Bicycle Mechanics - Upgrading a Crank

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View Full Version : Upgrading a Crank


finsfree
04-07-11, 09:08 PM
Hello,

I would like to upgrade my crank, but how do I know what crank will fit my bike? I think bike "techy" name for crank is bottom bracket...just wanted to make sure we were on the same page.

This is what I have
Click Here (http://www.motobecane.com/alplus/spr.html)

Thanks,


nwbikeman
04-07-11, 09:15 PM
most Shimano road cranks but not the Dura Ace 7900 but 7800 is ok, 7900 has different offset and ring spacing.

finsfree
04-07-11, 09:23 PM
most Shimano road cranks but not the Dura Ace 7900 but 7800 is ok, 7900 has different offset and ring spacing.

So any Shimano Ultegra crank would be fine (meaning something up to date)?


greyghost_6
04-07-11, 10:23 PM
To clarify, the bottom bracket is the bearing assembly that attaches to the inside or outside of the frame (yours is outside, so external). And the the crankset is the crankarms/chainrings, so they are 2 different things, just in that link you gave they grouped them together since they work as one system. You should be able to keep your bottom bracket since they standardized much of the external bottom bracket systems, and should be able to fit a shimano to the bike. But you could take the bike down to your LBS to see if your bottom bracket would fit a shimano crank.

nwbikeman
04-07-11, 11:00 PM
Ultegra would be a nice upgrade as it is a stiffer crank. If you are converting to compact then get the FSA compact f/deraileur as well.

simonaway427
04-08-11, 05:01 AM
are you going from a triple to a double?

Chris_W
04-08-11, 05:49 AM
To clarify, the bottom bracket is the bearing assembly that attaches to the inside or outside of the frame (yours is outside, so external). And the the crankset is the crankarms/chainrings, so they are 2 different things, just in that link you gave they grouped them together since they work as one system. You should be able to keep your bottom bracket since they standardized much of the external bottom bracket systems, and should be able to fit a shimano to the bike. But you could take the bike down to your LBS to see if your bottom bracket would fit a shimano crank.

Why do people reply without knowing what they're talking about? Your bottom bracket is a GXP, and so won't accept any Shimano cranks. To stick with the current bottom bracket then the only road triple crank other than the Elita that you have is the Truvativ Rouleur, but they are not easy to get hold of and are not so different from the Elita. It would therefore be best to change the bottom bracket as well as the crank. Shimano 105 or Ultegra would be the standard choice - not too heavy, good chainrings, stiff enough cranks. FSA are normally a bit cheaper but not as good as Shimano cranks IMO.

finsfree
04-08-11, 05:42 PM
Why do people reply without knowing what they're talking about? Your bottom bracket is a GXP, and so won't accept any Shimano cranks. To stick with the current bottom bracket then the only road triple crank other than the Elita that you have is the Truvativ Rouleur, but they are not easy to get hold of and are not so different from the Elita. It would therefore be best to change the bottom bracket as well as the crank. Shimano 105 or Ultegra would be the standard choice - not too heavy, good chainrings, stiff enough cranks. FSA are normally a bit cheaper but not as good as Shimano cranks IMO.

Ok thanks. I think Ultegra is the way to go for me, which means I am going to have to change my bottom bracket.

You were helpful.

Any tip on where to get one for less money?

achoo
04-08-11, 06:21 PM
Ok thanks. I think Ultegra is the way to go for me, which means I am going to have to change my bottom bracket.

You were helpful.

Any tip on where to get one for less money?
http://www.ribblecycles.co.uk/sp/road-track-bike/Chainsets-Road-Shimano-Ultegra-Triple-6703-10-Spd-Chainset/SHIMCHAR509