French pedal threading
 

i have an old pair of gipiemme sprint pedals, and although they are italian made i am coming to believe they might be french threaded. they are marked D and S, and i am assuming the d is right, s being left. The strange thing is that they both seem to be threaded in the same direction. The right pedal will thread into the right crank arm, the left pedal will not thread into the left. I have chamfered the threads and still nothing. I realize that a french pedal will often thread into an iso crank, but my question is are french pedals threaded the same both left and right (not anti clockwise for the left pedal)? i cant find this information anywhere on the net.

thanks in advance

megatron

D and S is Italian for right and left, leading to dexterity and sinister. Nobody likes a southpaw, apparently.

French pedal threads are slightly undersize compared to English threading, so strip out when mixed. L and R threaded as normal on the 3 sets I've owned.

You should be able to easily see whether they are opposite threaded.

Italian threads have a slightly different thread shape but should work. I'd guess that the thread tolerances are a little off in different directions for at least one of your pedals.