Upgrading from 8 to 9 speed.

[iAmiAdam]

Due to youth racing gear restrictions etc. I need to change the rear cassette from a 12T to 14T, I've found a new cassette here; http://www.chainreactioncycles.com/Models.aspx?ModelID=387

How easy would it be to either upgrade the bike from 8 to 9 speed or take a cog off of the cassette?

Thanks, Adam

 

[PatrickPending]

new shifters if sti too, new chain, rear mech might be ok - if you've got friction shifters then should be no problem

 

[raindog]

A decent LBS should be able to supply you with an 8 speed cassette with a 14 bottom end. If you're going to start racing best to have decent local shop, or pals in your club, where you can get good advice.

 

[iAmiAdam]

Thanks Patrick.

Thanks Raindog too, I'll probably do that tbh, seems cheapest way.

 

[montage]

If you don't want to spend the extra cash, just adjust the rear derailleur so that it won't shift down to the 12, the race organisers should be happy enough with that

 

[iAmiAdam]

This will be the option until I get the money, having all 8 speed would be preferable when I have the money.

 

[mickle]

Don't bother upgrading to nine unless you have cash to burn. The biggest outlay (if you use Ergo or STIs) will be the shifters. Check out the prices for entry-level nine speed shifters before you go any further.

Then it starts to get complicated. A nine speed cassette will fit straight on to an eight speed freehub body (and vice versa). However they have different sprocket spacing and the sprockets are different thicknesses. A nine speed chain will run on an eight speed cassette but not the other way round so you'll need a new chain too. Your rear derailer geometry will be OK for eight or nine though the jockey wheels should be replaced for narrower nine speed ones to retain shifting precision at the back.

That was the easy bit.

Nine speed chains don't run well on many eight speed chain-rings and the spacing between them will be wrong too. There's nothing to be done about this but replace the chain-set itself. The front mech will be unhappy with the new set up too - over-shifting one way or the other. The only fix for this aside replacement is manually bending the cage plate to narrow it.

Don't bother.

 

[iAmiAdam]

I didn't think I was going to, now I'm definitely not.

I'll just have to find an 8 speed cassette and just have to use the dérailleur to lock off the gears for a temporary fix.