Guys, I'm only registered on this forum, so hope you don't mind me posting this here. CBR600 Got a slight vibration on my front brakes. I've stripped the callipers and all are working very well, so no problems there. I've seen there are companies out there who straighten discs. Do they actually straighten the disc or do they put full floating adapters on? Anyone any experience?
Think you'll find they skim the disc flat again by machining, if the disc is near the lower thickness level it won't be possible to do
Skimming discs was the thing years ago, the disks were as thick as a Dockers sandwich. But today with weight such a priority the tolerances are fine, as SPS has said may not be viable. By the time you've messed on I would suspect new discs may be the way forward. or if on a tight budget, Patten/ used. Good luck. Mike.
Ok guys, I've now run a DTI over the discs and the run out is 0.5 - 0.55 on both discs. I wouldn't have thought this much would cause a problem? What do you think?
Anything more than 0.2-0.3 is going to cause problems ... I'm assuming there is no pad build up in the discs that can cause this issue?
No build up, I've just pressure washed the discs and bobbins to make sure there's no dirt preventing the disc floating. I'm getting a slight judder when braking at speed, but lower speed it grabs and releases, grabs and releases.....
Had a very similar sounding problem on my mates Blackbird, he uses it through the winter and sometimes doesn't wash it off. anyway finished off with the pads sticking to the discs, He was experiencing similar things to you. He cleaned the discs, made quite a good job (I couldn't see any residue) and still had the problem.... I took it out and really gave the brakes a workout, getting them to fade state. It's okay now. I'm not suggesting you do the same, but just a pressure wash may not be enough, perhaps some brake cleaner and a pan scrub. before starting to chuck money at it. Mike.
If the disks are warped, you can try fixing with a hammer! Don't hit the disk (obviously), hit the buttons the disk floats - If done carefully, you bend the carrier, which forces the disk to run true. I've done that on a couple of bikes, including an R6, R1 and a bandit.
Well binned_it, laughed when I saw your post, so ordered some new discs. Then, thought......I wonder if it is possible to hammer them into shape.......1hr later, discs are to within 0.15mm!! Gonna hang onto the discs for the moment, see if I need them. Cheers fella
Glad it worked. It was a guy who raced bikes that showed me; I was sceptical too, but when he explained that the aim was to bend the carrier, and that the buttons the disk float on are very hard and can be safely tapped with a hammer, it made sense. It only has to be slightly out before it feels awful to ride, so it's not like you have to hammer 6 bells out of the disk to straighten again. Spin the wheel, watch the disk touch the pads, mark the bit that seems to be the problem, and carefully tap straight. I expected them to bend back or cause issues again, but it was never a problem. Happy days.
There wasn't really a problem till I went the IOM. I used an elastic band on the brake level to keep the front wheel fron moving on the ferry. I'm wondering if this caused the issue.
That's interesting binned_it. I have exactly the same problem on my RR7! Braking at high speed vibrates the hell out the bike and low speed it "lurches" to a halt. She only has 13000 on her and had new discs 100 miles ago, I presume from the test cert it was warped discs but maybe not? She's back at the dealers under warranty and he confirmed the right disc is only 1mm out but the left disc is outside of tolerance.
Hi Tonic, so the hammer method worked then? I haven't said owt to the dealer. I'll let him and EBC replace them lol He mentioned it was 1mm out is all didn't say what the left one was:-( If it happens again I know what to try tho
Yeah, it worked a treat. When I'd finished, they were both about 0.15, I could still feel a very slight judder, but they've got better and better over the past 500 miles and now they are absolutely perfect. I now have a full set of EBC discs, pads and calliper seals I need to put on eBay (for my CBR609fx). I won't be doing it until I've upgraded to a blade tho....
Just an update...EBC are replacing the discs. We'll see how it goes when I get her back. Thanks for the help and advice guys, appreciate it
Ok so I have an rr4. Braking spot on at high speeds,but when say I'm pulling up to a junction fairly quickly,the last few metres brings the most incredible juddering if I keep the front brake at the same position. Would you suspect warped discs too?