Caliper

Ok, with all the manufacturers seeming to change their cable pull ratios at random, I wonder if anyone has ever put together a chart of cable pull ratio? It's hard to dig this info up as a layperson but everything from 9 to 10 to 11 and between mountain and road seems to have all sorts of pull ratios available so one is never certain if one derailleur will interchange with another even of the same brand. Is this something that exists out there?

rpenmanparker 

Why. What good does it do you? Except in the cases where the reviews tell you something is the same or different from something else, it is really of no importance. Different is different. It can't be rigged to be the same.

mcours2006

Something like this?

https://roweroweporady.pl/pobierz/shi...patibility.pdf

Dan333SP

He's just trying to figure out a compatibility chart for mix 'n match groups. That can be important if he buys the current Tiagra levers and finds out that they can't shift a 6600 RD correctly even though they're both 10 speed parts, ect.

rpenmanparker 

I guess I understood that. I think the best bet is to just assume incompatibility except in the very few well publicized cases of known compatibility. Examples are the 8-speed Shimano RDs and 9-speed levers and the SRAM 10-speed RD with 11-speed levers.

banerjek

Sure, but it's always nice to be able to use cheap/free components when you can rather than use the one you're supposed to. I mix and match on 3 of my 5 bikes and it works great.

Darth Lefty 

I have a Shimergo bike with 3x11 Athena Ergos running an SIS 9-speed rear and MTB FD. It works. But that's old news.

I tried via Googling to find info to build an updated table, one that would include all the 11-speed systems now out there, not having anything of my own to actually measure. What I found was a lot of conflict, errors, and lack of info for 11-speed stuff newer than Ergos, epsecially on the MTB side. Errors on cassette spacing in one article will turn into errors in pull ratio in the next article which turn into errors in cable pull in the next one, all without attribution. Actual measurements seem scarce.

You will find all kinds of hacks out there in the MTB world, people running mixes of 10/11 stuff, SRAM/shimano hybrid systems with spacers on the RD pinch bolt to modify the lever arm. This becomes relevant to road bikes because the SRAM brifters are somewhat cross compatible with their MTB stuff.

There are clearly people like WolfTooth who have done the math and experiments.

I have a theory that the new 10-speed Tiagra 4700 brifter should shift an SIS 8-speed rear and I'd love to hear if anyone can try it.

rpenmanparker 

No argument. I am converting my Chinabike to 11-speed right now by just buying the SRAM Red levers, and a cassette and chain. The freehub is already 11-speed and the two 10-speed derailleurs are reputed to do fine with the 11-speed levers. Cheap enough.

k_kibbler

Nothing constructive to add I just think it's wonderful that a poster named Caliper is asking about pull ratios.

Darth Lefty 

So here's what I think I know. A lot of this is based on reading and my own math and not on measurements, I have more time to study than I have money to buy bike parts! Other articles have focused on listing the ratios and shifter pulls and encouraging you to do the math, but the more I play with the idea the more I think that's not really what most people are after.

11 speed cassettes are all spaced the same. This includes both road and mountain cassettes. The road side is pretty well documented and includes all three brands. Some sources claim that the MTB cassettes are wider but that seems to be contradicted by the existence of a few systems out there that can use both road and mountain cassettes... like SRAM Rival 1 & Force 1, and Wolf Tooth Tanpan. Also reinforced by the fact that chain manufacturers don't have different size chains for 11 road or 11 mountain.

10 on down, SRAM and Shimano cassettes have the same spacing but Campagnolo is its own thing.

Shimano 10 and 11 mountain ("Dyna-Sys"), and SRAM 11 speed mountain ("X-Actuation") RD's all have about the same ratio. The 11-speeds give you the capacity for the 40+ tooth cassettes, the 10's are only rated to handle 36. This factoid is confirmed thanks again to the Tanpan, which will work with any of the above. But you can find reinforcement for it all over MTBR, Singletrack, etc. Older SRAM "1:1" RD's have about the same ratio too.

SRAM 10 road and mountain, and 11 road RD's all have the same ratio ("Exact Actuation"). But it's not usefully close to anything else, being squarely in between the road and mountain stuff.

Shimano road 11 speed and Tiagra 4700 10-speed RD's, all have the same ratio. I think this is also very close to Campagnolo's, but this is where my proof is thinnest, because it's based on what I think are rounding errors between other people's tables. That also means that the Shimergo trick could also be a "Shimano-a-mano" trick, where the 11 shifter could run a 9 SIS, and the Tiagra 4700 could run an 8 SIS. Due to the prevalence of Shimano parts this seems like an easy one for some mechanic to try... toss a 4700 brifter on a Claris bike and see what happens.

Older Shimano (road up to 10, mountain up to 9) was called SIS and the RD's all have the same ratio, with an exception for early indexing Dura Ace. So it all works. SRAM MTB RD's that are compatible with this are marked "2:1".

Shimergo is a known trick whereby Campagnolo 10 speed Ergos will run an 8-speed SIS rear, and an 11 Campy will run a 9 SIS. I have the latter running on my bike and the drop-bar mountain bike thread in the C&V section here is otherwise full of them.

Campagnolo had a big change in their RD's in the middle of their 8 speed era and so far as I can learn they've all been the same ever since.

At the front, doubles are really tolerant. You basically set the top ring position with the shifter index and the bottom ring position with the limiter on the derailleur.

Triples are less tolerant. The upper is still set by the index and the bottom still by the limiter, but the middle-top shift is where the problems lie. It seems as though there are two basic families, Shimano road, and Shimano mountain which includes everything else. To detail what I mentioned above I have a Shimergo setup where at the front I have an Athena 11 Powershift Ergo running a SRAM X5 FD and it works just great, the indexes line up well enough. The FD even runs a 53 ring which you really wouldn't expect. The MTB front shifters and FD's are all compatible between SRAM and Shimano. There are also workarounds that don't rely on indexing... some grip shifters have many detents instead of three. Bar-end shifters aka barcons, downtube shifters, and non-Powershift Ergos are all essentially friction on the left/front instead of indexing and can be used with any FD.

Other brands than Campy and SRAM - Micro Shift and Sunrace for example - are pretty much all compatible with the equivalent Shimano product.

A word about chain width... so far as chains know there's really no such thing as a "7 speed" or "11 speed" rear derailleur per se. The internal widths of derailleur chains, set by the rollers and that actually rides on the pulley teeth, is traditionally "3/32" - according to the Wipperman website it's 2.2 mm for 9-10-11 chains and 2.4 mm for 6-7-8 chains. Cog teeth are all 2mm or less, so the chain always has kind of a sloppy fit. And the derailleurs all seem to have plenty of clearance on the outside.

I've spent way too long on this... more later probably

Darth Lefty 

Here are some clues about the Shimano 11-speed RD ratio. Some sources report it to be 1.4 without attribution, however…

Technical FAQ: 10/11-speed compatibility | VeloNews.com a correspondent to Zinn reports “Since I used various rear derailleurs in the past, I made the assumption that the RD-6800 would have the same cable pull ratio as the 5700 and 6700 derailleurs. But when I fitted the RD-6800, I found that, when using 10-speed shifters, it only shifted between 8.5 and 9 cogs instead of 10.”

(7.5 cog steps x 3.95 per cog) : (9 clicks x 2.3 mm per click) = 1.43:1
(8 cog steps x 3.95 per cog) : (9 clicks x 2.3 mm per click) = 1.53:1

Here are some clues about the Campagnolo 11-speed ratio. It’s listed in most tables as 1.5:1

The overall width of a Campy 10 cassette is reported to be 4.15x9=37.35 mm. The overall pull is reported, “Campy 10 shifters pull an average of 2.83mm of cable per shift, but that cable pull is not uniform. The first five shifts are only 2.5mm, the next two are 3mm and the last two are 3.5mm.” = 25.5 mm. The ratio 37.35 : 25.5 = 1.46:1

The overall width of a Campy 11 cassette is reported to be 3.76 x 10 = 37.6 mm. The overall pull is reported to be 25.9 in a post by member DaveSSS. So that’s pretty close to the same thing, 1.45:1

And that’s why I think my "Shimano-a-mano" idea should work. It would be really helpful to confirm it if someone could post the overall pull from a 4700, 5800, 6800, or 9000 brifter. This is pretty easy to measure, you can put a mark on the cable by a cable stop in high gear, and shift all the way to low and measure how far the mark has moved. Or, with internal cables, you can measure the distance from the RD stop to the pinch bolt before and after, and take the difference.