2/22/17 6:46 PM

I still had the 7800 calipers on the Addict when it was adorned with the 11s Di2 upgrade. This is a cable pull mismatch.

I also have the newer pull 6700 calipers on another bike with 10s STis, a mismatch in the opposite direction. This one gives a lot of extra power, some might say too hard to modulate. I like it and have no problem with the modulation or lock ups personally.

The Addict mismatch in the other direction was a lot less confidence inspiring on hard grabs. Although I had no problem stopping, but it took a lot more hand. Which I have the gorilla variety on the end of my arms.

Upgraded the Addict to 7900 correct pull calipers today. I thought my observations might be of interest. The improvement is there. But I did have cool-stop orange shoes which was a definite improvement over the original 7800 shoes given the pull ratio mismatch. I find the 7900 calipers a step or two again better than the 7800 calipers with the cool stops.

Now I need to put cool stops on the 7900 brakes? But the newer pads on the Shimano brakes are a lot better than the previous versions. The 6700 calipers still have them. They seem so good as to lessen the need to go cool stop right away unlike the previous Shimano shoe versions.

2/23/17 7:03 PM

Wish I had the cool stops on there dodging hail and rain for the last 10 miles of my jaunt today. Of course happy to get out, but maybe shoulda brought that rain gear I looked at when I headed out.

2/23/17 7:04 PM

I got confused there when you said that 6700 calipers were a mis-match with 10s levers, since 6700 parts are all 10s variety!

So I guess maybe you meant 6800 calipers?

Changing the pads can make a significant adjustment to power, but grippier pads seem more prone to squeeling as well.

I often bend (relax) the return springs on vintage calipers, which makes a seemingly disproportionate improvement in power vs. effort.

2/23/17 7:06 PM

I thought the cable pull change happened with last 10s versions? 57/67/7900, no?

I should have said 6700 calipers with 6600 STis above, sorry for that ambiguous data.

2/24/17 12:15 PM

BTW, Fun factoid: I tried to get a few 1st gen Shimano under tape STIs to shift well, only worked well for short periods of time regardless of orig cables etc.. For myself I got the previous version [6600-03] shifters to mix with the 6700 group and was happier for it.

In fact and IMO, the 6703 triple group using 6603 STis was one of the best shifting bikes I have ever lived with. [that group on Klein Carbon then disc Roubaix]

And a triple that behaved better than a lot of doubles prior. It cured the OSBB Roubaix which with compact doubles on would chain drop if trimmed to shift properly. Never tried a 11s crankset though, offed it pretty quick as all may recall.

Sat my disc Roubaix on Craigslist recently. Looks like he never rode it since buying it from me, what .. 1-1/2 years ago? 450.00 less asking than he paid me for it. I knew I needed to loose it before Spesh redid it as a lot better bike. ;)

2/25/17 1:15 AM

I seem to recall that their was a small claimed change in cable pull when 10s came out (as reflected by dotted line?), but the larger change with 11s was supposed to force the use of 11s calipers with 11s levers and vice-versa.
The newer leverage ratio reduces cable elasticity loading, and the longer cable travel further reduces the effect of any such stretching as felt at the lever, so an overall less-spongey lever feel results.
Pad flex can also effect the feel at the lever, with longer, thinner pads reducing flex.
The advantage going to disc brakes becomes smaller with each revision of the standard caliper brakes, though carbon rims and sustained wet conditions still gives discs an edge.