Shimano 10sp shifting parts

[hamishm]

Hello Shimano compatibility experts,

I have two questions about new 10sp shifting parts in an 11sp world...

I'd like to replace the 6700 crankset on one with compacts. Are RS500 11sp ok (and not too horrible)? Or else 5800? I think I read Duck saying mixing 11 sp chainrings onto 10sp was all good on this very forum but I can't find it now.

Secondly I need to replace a 6700 right shifter. What's the cheapest I can still get? I found a Tiagra 4600 online at an acceptable price, which should work right? But 4700 won't? I'll look around for a cheaper 5700/6700 second hand too.

Thanks.

[Duck!]

Try this thread for all the details.

Yep, cranks/rings aren't fussy. 2nd-gen 10-sp. (e.g 6700) & 1st-gen. 11-sp. (9000 & derivatives, not R9100/R8000) chainring spacing is pretty well identical, and ramping is similar enough to not cause problems.

4700 Tiagra uses the same leverage ratio as 11-sp. stuff, which means it pulls more cable to cover the same 3.95mm sprocket spacing than other 10-sp. Which means you'd need to replace the rear derailleur as well. All other Shimano road 10-sp. is interchangeable.

[hamishm]

Thanks Duck. Do you have an opinion on whether the RS500 cranks will be ok? I don't really care about the weight and I'm not sprinting on them...

[Duck!]

They'll be fine.

[hamishm]

Try this thread for all the details.

Thanks Duck, that's a great post.

Lennard Zinn has some posts about 10/11sp compatibility over at http://www.velonews.com/2015/03/bikes-a ... ity_362722 too.

[hamishm]

6800 crankset with 10sp in the same boat I guess - even R8000?

[Duck!]

6800 & other 1st-gen 11-sp. cranks are pretty much the same chainring spacing as 2nd-gen. 10-sp. (eg. 5700/6700/7900), so completely compatible. They will also work in 1st-gen. 10-sp. (7800/6600/5600) & 9-sp. systems, but those older front derailleurs don't play very nicely with the wider chainring spacing, so it's best to generationally match the front derailleur to the crank. Shifter compatibility is fine.

R9100 & R8000 cranks have a further increase in chainring spacing over 2nd-gen. 10-sp/1st-gen. 11-sp, with the small ring slightly further inboard. The official word from Shimano is that it should be OK with a 1st-gen. FD (they won't tell you about 10-sp. compatibility, but it's there) on most frames, but some frames with a sightly thicker seat tube may not allow an older derailleur to shift in far enough, in which case a matching new model derailleur, which has greater inward swing ability, needs to be used. Both generations of 11-sp. FDs, and by extension 4700 Tiagra (which could be considered 3rd gen. 10-sp.) and R3000 Sora which also use the long-arm design don't match perfectly well with the older shifters, but can be tuned acceptably.

[Duck!]

Lennard Zinn has some posts about 10/11sp compatibility over at http://www.velonews.com/2015/03/bikes-a ... ity_362722 too.

There is one section in that post where Lennard gets it wrong purely by not thinking outside the box; the question regarding upgrading from 10-sp. to 11-sp. and keeping the triple. Yes it's possible, but requires mismatched shifters and of course carrying over the front derailleur, as none of the 11-sp. groups offer a triple. The closest cosmetically would be the 4703 Tiagra.

[hamishm]

Thanks Duck. I need to replace my 6750 chain rings, planning to get a set of those else switch to 6800 then.

[jasonc]

Hamish - i have a brand new 6750 if you're in brissy

[hamishm]

Hamish - i have a brand new 6750 if you're in brissy

Got some 6750 rings from another forum member here in Melbourne but thanks for the offer.