Seizedpost

Hello all,
I am restoring an old touring bike with a Stronglight crank and SR SP-250 pedals. The non drive side pedal came out normally. The drive side pedal was very hard to get out and when it was removed there were little flakes of metal and the crank threads looked freshly tapped. The pedal spindle on the non drive side says VIA 6ZC and the drive side spindle says VIA 6ZN. The non drive side also says L (left) and the drive side says R (right), so the pedals are definitely on the correct sides.

What's going on? Were Japan-made SR pedals available with French threads? If not, and if these are standard threaded, maybe someone did a better job tapping the non drive crank arm?
Thanks!

JohnDThompson 

I'm not aware that Sakae Ringyo ever made metric thread pedals, and the "L" and "R" markings also argue against it. Perhaps it is your Stronglight crank that is metric thread? Stronglight often marked the pedal thread spec on the back of the arms, either "9/16" x 20" for English or "1.25 x 14" for metric.

T-Mar

SR offered French threaded pedals and crankarms into at least the very early 1980s. If they are French , I would think that they would be stamped with an M14 somewhere on the axle, probably the end or one of the wrench flats. As suggested, also check the crankarms, which should have the pedal threading stamped in the area of the pedal holes.

If the pedals were not lubricated when they were installed, there is also the possibility of some galvanic interaction which can bond aluminum to steel (think stuck seat posts). It's possible that some bonding occurred and that you were ripping out threads.

Seizedpost

T-Mar, I believe you are correct. I cleaned up the threads and now it goes in normally.
The crankarms both say 9/16 x 20.

Slightly OT: The non drive side pedal felt crunchy, so I regreased it. The drive side feels really good. Should I bother?

jimmuller 

Also pedals and crank arms would typically be marked D or G if French instead of R or L.

Miele Man

I've had the odd time when one pedal was a bit harder to get in or remove than the other side was.
perhaps it's tolerances? For example, the pedal eye is slightly undersize and/or the pedal spindle is slightly oversize.

It also could be that in the past one pedal was loosened/removed whilst the other one wasn't.

Another cause could be that the one pedal was slightly cross-thread when installed.

I find that a lot of times i can clean up the threads by screwing the pedal in from the backside of the crankarm.

Glad you were able to get it out.

If it were me and one of my pedals was a bit rough I'd overhaul both of them.

Cheers

Hilander

A letter "M" standing for "metric" is supposed to be stamped into the stem of the pedal axle, if the pedals are French threaded. SR Sakae denotes left and right pedals with L and R stamping regardless of threading.
Hope that helps!

Ghrumpy

By the way, VIA stands for the Japanese Vehicle Inspection Association. You'll see that stamped on all sorts of things on cars and bikes.
Outline of VIA?JAPAN VEHICLE INSPECTION ASSOCIATION (VIA)