jdm1005

We are "First Tandem" people, having purchased a used Trek T50 in very good shape, but with the pedals out of phase. Or sync. Or whatever the term is. Anyway, I would like to put the two sets of cranks into the same position. What do I need to do? What tools do I need to purchase? Thanks for your help!

headasunder

basic run down is to loosen eccentric bb, rotate bb to loosen chain take chain off one of the chainrings sync pedals then reverse process,

lichtgrau

Before you take the effort: Even when your good old Trek seems to be in a good shape, chains are items subject to wear and I would definitely check the wear condition of both chains in advance. If you don't have the appropriate chain gage or don't know how to measure the chain lengthening with a vernier caliper, ask a bike shop to help you with this task. Severely worn chains damage the chain wheels and the cassettes. In that case you probably have to replace those items as well.

jdm1005

Thank you for the info and the video. At least now I have an idea of how to proceed. I think my bottom bracket looks different from the one in the video, but I understand the concept. Thanks!

jdm1005

Thanks for the heads-up about the chains. They seem pretty good, but I will check them out to make sure. Good advice!

jccaclimber

You can easily measure chain stretch (wear really, not stretch, it's just called that) with a ruler if you don't feel like taking it to a shop. Tons of articles online and in the Mechanics section here on how to do that.

jdm1005

Thanks for the heads-up!