My roady came with Cannondale C4 brakes. I keep having problems with them and am looking to replace them. I was going to grab some 105s but am not sure they’ll be compatible with my levers.

I have the 2011 Sora shifter/levers (the ones with the little thumb shifter). Looking at the blurb on the Merlin site it says;
Must be used in conjunction with ST-5700, ST-6700 or ST-7900 STIs for correct leverage ratio

Will I be able to get away with using 105 calipers with the Sora levers or should I look at a lower spec caliper?

105’s will work fine.

105’s will be fine, swap out the stock pads for kool stop Salmons or Swiss stop for better performance though

Thanks for the advice.

I’ve found this compatibility chart (at the bottom of the first page) which suggests Sora ST-3400 aren’t compatible with the 105 BR-5700.

Why do Shimano say no? Are they just being overly picky, or will there be something noticeably incompatible about them?

Slightly different cable leverage/pull in different sti’s . Means you won’t get optimum power but they will still work

I’m still struggling with what to get 🙂

I’m not sure if I need long or short drop…

Measuring from the mounting bolt to the mid-point on the pad is about 55mm, so presumably long drop… But my existing caliper looks to be able to cope with a range of 40-60mm, don’t all calipers do that?

If you don’t plan to replace your STIs get the BR-5600s, they’re designed to work with the older STIs like yours.

Found my answer.

http://sheldonbrown.com/calipers.html#reach

Struggling to find the br-5600s, there’s one seller on eBay, but that’s all I can find.

What problems are you having with the C4’s?

If it’s simply a lack of power then it may just be because the standard pads are shite so swapping ’em out for something decent makes a world of difference. Mine have been great since putting SwissStop greens in.

Surely pulling a cable is pulling a cable, your hand modulates the force.

The stopping power has been fairly bobbins, but they seem to have lost their ability to spring open. I’ve cleaned and lubed all the pivots and checked the cables are moving freely, but the rear refuses to spring back open.

I had the same with these brakes. Swap em for 105’s, it will be fine

Thanks for the help, I’ve ordered a 105 br-5600 rear from eBay.

Surely pulling a cable is pulling a cable, your hand modulates the force.

Nope – different leverage ratios – cantis and v-brakes are different too.