Correct crank / chainset on my mtb ???

CATCHDE

Hi , I Wonder if you guys can assist ?
I have a 2003 Specalized Hardrock with a 22,32,42 crankset on as standard,
Doing more & more road riding these days I would like to change to a 28,38,48 crankset for a bit more speed on the road, But I'm finding the crank I have bought when fitted the inner chainring touches the chainstay.... the only way to fit it is too remove the inner ring and just use it as a double, this is ok but the chain alignment could be better when on the lower gears on the rear cassette.
This is the 2nd chainset I have tried and the same result, Is there any cranksets with a 48t top sprocket that will fit my Spesh properly ?

Hope you can help
Dean

Marjory Stewart BAxtor

if you're doing lighter riding, there'll prolly be some road rings oot there, dunno if they fit with mtb cranks though

supersonic

Sounds like you need a longer bottom brackert axle.

Also a 48t compatible front mech would be an idea.

What cassette are you running?

CATCHDE

Thanks for that, Ive just been told the same thing from the guy in halfords,

Using a 7 speed cassette, smallest gear is 11t

Will my existing front mech not work ? i realise the curve of the mech frame will not be the same as the 48t chainwheel but hoped it would work.

supersonic

It will sorta work - you can use the 48T mechs on 42T rings, but not the other way round, or at least it is not recommended. Give it a try!

CATCHDE

Thanks Supersonic, think my bottom bracket axle length must be quite a short one, I see that anything from 110 to 122mm are easily available, I shall measure it tonight,
Also i can see that 68mm is the norm for shell diameter, but does the shell length differ ? or do all bikes have the same BB shell length ?

supersonic

They are either 68 or 73mm its easy to measure it, just measure straight accross the shell.

If you can, find what length bottom bracket axle the chainset manufacturerer recommends for a certain chainline.