Tomm Willians

Today I was riding my ‘73 Follis when I noticed an issue with the drive side pedal becoming stiff. When I got home I popped off the dust cap hoping to lube the bearings and found that many of them were gone? (To where?)
Anyway I attempted to slap on another set of pedals and found they didn’t fit the crank arm threads, close but not quite. The threads looked to be the same count but the shaft on the French pedals looked ever so slightly smaller causing the other pedals to start to thread (perhaps a full turn) and then get very tight.
Is there another cause for this or is there just a slight difference here ?

79pmooney

French pedals threads and English are different and not compatible. Think 27" wheels and 700c. Or just about anything else English and French 50 years ago. Bottom brackets. Freewheel threading. Headsets. Stems, Handlebars. Frame tubes. Seatposts.

Bill Kapaun

French pedals have 14mm x 1.25mm thread while the far more common and slightly larger English size is 9/16" x 20

3alarmer 

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...your life becomes much easier if at this point, rather than searching out new French threaded pedals, you just rethread your current cranks with standard English threads. It' takes maybe 15 minutes to pull the arms and run an English RH amd LH threaded tap through both sides, carefully maintaining your 90 degree angle to the crank arms. Then, the whole world of modern, MKS pedals is available for your use, at reasonable prices.

I think I have a set of French threaded pedals I took off a PX-10 recently when I was upgrading to a wider pedal that would not hurt my feet. They are probably similar to what was on your Follis. They're in OK shape, and you can have them if you want. PM me. But the best fix at this point in time is to go English. (Unless you are one of those "all original" people.)

3alarmer 

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...BTW, sometimes you see advice to just use the new pedals to rethread the holes, by jamming them in there and using some cutting fluid to screw them in. Sometimes this works, but when it does not (and you get the new pedals in crooked), it's a much bigger job to rebush the holes with a threaded insert installed correctly. So I would say don't do this.

dsbrantjr

+1 Forcing things into places they aren't intended to go rarely works out well. If you need to re-tap the hole, use a tap not pedal threads.

Tomm Willians

Looking around my bench I found another set of French pedals that came off a Dawes (huh?) anyway....... new pedals on, problem solved.

Geepig

A Dawes! Haven't seen one of those in thirty years...

sch

Threading in this case: 1.25m or 20TPI are essentially identical for threaded part lengths under 5/8". However 14M
pedal shafts are about 0.05" smaller than 9/16" pedal shafts, which means the Fr threaded pedals screw into 9/16
cranks but the laxity means a mile or so of riding will begin to tear up the crank threads on aluminum cranks.
Conversely putting a 9/16 pedal into a Fr threaded crank will begin to bind in 1-2 turns and then to shred the crank
threads at worst or cut deeper ones at best but require 10x the amount of torque if not more.

SurferRosa

Overhaul 'em!

Gresp15C

Don't do this: I once had a french crank and 9/16 pedals. So I ground a little notch into each pedal spindle and used it as a tap to open up the threads in the crank arms. Then tightened it up and rode it that way for years. Some oil, patience, worked like a charm. But that was when I was young and poor, and didn't have access to oddball replacement parts.

Lakerat

"French pedals.... is it my imagination?" Slipping away with you. Or was it your balls slipping away?

Tomm Willians

What the hell is that even supposed to mean ?

Lakerat

Tomm- It was a dumb reference to the Temptations song, but it's running away, not slipping away. You lost your balls nonetheless.