Cycling UK Forum

Hi everyone, I have recently bought an almost new Dawes Audax frame set, built up with new bits all round, including a tiara group set. It runs with a cassette with 25T but want to change to a 30. The mech is a sort cage, so can't cope with a 30 or even 28, so need a medium/long cage. The only Tiagra mechs I can find are 10 speed, does that mean 9 speed don't exist and the 10 speed work on 9 speed cassettes, too?

Thanks

Martin

10 speed tiagra mech will work fine (same shift ratio as 9 speed)
shimano don't list spec's for their latest 4601gs model, but it seems it will cope with 32t max (double) or 30t max (triple)
have you tried your existing mech with a 30? shimano spec's are quite conservative.

If you get the latest sora it can run 32 on the cassette. I know this is a drop in group set level but I doubt that anyone can tell the difference without looking at them!

10 speed tiagra mech will work fine (same shift ratio as 9 speed)
shimano don't list spec's for their latest 4601gs model, but it seems it will cope with 32t max (double) or 30t max (triple)
have you tried your existing mech with a 30? shimano spec's are quite conservative.

What about the chain - I have to assume that a 9 speed chain is slightly 'thicker' than a 10 speed, which will have an impact on the mech? I have tried (or rather, the shop I am using) putting a larger cassette on and the current mech already touches the 28T on the back ...

Martin

malverncyclist wrote:

What about the chain -
Martin

I've had no trouble using a 9 speed chain, shifters and drivetrain with a 10 speed ultegra rear mech.
is the 'shop' you are using not able to advise? to be fair, if they're outwitted by a simple issue such as this, you may be better off going else where.

I trust them - all the owner said was "it may be a problem, but if it IS I'll keep the new derailleur and give you the money as I'm using these on other bikes" - so no risk for me.

A 9 speed deore MTB mech will work fine (I ran one with my 9 speed tiagra set up for a while) and then you can have a cassette as big as you want.

If the 9 speed chain does rub on the 10 speed mech cage, just fit crinkle washers each side of the pulley wheels to space out the cage
http://www.gwr-fasteners.co.uk/crinkle- ... -525-c.asp
They are much thinner than regular washers (but thick enough for the job) and will ensure the screws won't come loose again, as a bonus.