Bicycle Mechanics - Front brake bracket improv

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View Full Version : Front brake bracket improv


ajd
04-29-06, 05:25 AM
I just received a pair of long-reach sidepull caliper brakes (Cane Creek SCR-3L) and... they don't reach far enough when mounted in the existing brake drilling in the fork, which has a very tall crown.

Since this is a commuter ride and I'm not worried about appearance, do you foresee any safety problems if I were to attach a mounting bar under the crown and attach the brake to that? I calculate I'll have a little over 1cm clearance under the brake (too low for a fender), and the brake shoes can be positioned around the middle of the brake arms to hit the rims dead-on.

It's a fixed-gear bike and currently the rear hub is an adapted freewheel, so I'm going to be relying heavily on this brake.

Futuristic ASCII diagram follows (not to scale):



| fork crown |
| |
|| | | ||
=N||==| - - - - - - - |==||N= <- 5mm bolt
|| | | ||
|| ------------------ || <- al/steel bent into a square U
|| || __
=N||N====================N||=| |N= <- brake mounting bolt
||______________________|| | |
|------------------------| | |
| | <- brake
___________________| |________
____-------- | | ----------_____
tire | |

(N == where nuts would go)

(Edit: I want material thin enough to bend with hand tools (I don't have access to welding or serious metalworking tools) but too thick for a panic stop to flex.


operator
04-29-06, 05:48 AM
Go to store, buy tektro long reach dual pivot front brake caliper, should run you about $20-25.
Or you can buy a drop bolt from sheldon brown which is like $50 for a pair. He also has a homemade drop bolt solution out of reflector brackets.

Personally i'd just go with the latter, or get a new brake.

HillRider
04-29-06, 06:27 AM
Sheldon's improvised drop bolt made from reflector brackets implies your idea is both practical and probably a lot stronger. Make the vertical parts of your bracket as short as possible and use the heaviest gauge metal (preferably steel, not Al) you can manage.

BTW, there are "extra long reach" brakes still out there. Some older bikes used either center pull or side pull brakes with reaches as long as 70 mm. Searching E-bay or an older LBS may locate a pair.


ajd
04-29-06, 07:19 AM
Sheldon's improvised drop bolt made from reflector brackets implies your idea is both practical and probably a lot stronger. Make the vertical parts of your bracket as short as possible and use the heaviest gauge metal (preferably steel, not Al) you can manage.

BTW, there are "extra long reach" brakes still out there. Some older bikes used either center pull or side pull brakes with reaches as long as 70 mm. Searching E-bay or an older LBS may locate a pair.

Thanks. The bolt will have to have to be no more than 4mm beneath the underside of the fork crown for that 1cm clearance brake arch -> tire (with the current tire...), but that much doesn't seem hard to do. Now that I think of it, this should also give me the ability to swap from 27" to 700 wheels if that day comes.

Sheldon Brown
04-29-06, 12:15 PM
See: http://sheldonbrown.com/home-drop.html

Sheldon "Materials Available" Brown

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