Isaac1

Just bought a dura-ace rd7800 ss as a replacement for my ultegra rd6600 gs. But I'm worried my setup exceeds the rd7800's max tooth capacity. Im running a 11-28 cassette and a 52/42/30 crankset. I was wondering if i could disassemble my ultegra rd6600 and get the cage and swap it on my dura ace rd7800 small cage.

Iride01 

Your only issue with it is the max largest sprocket. Your total capacity is fine. So changing the cage won't do anything. But give the RD a try as it is if you already have it. You might find it works. But be certain that it doesn't have any interference between the jockey wheel and your 28 cog. Otherwise you'll have a big expensive mess.

This is one of those situations where a wolf tooth or other hanger extender will help. So if you aren't confident that your jockey wheel and 28 cog will not try to become one with each other, then get one.

https://si.shimano.com/en/pdfs/si/5V...0E-000-ENG.pdf


edit...
oops! my bad. I didn't look down at the next line for the front chainwheel difference. You are off on that too. Even swapping cages you might need a different RD. Maybe swapping cages will help that some if they interchange. You can always try. The worst thing since you already have it is that it won't work and you'll still have to get another.

On other matters... it's curious how the forum software show's you with zero posts. I guess you didn't write and post your own op.

Welcome to BF

KCT1986

The RD-7800 uses a different attachment method for the cage than the RD-6600.

The 6600 uses the older style of attachment with a long screw from the exterior of the body to secure the cage's solid pivot axle. The 7800 uses a bolt from the inside of the cage plate to secure the cage's hollow axle.

The newer Ultegra RDs, 6700/6800 may work. A possible issue with these is the alignment of the spring's anchor point, and the resulting tension. The other point of concern is the outer cage stopper pin (the pin that limits the rearward rotation of the cage)

You need to review the EV documents on Shimano's site to see the differences and explore what other 'newer' RD are similar.

Isaac1

Hi, so i was thinking on removing my 30t chainring on my crankset so I'm left with a setup of 11-28 cassette and a 52/39 crankset ( correction on my post, it should be 52/39/30 instead of 52/42/30) by any chance, would the rd7800 fit on my bike?

Isaac1

asd

rccardr 

Yes.