Dudes, a couple of months back I had my bike in at the shop and they mentioned that the front brake was rubbing a bit so they cleaned it up for me. When I ride the bike i can hear like metal on metal scraping sound especially as I come to a stop, it doesn't always do it and I have never heard it when I get the bike out ready to go out. To me it sounds like the noise is coming from the bottom of the engine but its an external noise, its not the engine, it almost sounds like it could be a wheel bearing or maybe the caliper/s are sticking a little and its this that causes the noise. My question is what do i do about it? is it as simple as striping the caliper down, cleaning it all and piecing it all back together (not done by me) or could that only be a temp solution? My mates caliper locked on track right in front of me and I don't want that to happen to me on the road. TIA
You need to get the front off the ground and spin the wheel to see if there is any binding. If the calipers are caked in brake crud then remove the pads and with a toothbrush and some brake cleaner get scrubbing around the piston, ensuring not to get it on the caliper itself as it can take the paint off. Caliper pliers are good as you can twist the piston around to ensure they are moving freely and to clean them: http://www.ebay.co.uk/itm/Sealey-VS...893967?hash=item2ca8d1f88f:g:WM4AAOSwEK9XAX7K Check the discs look good also when spinning the wheel and not warped.
Tried this last night and the wheel spins pretty freely, it stops after a half turn ish but from what I have seen they all do that, the disks look straight enough so I'm not sure what this noise is? it sounds like it comes from the front sprocket area?
Chain adjusted and aligned ?? Loosen pinch boots on front forks push on front suspension ( not with front brake on ) and then re-tighten pinch bolts . Chain lubed ?
Is that half a turn even with a really hard spin? That's bad dragging - you should get at least two turns really. I had a very similar binding issue on my bike, especially on track which made things worse and it took ages for me to work out that it was actually a really simple fix: Before realising what it was, I replaced pads to no real avail, bled the system a number of times, had a shop look into it plus changed out the slightly warped rotors with upgraded Brembo ones having excessively dragged them on track to the point they went blue, glazed the pads and even pushing the bike along was difficult! It turned out that even though I'd cleaned the pads and discs up 'properly' so they appeared spotless, I still had a build-up of copper ease/brake dust tucked away in the grooves where the brake pad tabs slide (on brembo M50 calipers but I think yours are similar). This was preventing the pads from retracting back properly upon releasing the lever, thus causing the binding problems. I used a mix of water and washing powder (advised after a conversation with a company that services calipers - they use Daz!) to clean them up, plus cotton buds, toothbrush and screwdriver with fine Scotchbrite wrapped around the tip to reach right into the grooves and fully clean them up. Reinstalled pads after fully drying everything with a little copper ease on the back of the pads only, and after bedding in I now achieve a good 6 revolutions of the wheel before it comes to a halt when spun on paddock stands. Hope that helps, as this issue plagued me for ages! Sam
Wow, 6 spins? I could probably get one spin if I spun it hard so maybe they are rubbing, I can hear a rubbing noise when I free wheel the bike but it does move freely and the noise isn't bad, it's a completely different type of noise whilst riding, much deeper but only seems to come on as I'm coming to a stop and not always. It'll probably do it 3 or 4 times in a couple of hours worth of riding which is why I'm not convinced it's the brakes. Braking also doesn't seem to make it either do it or stop doing it. I think my callipers are not fully retracting but I don't think that's the noise the more I think about it. I am having them cleaned and painted on Friday so I may ask the guy if he can clean the internals also. Am I right in thinking that I the pistons are removed to be cleaned I will need a calliper rebuild kit or at least new seals?
Chain is new and fitted by a bike garage, its lubed as well. What are pinch bolts for? im still new to bike maintenance so loads of stuff i don't yet know.
You want to get yourself a haynes manual or download a service manual from tinternet matey. You should ideally tighten everything to correct torque settings. It's easy to overtighten pinch bolts and crack the lower stanchion. If you think the noise may be coming from the front sprocket area then take off the sprocket cover and check nothing rattling around in there and everything looks okay. Pinch bolts clamp the forks to the wheel spindle. Yep, if you are removing the caliper pistons then you need a rebuild kit to fit new seals. Put two fingers over the top yoke above the large nut and your thumb under the bottom of the top yoke. Then with the brake on rock the bike back and forth and see if there is any play felt if so the bearings could be worn.
I have a Haynes manual but haven't looked into anything for this as I don't want to mess with my brakes, I'd rather pay someone who knows how to do them right than have a go myself and find I cant stop from silly speeds. I'll have a play around with the top yoke etc. Thanks for all your input guys!
