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[Closed] STI levers with MTB mechanical disc brakes

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[#7959426]

I know the lever pull is 'wrong' to be using MTB brakes but my bike has Hayes CX comp mech brakes and they are worse than useless!

I have compressionless cables, new sintered pads, and have fitted a 180mm front rotor to get more power but they are utter crap still. Firm lever pull and an initial first grab but no real sustained power to them. The pads surface area is tiny which I think is the problem.

Before I splash £200 on TRP Hy/Rd I have some MTB Shimano mechanical brakes in my junk box.

Im not bothered about modulation so much and I like my brakes 'on straightaway' and with plenty of POWER! - will they work at all?


 
Posted : 22/07/2016 8:06 pm
 cp
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Don't do it. Road levers don't pull much cable. You can set the brakes to work (it needs little tweaks to get it though) but as soon as the pads start to wear or the cable stretches a bit you'll get no brake action as the lever can't pull enough cable to compensate.


 
Posted : 22/07/2016 11:40 pm
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You can get BB7 mechanical disc brakes in either road or MTB pull.


 
Posted : 22/07/2016 11:45 pm
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I've dug them out and just been comparing how much difference there is in the arm length between the Hayes calipers and the shimano junk box mtb ones and i reckon its about 10mm.

I can understand why they wont work now, however i feel a tinkering/fabricating sesh coming on tomorrow!


 
Posted : 22/07/2016 11:49 pm
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They will work I've done it but you need to adjust regularly. And the window between slight stretch and no brakes is dangerously close.

What wrong with the Hayes. I have them and once bedded in are as good as my bb7s on the other bike


 
Posted : 22/07/2016 11:58 pm
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I chopped ~10mm off the actuator arm. Ugly but effective - transformed the feel using some old 9sp Tiagra brifters.
This was using a set of cheapo tektro calipers.


 
Posted : 23/07/2016 12:05 am
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"The pads surface area is tiny which I think is the problem."

theres a small matter of an equation that disagrees no ?


 
Posted : 23/07/2016 12:10 am
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My BB5's were much improved by sintered pads but they're still only '[i]alright[/i]' I did have a vague plan to take some of the spare shimano hydraulic MTB brakes littering my garage and bodge a poor man's v-twin or hyrd everything is there, caliper, master cylinder, I would just need to make a modified lever and hack the lever body about a bit... In theory anyway.


 
Posted : 23/07/2016 1:08 am