ilikeriding Posted January 11, 2008 Report Share Posted January 11, 2008 (edited) Used my 180mm for about 2 weeks and the disc has bents its self into a bowl shape from the force of it stopping, now its rubbing the caliper and is gonna make the pads wear wonky.Anyone else had this problem?Reckon they'll replace it? Edited January 11, 2008 by jebend Quote Link to comment Share on other sites More sharing options...
psycholist Posted January 11, 2008 Report Share Posted January 11, 2008 (edited) Is the disk mounted to rotate in the right direction? Usually there will be an arrow on the disk to say which way it turns. If not the curved spokes should point in the direction the disk turns while you're going forward as you follow them from the hub to the braking surface of the disk. Reversing the disk may fix the problem anyway (Reverses the load that's causing the bending, possibly curing the disk rub - once it bends the other way you'll have to reverse the disk again, so long term (or possibly not that long term) the disk will break). I doubt if that would be a mandatory warranty job, to my knowledge the BB7 is not sold as a trials brake - try the place you bought it first, if they're sympathetic they might be willing to sort it regardless. Edited January 11, 2008 by psycholist Quote Link to comment Share on other sites More sharing options...
ilikeriding Posted January 11, 2008 Author Report Share Posted January 11, 2008 (edited) ahhhh yeah, didn't think of turning it the other way round! (it is the right way atm though.) Edited January 11, 2008 by jebend Quote Link to comment Share on other sites More sharing options...
2sixstreet Posted January 11, 2008 Report Share Posted January 11, 2008 Ive seen this happen before - not quite a bowl shape though. Can be bent back no problem. It sounds like your adjustment was a bit out so was pushing too far over one way. Ideally it should be set up to slightly drag or just off. It doesnt have far to flex then when the other side comes on. I wouldnt recommend flipping it over - they're designed to rotate that way for a reason. Quote Link to comment Share on other sites More sharing options...
basher Posted January 11, 2008 Report Share Posted January 11, 2008 Ive seen this happen before - not quite a bowl shape though. Can be bent back no problem. It sounds like your adjustment was a bit out so was pushing too far over one way. Ideally it should be set up to slightly drag or just off. It doesnt have far to flex then when the other side comes on. I wouldnt recommend flipping it over - they're designed to rotate that way for a reason.It happened to a mate and it he had it where the non moving pad wasnt close to the disk so it would push over, BUT the disk bent the other way. Its not to do with the rotar being pushed over by the moving pad. We think its to do with the disk mount no being perfect and needing facing. Eventually the disk will just snap. Quote Link to comment Share on other sites More sharing options...
2sixstreet Posted January 11, 2008 Report Share Posted January 11, 2008 It happened to a mate and it he had it where the non moving pad wasnt close to the disk so it would push over, BUT the disk bent the other way. Its not to do with the rotar being pushed over by the moving pad. We think its to do with the disk mount no being perfect and needing facing. Eventually the disk will just snap.Im guessing in that case the 'spokes' of the rotor were flexing over towards the static pad each time. The spokes would bend much more easily than the braking surface. The spokes are then bent but spring back over to the active pad side as the base of the spoke will bend near the centre of the rotor not the braking surface. Kinda difficult to explain. Quote Link to comment Share on other sites More sharing options...
craigjames Posted January 11, 2008 Report Share Posted January 11, 2008 never seen this before, the only issue ive had with my 08 bb7 was that the calliper actually flexes as you pull the lever. not good. still laods of power, but a bit too spongy. Quote Link to comment Share on other sites More sharing options...
Shaun H Posted January 12, 2008 Report Share Posted January 12, 2008 Yeah the 08 BB7s are actually two piece rather than one like the older ones. Hence being cheaper (I think?).I helped someone out with theirs on a Brum ride and it flexed quite a bit! Still worked pretty good though.As for the rotor bending, if it's not been hit then it has to be to do with how the brake is set up, or something to do with the amount of flex they have. Double check it's set up square (although this might be quite hard now!) but if it's caused by flex, there's not alot you can do really. Quote Link to comment Share on other sites More sharing options...
PaRtZ Posted January 12, 2008 Report Share Posted January 12, 2008 sorry to hijack this thread but im having issues too The way I set it up (this might help jebend)1: Undo the 2 bolts that let you set the caliper up in the right place, so the caliper can slide left + right2: Make sure the inner pad isn't compleltly wound in, just one or two clicksout so the disc wont rub on the caliper itself when the pad wear down3: Now wind the outer pad all the way in, so that it touches the rotor, and will also pull the inner pad against the rotor too. The disc/wheel shouldn't turn at this point4: Tighten the caliper bolts to fix it in this position5: Slacken off the outer pad adjuster a few clicks and you're good to goNOW my problem is, I still have a spongy feeling in my lever and I think the cable has slack in it, but whenever I go to pull the cable through, it wont come through anymore. Its as if the tightening plate causes the cable to have too tight a angle, because the cable has to sort of bend round the caliper arm before its tightened. Then as I pull the caliper a bit, the angle becomes less and so it can take up the slack - spongeAnyone else got similar problems? Quote Link to comment Share on other sites More sharing options...
basher Posted January 12, 2008 Report Share Posted January 12, 2008 Dont really get what your problem is, but try setting it up like this, loosen bolts off screw the inner pad ina few times so the rotar is int he centre of the caliper (you may need to screw it a few times as after youve set up the brake the pad will be up against the rotar touching). Now pull the leaver inso the brake is on you may need to adjust the moving pad in or pull cable through to get the pad to hit. keep the leaver pulled in pritty tight and tighten the bolts up. Now move the inner pad out away from the rotar and set the brake to bite where you want. And if your using the adjuster on the lever that pulls the cable it will create sponge. That way has always worked for me Quote Link to comment Share on other sites More sharing options...
ilikeriding Posted January 12, 2008 Author Report Share Posted January 12, 2008 sorry to hijack this thread but im having issues too The way I set it up (this might help jebend)1: Undo the 2 bolts that let you set the caliper up in the right place, so the caliper can slide left + right2: Make sure the inner pad isn't compleltly wound in, just one or two clicksout so the disc wont rub on the caliper itself when the pad wear down3: Now wind the outer pad all the way in, so that it touches the rotor, and will also pull the inner pad against the rotor too. The disc/wheel shouldn't turn at this point4: Tighten the caliper bolts to fix it in this position5: Slacken off the outer pad adjuster a few clicks and you're good to goNOW my problem is, I still have a spongy feeling in my lever and I think the cable has slack in it, but whenever I go to pull the cable through, it wont come through anymore. Its as if the tightening plate causes the cable to have too tight a angle, because the cable has to sort of bend round the caliper arm before its tightened. Then as I pull the caliper a bit, the angle becomes less and so it can take up the slack - spongeAnyone else got similar problems?need a better cable maybe?, I'll have a bash at setting it up like that Quote Link to comment Share on other sites More sharing options...
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