Shimano 5700 shifters with 6600 derailleurs

bianchi_dave

Hi All
I've just removed 105 5700 shifters from my 'best,' and contemplating fitting them to my older bike which runs Ultegra 6600, the main reason being for aesthetics, in that I can run the gear cables under the bar tape. I've done a bit of online research and there seems there may be an issue due to the newer groupsets (with under the bar tape gear cables) having a stronger spring in the derailleurs, to compensate for the tighter curves in the cable routing. Even with both being 10 speed, will there also be an issue with the pull ratios of the different generations of shifter?
Is anyone running such a set up, or anyone tried it and found it adversely affected shifting performance?
Cheers
Dave

Semantik

it will shift just the same whether it's 6600 or 5700 shifters,
if there were differences in the action of the shifters then Shimano 10speed cassettes from the different generation groupsets would not be cross compatible as they are,
Differences in pull ratio in relation to STI shifters more usually relates to the pull ratio of the brake levers and calipers.

bianchi_dave

Thanks Semantik. I had read there may be a problem with the front derailleur in particular, when shifting from big ring to small, as the older gen groupsets had a smaller return spring. Guess I'll just have to try it and see - if the cable internals are well lubed it should help. Cheers

andy_wrx

Dave, I think you are right with your original observation about the mech springs - Shimano say they're not compatible, but I suspect it's because there's a stronger spring in there to overcome the additional friction of the under-tape cables of 6700/5700 - particularly if not maintained...

I run 6600 shifters with 6700 front mech and I may have a 5700 rear, can't remember, but that's the opposite to you.
But the pull-ratios are of course identical.

Yeah, cable it up with clean cable runs with no really tight kinks, keep it all clean and lubed and I'm sure it'll be fine.

bianchi_dave

Thanks Andy. I'll give it a go and if its no use just go back to the 6600 shifters. Being an older bike, it has external cabling so probably less cable friction in any case, without having to bend into (and out of) the down tube. Cheers

bianchi_dave

Just a quick update in the unlikely event anyone happens to be in the same position - I fitted the 5700 levers with the 6600 mechs. Made sure the new cables (inners and outers) were well lubed, along with the cable guide under the bb, and everything works flawlessly.