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Front disc mount placement??

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Front disc mount placement??

Old 11-12-14, 01:40 PM
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jawnn
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Front disc mount placement??

Can any one tell me if this will work in reverse on the right side of a drop out that will have a large amount of rake with short trail?? (where I can't possibly use this method.)

And why is this different than the rear brake mount? what kind of adapter do I need ?




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Last edited by jawnn; 11-12-14 at 02:08 PM.
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Old 11-12-14, 03:52 PM
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I think there is a concern with that geometry that it levers the wheel out of the drop. But that is a just a conventional problem simply ensure that your axle, or slot geometry, or lawyer lips, give you what you need to be safe.

If you consider that the calliper is working somewhere on the disc between the two mounting holes, and that when it is applied it becomes the new center of rotation, rotating the lower axle out of the drop along and arc from the calliper grab point through the axle. Then you can see that there is negative rake to the slot in that loading, or maybe it is just neutral. It can actually be worse in some conventional placements, which is why some frame makers won't install them.
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Old 11-12-14, 05:22 PM
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I've seen a Photo somewhere of a Tandem bike with the disc caliper in front of the right fork blade ..
torque forces push it into the dropout more , rather that pull outward.

read that Thorne wont build a raked blade disc fork only straight ones , on the left the brake is un bending the fork a bit ../
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Old 11-17-14, 03:05 PM
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what?

ok I brain stormed the idea, and found a way to put the brake on the bottom. I had to reduce the trail to half inch.

I think maybe that the wheel pulls on the brake more than the brake pulling the wheel. otherwise I may have to put the slot for the axle in different position.

Last edited by jawnn; 11-22-14 at 12:19 PM.
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Old 11-17-14, 04:13 PM
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Why on the Bottom? not just put it on the front of the fork blade, above the dropout? , you are overcomplicating things..

you going to cut that out of 1/4" thick steel plate? How?
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Old 11-17-14, 06:37 PM
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you can make something like that with hand tools and a drill press. When I had more energy and less sense, I would do things like that all the time

If the dropout points in the wrong direction, the force pulls the wheel out of the dropout. The force at the wheel axle is equal and opposite to the stopping force, so it doesn't matter who is pushing on who
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Old 11-19-14, 01:32 PM
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I've put disc mounts on the front of the right leg - it means the braking torque is forcing the axle into the dropout instead of out, it also means that the back of the fork leg is free for rack and mudguard mounts.

Im not sure why I don't do it more often to be honest - habit, and so it matches the rear probably.
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Old 11-19-14, 02:25 PM
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Think of it simply, The brake pad becomes the new touque center axis, when you apply the brake ..
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Old 11-20-14, 03:10 PM
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If I could find some diagrams of where to put the holes i could use a larger rotor. but I may need a computer to place the thing perfectly.
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Last edited by jawnn; 11-22-14 at 12:20 PM.
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