Crankset Compatability - Dura Ace 7800

[The_Eggman]

Hi

My mate is currently running a 53-39 Dura Ace 7800 crankset on a Time VXR, and is keen to drop back to a compact, but the whole compatability thing is doing our heads in. We've had a good look at the BB and we still can't work out exactly what we need. Any easy way to tell what is going to bolt on? we're looking at lower end Shimano cranksets (105, Ultegra) or one of the FSA cranksets

Thanks in advance

[biker jk]

I would go for a 105 compact crank in silver to best match the rest of the groupset. You don't need to change the bottom bracket. Front derailleur will need to be lowered (if braze on make sure you can do this) and chain shortened by a few links. Here's a 105 compact crankset which would be compatible. Just make sure you choose the same crank length as the current 7800 crankset.

http://www.chainreactioncycles.com/Models.aspx?ModelID=50444

[__PG__]

All Shimano 'Hollowtech' cranksets will be compatible.

Re : cranklengths, Dura-Ace comes in a much wider range that 105/Ultegra. You may want to look at 7900 Dura Ace which is 'relatively' cheap these days as its just been superseded.

[scirocco]

Don't buy a low end/cheap FSA crank, you will regret it. I agree with 105 as a good choice; you can pick up a Shimano 105 Hollowtech compact crankset online for $150-$200 and the current 105 design will look like the 7800 DA that came with the bike. If you go for the current generation Ultegra and DA crankset they have a different look.

Shimano Hollowtech cranks are very, very straightforward to fit, especially if the bike is already fitted with them.

[The_Eggman]

Cheers guys

[__PG__]

You can always try for a 7800 Triple

[coffeeandwine]

This chart is VERY useful.