Can someone tell me if the cranks on a Trek 400 have 9/16 threaded petal holes . I am thinking about buy this bike but wish to replace the petals with a petal that has SPD cleats. I understand that there currently are two "sizes" of petal threads 1/2 and 9/16. But I don't know what the standard size was when this bike was marketed. Mid 80's I think.

Thanks

They are 9/16"-sized pedal threads. That's pretty much the standard on road bikes. Half-inch pedals will be on one-piece cranksets and some BMX bikes.

Neal

If they are stock cranks, they'll be 9/16". 1/2" were predominantly on the American 1 piece cranks, and there was at least one odd sized French pedal threading. So, unless someone did something funny to the cranks, they're 9/16".

EDIT: Beat to the punch.

Did old cheaper road bikes with the forged one piece cranks use 1/2 I wonder, like the schwinn varsity? Not that I'll ever likely come across such a bike set up here in Canada, although CCM did produce its first 10speed road bikes in the '60s with one piece cranks, but I've yet to come across one.

I'd leave the petals on the plants.

What these guys said. Unless you have a French crankset (almost 0% chance of that), 9/16 is the size.

Yes, all Schwinn one piece cranks I have seen are 1/2" whether balloon, middle weight or "light weight" bikes.

I could use some petals right about now, given this faux "spring" we're having in New England.

Neal

Not to worry. We had a faux winter. I road all year here in Bahstan and only xc skied one day in the local woods. Horid xc ski year. Roads are dry today and its in the 40s. That's good enough!!!