9 spd compact chainset

[thelonghouse]

I have recently purchased a new road frame with the intention of swapping
over the parts from my previous frame. The old frame has a 9 spd triple 105
chainset. However, I have been thinking of putting a compact set of cranks
on the new frame.

Do not want the expense of changing STIs but happy to change front
derailleur and would therefore like to stick with 9 spd. (I understand that
the 105 STIs can be used for double as well a triple). However, may
eventually want to change to 10 spd and therefore do not wish to buy a
crankset that would then become redundant.

I have been looking at the FC-R700 but not sure if this will work with 9
spd. Have also looked at FC-R600. Have looked at other makes but not sure
if there is a spacing issue (or is this only a problem at the back?)

I currently have an octalink BB on the old frame. However, I suppose that
this would be too long even if I do find an octalink compact crankset.

I was therefore wondering if someone would be able to suggest a good compact
crank and BB (including what length to use) that will work well with a 9 spd
setup (willing to spend upto £150).

Thanks,

Gordon

 

[Pete Biggs]

thelonghouse wrote:
...........
> I was therefore wondering if someone would be able to suggest a good
> compact crank and BB (including what length to use) that will work
> well with a 9 spd setup (willing to spend upto £150).

You can use a 10-speed chainset (or an 8-speed one) - whatever make & model
you fancy. The chainrings will mesh with your chain, and they could be
spaced further apart /if necessary/ with thin washers like these:
www.sjscycles.co.uk/product-0-Chainring-spacers-alloy-for-middle-outer-pack-20-5888.htm

I did this with a Campag 10sp triple chainset with 9sp everything else. I
only needed the washers to prevent the chain clinking against an adjacent
ring sometimes - but apparently not everyone gets this problem, let alone
anything more serious.

Use whatever BB length the crank manufacturer recommends. There's no issue
regarding the speed there.

~PB