Shimano 105SC 7-Speed Crankset on 9 speed drivetrain

There are some vintage Shimano 105SC cranksets on e-Bay right now
attractive prices. I'm putting together a budget bike for my 16 year
old son (aka "Sam the Destroyer") and would like to use on IF it will
work with a 9 speed Shimano drivetrain. These are square-taper cranks
(should make no difference).

Does anyone know if they will work?

Thanks, Ken

"KD" kmorton.at.dsl-only.net@ wrote in message
...
| There are some vintage Shimano 105SC cranksets on e-Bay right now
| attractive prices. I'm putting together a budget bike for my 16 year
| old son (aka "Sam the Destroyer") and would like to use on IF it will
| work with a 9 speed Shimano drivetrain. These are square-taper cranks
| (should make no difference).
|
| Does anyone know if they will work?

I would think you'd have to swap the chainrings wit thinner ones to use
the proper chain with the 9sp cassette in the back. If they're 130BCD
and you have spare rings laying around, no reason it should not work.

KD Wrote:
There are some vintage Shimano 105SC cranksets on e-Bay right now
attractive prices. I'm putting together a budget bike for my 16 year
old son (aka "Sam the Destroyer") and would like to use on IF it will
work with a 9 speed Shimano drivetrain. These are square-taper cranks
(should make no difference).

Does anyone know if they will work?

Thanks, Ken

It will work. I use older Dura-ace cranks (7410 "8-speed") in
9-speed drivetrain. The rings aren't ramped and pinned but it stil
works fine

--
Gonzo Bob

"John Rees" wrote in message ...
"KD" kmorton.at.dsl-only.net@ wrote in message
...
| There are some vintage Shimano 105SC cranksets on e-Bay right now
| attractive prices. I'm putting together a budget bike for my 16 year
| old son (aka "Sam the Destroyer") and would like to use on IF it will
| work with a 9 speed Shimano drivetrain. These are square-taper cranks
| (should make no difference).
|
| Does anyone know if they will work?

I would think you'd have to swap the chainrings wit thinner ones to use
the proper chain with the 9sp cassette in the back. If they're 130BCD
and you have spare rings laying around, no reason it should not work.

From what I have seen the major differences are that the 9 speed
versions have little metal bits (ramps and pins)on the side of the
large (and middle) chain rings to help the chain jump up to the larger
rings. The thickness of the chainrings isn't really different although
the spacing on the 9 speed may be a tiny bit closer. The difference
in spacing is not, as some have claimed, enough to cause the 9s chain
to get stuck between chainrings. Overall the 7s crank will work fine
with 9s but may not shift quite as smoothly. This probably has more to
do with refinements in the Shimano design than any differences between
7s and 9s.