and the fixed cup removed. Sometimes this becomes problematic.

noobinsf 

The bottom bracket is more than likely French threaded, so you would have limited options for a sealed cartridge BB. Velo Orange makes a range of spindle lengths, and it will depend on your crankset, so yes, try to research cranksets and bottom brackets at the same time.

Another thing you could do is use the same bottom bracket cups with a new square taper spindle. There are a lot of resources about this type of transition -- search google for "cottered to cotterless conversion."

3alarmer 

....just for the record, old Peugeot cottered cups have a smaller opening than almost everything else. So this often becomes another frustrating exercise. There's a reason so many people hate older French bikes. Not me of course, but so many people.

verktyg 

Decide on the cranks 1st then you will know what BB you will need.

Figure on getting a complete BB with cups and spindle/axle. Just trying to use a cotterless spindle with the old cups probably will not work well because of the ball track locations - see chart below.

Also, the old cups used with low end cottered cranks were poor quality and are likely to be worn out. The new spindle may have smaller or larger diameter ends and not fit the old cups.


Note, some Peugeot bikes used Left Hand Thread Fixed Cups (drive side). Those were also known as Swiss Thread Metric. Getting a Swiss Thread Fixed Cup is going to be difficult.

branko_76 "What is the width of the bottom bracket shell ?"

Almost all Peugeot road bikes had 68mm wide BB shells.

verktyg

repechage

70's French... big percentage chance French threading.
Way back often a Sugino Maxi spindle was used... now I do not recall if we used one designed for a 68 mm shell or Italian 70 mm shell.

If there is a bike co-op around that is open... a cottered Peugeot of the 70's is a fun bike but budget sourcing is appropriate.

dedhed

Decide on the crank but don't buy until you know you can get the correct bottom bracket.

JohnDThompson 

As @noobinsf notes, the shell is probably French thread, although some late 70s/early 80s Peugeots may have Swiss thread (same as French, but with a left-hand thread fixed cup to resist precessional loosening). If French thread, Velo-Orange offers a French-thread cartridge that may work for you. If Swiss thread, they also offer an unthreaded cartridge. The limitation is whether there is a spindle length that will work with the crank you intend to use. If you're willing to spend the money, Phil Wood cartridges are available in a wide variety of spindle configurations and thread specs, including both French and Swiss. It is virtually certain that a Phil cartridge can be found to work with whatever crank you prefer, but they're not cheap. On the other hand, a Phil cartridge is likely to last as long as you own the bike, so you only have to buy it once.

lamap

How, what a great forum!

Thank you all for the usefull information.

The cups are out with the help of a vise, I guess they are french type (both like regular RH screws).

So I will begin looking for a square tapered crank. After I will then buy a sealed type as the ones from Velo Orange.

Kind regards,

Luis

randyjawa 

I just got a Peugeot Crank set, with Peugeot boldly pantographed into the crank arms. Yours for cheap and I can include the bottom bracket but it is not French threaded. Anyway, the crank in question just came off of this bike...


Sorry, I don't have a picture of the actual crank set but this is identical to the one that I do have