How do I find a crankset that fits my tourer properly?

unixnerd

My six year old Edinburgh Country touring has a Suntour CR310 crankset with a square taper BB and lots of very worn teeth. Time for a new one. It's a triple.

The other year I tried to fit a low rent Suntour mtb crankset a friend had lying about and the inner ring hit the chainstay. On the CR310 I have 5-6mm clearance.

How do I buy a crankset that I know will fit properly? Is this the chainline value in mm?

I don't really want to change the BB as it seems OK, but if I need to that's fine. Want to fit something half decent but not too expensive. This used to be my main bike and did 100+ miles a week, but these days it only comes out for long distance summer runs or winter roads runs (to save my nice road bike from the weather).

topdude

You either need to measure the axle length of your BB and buy a chainset to suit that.
Or, buy any chainset you like and a new BB to suit it.
Or, buy a Hollowtech style chainset with the axle built in which uses outboard bearing cups.

unixnerd

Or, buy a Hollowtech style chainset with the axle built in which uses outboard bearing cups.

Am I right in thinking those come with spacers to adjust the chainline? How many mm adjustment do they allow?

Monty Dog

FWIW most bikes use the same standard chainline dimension - typically 45mm for road triple (middle chainring) so if you buy a matching chainset and BB there should be no need for spacers unless you have an unusual frame i.e. manipulated rear stays for bigger clearances.

Berk Bonebonce

Buy from a touring specialist like Spa Cycles.

Hoopdriver

Do you really need to change the crank? Is that shot as well or is it just the chainrings that are worn? If it is just the chainrings, buy new ones of those and your BB dilemma simply doesn't arise. Spa Cycles has quite a good selection of TA chainrings - very high quality and they come in any size you could want or imagine, for both Shimano and Campagnolo.

That could solve you problem right there.

unixnerd

Tried but they seem to be an odd spec, couldn't find the correct chainrings anywhere :-( I'll try Spa cycles. Thanks.

Hoopdriver

Just curious - what size/spec are they? A lot of tourers are 110/74, most in fact. Are you certain you've measured them correctly? It can be tricky with five-arm spiders.

unixnerd

Honestly can't remember, must go and remeasure them!

Just did a nice 35 miler on the old warhorse, forgotten what a great bike she is. 8 speed Shimano Sora and to be honest it shifts really reliably and smoothly. Roads were too wet to take the "nice" bike out so duty fell to the tourer. Slower than my Cannondale by a good bit but I can carry all the spare clothing I like (it was +2 or 3C today), food, etc. and enjoy a nice comfy steel frame soaking the bumps up :-)

Hoopdriver

Sounds like a nice bike - I love good old reliable tourers. They never let you down. I've got one with about 70,000 miles on it.

unixnerd

Exactly, although mine has about 1/10 that mileage. I always think the cycle to work bunch are on the wrong bikes. You seldom see any of them on tourers yet I can't think of anything more suitable.

Hoopdriver

And the old classic tourers are really beautiful bikes, too.