Compatability DA7900 ULT6600/6700..

[McQueen]

Have a new Serotta on order with Dura-Ace 7900.

I have my current 1990's era Serotta TG currently outfitted with Ultegra 9 speed - R600 cranks - 600 brakes, etc. Shifting has been a struggle, tried the Gore cables, but my shifters are beat - plastic parts missing, etc..

I now want to upgrade my old bike to 10 speed, so that my wheels/cassettes are interchangeable.

If I upgrade to Ultegra 6600 or 6700 (both 10 speed), I figure I'll need new STI levers, new front and rear derailleurs, chain, and I need a new set of brakes - brake pads are hard to get for my era calipers.

Question is this - how compatable is the dura-ace 7900 cassette with the ultegra (6600 or 6700) components?

Secondly, is there going to be any compatability issues with chainrings? (probably not a bad idea to get some new teeth, anyways)

Is it worth it for 6700 vs 6600?

[harryschwartzma]

Actually, all you need are brifters and a cassette and chain to be set.

[oldpotatoe]

Have a new Serotta on order with Dura-Ace 7900.

I have my current 1990's era Serotta TG currently outfitted with Ultegra 9 speed - R600 cranks - 600 brakes, etc. Shifting has been a struggle, tried the Gore cables, but my shifters are beat - plastic parts missing, etc..

I now want to upgrade my old bike to 10 speed, so that my wheels/cassettes are interchangeable.

If I upgrade to Ultegra 6600 or 6700 (both 10 speed), I figure I'll need new STI levers, new front and rear derailleurs, chain, and I need a new set of brakes - brake pads are hard to get for my era calipers.

Question is this - how compatable is the dura-ace 7900 cassette with the ultegra (6600 or 6700) components?

Secondly, is there going to be any compatability issues with chainrings? (probably not a bad idea to get some new teeth, anyways)

Is it worth it for 6700 vs 6600?

With 6700 levers you need a new front derailleur, but not rear if the old one isn't worn out. You 'may' need new brakes but I would try your old ones to see if the performance is acceptable or not.

a 7900 cogset and chain is completely intercompatible with any other shimano 10s systems, cluding 105(sram too) BUT a 6600 or 7800 or 5600 cogset and chain is too and is less expensive.

Samo with chainrings altho the 6700 and 7900 cranks/chainrings are stiffer and shift under load better.

'Worth' is a big word. 6600 is leaving the marketplace quickly. 6700 is a lot more expensive than 6600.

[Pete Serotta]

Wayne Stetina, who is responsible for R&D at Shimano American, and who has a long racing pedigree, had 7800 cassettes on all of his 7900 and Di2 test bikes the last 2 years with the 7900 chain, including when I rode his bike set up with Di2 in Boulder City during the 2008 Interbike. So, similarly, there is no compelling reason to upgrade to a 6700 cassette before your 6600 cassette wears out.
Stetina does warn that the 6750 crank and chainrings with your 6600 shifting system will require very precise front derailleur and cable tension adjustment to prevent chain rub in top gear because the throw of the shifter/front derailleur combination isn’t quite as far as the slightly wider 6700; it’s actually closer to old 9-speed front chainring spacing width. So the potential problem with that front combination is that, if the front derailleur isn’t perfectly aligned, either the front derailleur won’t want to stay all the way to the outer limit stop, or else it will be rubbing in the trim position in the big/big combination, or in the small/big combination. Wayne has found that it seems to help if the front derailleur is very slightly toed out, so it clears more easily in the large rear cog on both rings, yet still can be tight enough cable tension to hold the front derailleur all the way to the outer limit stop.
-Lennard
\

ALso I have used 6600 and 67oo casettes and have seen no difference in performance (but the that is me Mr. Slow)

[woolly]

Wow, I didn't realize that an Ultegra 6500 (9-speed) triple crank would work well with the 10-speed stuff.

So all I need are the new shifters, chain, & cassette to do the conversion. And a new front derailleur if I don't want the front shifting to be super-finicky to set up. Did I get that right?

[palincss]

I need a new set of brakes - brake pads are hard to get for my era calipers.


Sorry, I don't believe it. What's so special about your calipers that you won't find a replacement for here: http://www.koolstop.com/brakes/index.php ? I believe the "Dura Road Holder" will fit your brakes.

[nahtnoj]

It seems that perhaps your crank is from the 8 speed era? There is a current R600 crank that is 10 speed compact, but I think you are talking about something older. I don't think a 10 speed chain is going to be very happy on 8 speed rings.

[oldpotatoe]

Wow, I didn't realize that an Ultegra 6500 (9-speed) triple crank would work well with the 10-speed stuff.

So all I need are the new shifters, chain, & cassette to do the conversion. And a new front derailleur if I don't want the front shifting to be super-finicky to set up. Did I get that right?

6700 needs a 6700 front der. Not a 6600.
A 6600 front der won't work with 6700 shifters, not wide enough since there is no trim on 6700 front shifters. Not sure about triple.

[oldpotatoe]

It seems that perhaps your crank is from the 8 speed era? There is a current R600 crank that is 10 speed compact, but I think you are talking about something older. I don't think a 10 speed chain is going to be very happy on 8 speed rings.

Actually with a little shifting finesse, a 8s crank is just fine with a 10s shifter and chain. Just shift gently to the big ring and back. You won't get the chain stuck between rings nor will it skate. I use a C-Record crank from 1987 or so and a 10s chain, no problem.

[regularguy412]

I'm using an 8-speed era crank (7410 DA) with 10-speed Dura Ace double shifters. My only real concession besides the 10S chain and derailleurs , was swapping in a 10S 39-tooth inner chain ring. I've had zero shifting issues and I've put about 2,500 miles on this setup.

I just really like the 7410 crankset and have a practically new Phil 103 mm BB for it.

Mike in AR:beer:

[dave thompson]

6700 needs a 6700 front der. Not a 6600.
A 6600 front der won't work with 6700 shifters, not wide enough since there is no trim on 6700 front shifters. Not sure about triple.
No trim? I have trim on both the big and small rings on my 6700 front shifter. Works very well too.

[McQueen]

Thanks for all the responses..

Yes - my cranks and brakes are from the 8 speed era.

I had upgraded the shifters and rear derailleur to 9 speed..

The brakes - yeah guilty of not doing enough homework - got replacement ultegra pads some time back and they didnt work with the old style calipers - so kind of stopped looking - but it looks like kool stop has the ones I was looking for.

So it sounds like the best bet for me, may be to find a cheap 6600 setup, since I'll have more adjustability on the fron derailleur - I can start out with using my current front derailleur and for that matter, could try the rear, just with a new cassette and chain, and it would be the low cost option.

The 6700 - the benefits would be the hidden shifter cable (under the handle bar tape) and being the 'newest' and maybe some weight saving over 6600 which, in anycase will be minimal with the amount of parts I am swapping.

So back to the chainrings - 6600 - new chainrings - or try the current 10yr old ones I'm using?