Help Plz

SpiderNdc Posts: 137
edited September 2010 in Workshop
Hi i have a old racing bike with 20 speed so 5 on back so my chain is 5 -7 sp. , and i would like to fit new crank set on front one of external b/b sora double , do you know if that set up will work and not rubbing against small and big ring
Thx Greg


  • keef66
    keef66 Posts: 13,123
    Do you mean 10 speed? You could only have 20 speed with 5 cogs at the back if you had 4 chainrings, which would be unusual if not unique.

    Or do you have 20 speed, (2 chainrings, 10 sprockets at the back)? In which case your 5-7 speed cahin would be too thick.
  • Really sorry 10 sp :P so 2 front 5 back Thx
  • keef66
    keef66 Posts: 13,123
    So you're just replacing the existing double crankset with another double. I'd have thought all you need is the crankset and BB then.

    You might have to move the front mech up / down a bit if the big chainring's a different size, and you'd be best to set up the cable tension / limit screws from scratch.
  • cool thx