upgrade option for 8 speed crank

Diarmuid

I want to do a cheap upgrade to a bike for my gf. She has a Trek 1000 with the stock 8 speed drivetrain. It's a Bontrager crank but presumably it's just a standard 8 speed crank and compatible with the Shimano gear. The problem is that it's a 50/39 which is a big tough for her. So I would like to switch out the crank for a 50/36 or even 50/34 if such a thing exists.

Any ideas / pointers?

EDIT: Needless to say it's a square taper.

cdaly_

What's in the cassette? Changing that out for a wider range is likely to be a cheaper option (if the rear derailleur has the reach for the longer chain).

Diarmuid

I couldn't find a cassette with a substantially (or any) easier gear, which currently is a 26T

lescol

One of these would look like your best option:- http://www.wiggle.co.uk/p/cycle/7/FSA_Vero_Compact_Chainset/5360036210/

http://www.sjscycles.co.uk/product-Unbranded-Alloy-Compact-Double-34-50-170-mm-Steel-Rings-Chainset-13441.htm

xz

I have a 50/36, with bb 8 speed that came off a Giant scr4, make me an offer, and I'll even throw in the cassette. Its a Truvative touro square taper with 170mm crank arm

gman2k

going compact may cause gip with your front derailleur

Diarmuid

xz wrote: »

I have a 50/36, with bb 8 speed that came off a Giant scr4, make me an offer, and I'll even throw in the cassette. Its a Truvative touro square taper with 170mm crank arm

umm give me a ball park to start with

cdaly_

Diarmuid wrote: »

I couldn't find a cassette with a substantially (or any) easier gear, which currently is a 26T

You need to be looking at MTB cassettes rather than road ones. You'll get 11-28t, 11-30t, 11-32t and 11-34t http://www.chainreactioncycles.com/Categories.aspx?CategoryID=572.

If you stay with your 26t cassette:
a 36t chainring will get you the same low gear as your 39t with a 28t cassette.
a 34t chainring will get you the same low gear as your 39t with a 30t cassette.

xz

start the haggling at €45

Diarmuid

cdaly_ wrote: »

You need to be looking at MTB cassettes rather than road ones.

Good call. I think that's my solution.

Sorry xz (for the moment)

xz

Diarmuid wrote: »

Good call. I think that's my solution.

Sorry xz (for the moment)

the cassette is a 12-26 the crank is perfect for what you need, and its powerspline, not squre taper, even if you took the crank and combine it with a MTB cassette, it would be better than what she has, throw in a wild offer...;)

Diarmuid

Back looking for a compact again.xz your offer still there?

xz

Yeah, for sure, I have the crank, rear mech a cassette and shifters if your interested

Diarmuid

Totally missed this reply! I'm interested in the crank, will it work in a square taper bb? What cassette do you have?

xz

I have the BB that goes with the cranks too, I forgot to mention it in my last post it is this one http://www.chainreactioncycles.com/SearchResults.aspx?Search=powerspline, it's still in good condition, but as you see, a replacement is fairly inexpensive. The cassette is a 12-26, the chainrings are 50/36 with 170mm cranks, I even have spare 8speed sti shifters if youre interested in those too.Hopefully the BB should just swap out for the old one, its 68x108mm btw. I will try and get some pics of everything up by the weekend