Bicycle Mechanics - Switch from Compact to standard crankset

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duffetta
09-21-10, 07:41 PM
I currently have a Truvativ Elita Cross GXP crankset with 38/46 teeth on my Fuji Cross Pro that I use for commuting (bike will never see a cyclocross course). I'm looking at swapping to an Ultegra 6600 53/39 teeth crankset. Is there anything that I need to deal with other than resetting the location of the front derailleur and making sure that the BB is compatible? I'd probably swap over to an Ultegra BB at the same time anyway. The rest of the drivetrain is Ultegra 6600 (both derailleurs, chain, cassette).

Thanks,

Mark

Al1943
09-21-10, 07:53 PM
You will probably need a longer chain. If the chain is too short it will not shift smoothly into the big chainring - big cog combination smoothly. And you don't want that shift to fail, damage could occur.
`Orum
09-21-10, 08:02 PM
If you are using indexed shifters for a compact, you'll need a new front shifter too.

Al1943
09-21-10, 08:08 PM
If you are using indexed shifters for a compact, you'll need a new front shifter too.

??
I don't think so.
Bezalel
09-21-10, 08:25 PM
You need to make sure that your FD is compatible with a 53t chainring. (I think all road FDs are but haven't verified it.)
wrk101
09-21-10, 09:11 PM
If you are using indexed shifters for a compact, you'll need a new front shifter too.

+1 Huh?

+1 Check chain length, probably need a longer one. Raise FD.
M_S
09-21-10, 10:04 PM
Actually you're not even switching from a compact to a standard. If your current crank has a 38t inner, it's 130BCD. You could get pretty much the same gearing as the Ultegra crank with just a swap of the outer ring. Either way though, just check the chain length. 5 teeth isn't a whole lot though. It might be fine.
JiveTurkey
09-21-10, 11:52 PM
If you are using indexed shifters for a compact, you'll need a new front shifter too.

In before operator jumps all over you.
JiveTurkey
09-21-10, 11:55 PM
Actually you're not even switching from a compact to a standard. If your current crank has a 38t inner, it's 130BCD.

It could be either. There are 110 BCD 38T rings.
fietsbob
09-22-10, 09:29 AM
Should be easy to tell .. That 130-38t will be looking like its as small as the bolt circle will allow..
but perhaps whole crank + BB was a good deal. [NB May be incompatible on existing BB].
or guy wants to have more Shimano parts ..