Mountain Biking - New Disc Brake Drag

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View Full Version : New Disc Brake Drag


mikejo
02-09-07, 09:46 PM
I just installed new 2007 Juicy Carbons on a new frame (first time doing this). The directions were very simple. However, the rear brake still rubs. It appears as if the calipers need to be closer to the wheel or the rotor needs to come closer to the frame. However, neither of these are possible since everything is "maxed out" already.
It seem like two 1mm spacers/washers either to move the calipers in, or six washers to move the rotor out, would work. Anyone ever experience this or have an idea?

I search the mechanics and this forum, and found nothing that deals specifically with this issue.


mx_599
02-09-07, 10:05 PM
I just installed new 2007 Juicy Carbons on a new frame (first time doing this). The directions were very simple. However, the rear brake still rubs. It appears as if the calipers need to be closer to the wheel or the rotor needs to come closer to the frame. However, neither of these are possible since everything is "maxed out" already.
It seem like two 1mm spacers/washers either to move the calipers in, or six washers to move the rotor out, would work. Anyone ever experience this or have an idea?

I search the mechanics and this forum, and found nothing that deals specifically with this issue.
yes. i had same problem. i did as you mentioned. washer to move caliper towards wheel. it's not a bad thing.

however, i was fortunate to have varying thickness Hope washer/shims. the ones that worked for me were roughly half thickness of a common washer. this put my caliper centered on the lateral slots. prior to that mine was maxed out as well.

so....if common washers are too thick, you might have to get thinner shims. i guess people have used soda/beer cans, but that would be pain. if you are not in a hurry, you can order a nice little bag of Hope shims from here:

http://www.monkamoo.com/Hope%20Parts%20Pages/hopecaliperparts.html

i know it seems like a lame thing to mail order, but i couldn't find shims at local places either.

Az B
02-10-07, 07:50 AM
I had the exact same problem. I used washers to center the caliper and it works fine.

You can get shims from many auto or motorcycle performance shops.

Az


mikejo
02-10-07, 01:37 PM
I found some washers laying around an moved the calipers in. I just manually tried to center them over the rotor. It is better now but not as good as the front.
I guess I could move the wheel over on the axle as well or should I not do that?

mx_599
02-10-07, 02:08 PM
I found some washers laying around an moved the calipers in. I just manually tried to center them over the rotor. It is better now but not as good as the front.
I guess I could move the wheel over on the axle as well or should I not do that? i wouldn't do that.

do you mean the washers "over shot" the best position? you should be able to get it as perfect as the front if you have different thicknesses of shims to play with. it doesn't take much to go too far. that is why mine were thinner. i just happen to have hope brakes too so i had the shims handy.

mikejo
02-10-07, 08:17 PM
i wouldn't do that.

do you mean the washers "over shot" the best position? you should be able to get it as perfect as the front if you have different thicknesses of shims to play with. it doesn't take much to go too far. that is why mine were thinner. i just happen to have hope brakes too so i had the shims handy.

The washers were not enough; they were very thin. I went to ACE Hardware and got two washers about 1+mm thick. When following the installation directions with new washers, it still rubbed. Therefore, I just spun the wheel fast and listened. When I heard the best sound (which is no sound) I tightened. Pretty good so far. Both F and R rub a little as they rotate-- say 20 degrees out of the 360 degrees of the rotor. But what I hear, this may be normal.

alumrock12
02-10-07, 08:25 PM
well, now that you have your rotor in somewhat the correct position, you can fine tune the caliper so that you have the right amount of spacing on each side. what i do, is loosen the bolts keeping the caliper from moving side to side, then apply pressure downwards to keep the caliper body down. now i simply let the pads do the work, by compressing the brakes against the rotor, then tightening the caliper body down, once tight, release the pads, and there should be equal space on each side of the rotor.

if that doesn't work, you just gotta adjust it by eye.

mikejo
02-10-07, 08:31 PM
well, now that you have your rotor in somewhat the correct position, you can fine tune the caliper so that you have the right amount of spacing on each side. what i do, is loosen the bolts keeping the caliper from moving side to side, then apply pressure downwards to keep the caliper body down. now i simply let the pads do the work, by compressing the brakes against the rotor, then tightening the caliper body down, once tight, release the pads, and there should be equal space on each side of the rotor.

if that doesn't work, you just gotta adjust it by eye.

That is what I did but I was not compressing the breaks, I was letting the wheel spin. When I did what you suggested (and so do the directions) it was rubbing quite a bit after tightening. I'm wondering if my brake tab is not welded on completely straight.
BTW, nice looking bike. I'm building up a Kelly. Steel is real.

mikejo
02-10-07, 08:56 PM
This message is hidden because R. Danneskjöld is on your ignore list.

I'm sorry, I can't seem to read your post. Many moons ago I realized you are either on some good medication or either in need of some good medication. I have a friend who can change your prescription or at least give you a number to call for help.

mikejo
02-10-07, 08:58 PM
Still can't read any posts by R. Danneskjöld for some reason.
Maybe if you type louder.