Hi all. I need to replace my front discs on my 899 this year and was wondering if anyone has fitted 330mm instead of the standard 320mm. I see no reason why they won't fit. I'm guessing I just need to fit some caliper spacers to compensate the larger disc. Would 5mm spacers work or should I go for 10? Would there be any gain in performance? Any information on this mod would be much appreciated. Thanks.
I don’t know the answer to your questions however, if you do it you would need 5mm spacers under the calipers as the difference in radius between 320mm and 330mm diameter discs is 5mm.
You will find that by increasing to 330mm diameter discs, removing the caliper is more challenging as you have reduced the clearance between the caliper and the wheel rim. Andy
Personally I’d get a better quality 320mm disc myself, a thicker Brembo Serie Oro disc set rather than OEM. That made a bug different on my R1
Maybe just check your disc caliper bolts are long enough with the 5mm spacers fitted, there will be 5mm less thread into the fork bottoms. I'm personally not good enough on the brakes to NEED 330mm as opposed to 320 discs. Having said that, my 1299 brakes ARE the best on any bike I've ever used. I think that is more down to the suspension work from MCT.
So I finally got round to fitting the big brake conversion to my 899. The kit came from AR Racing which included longer bolts and 5mm spacers. The new brembo series oro replacement disc are 330mm wide and 5mm thick. I also changed the disc mounting bolts as well. Once fitted up and bedded in the braking force is night and day different. There is so much more feel to the front brakes and the the annoying low speed vibration has gone. I'm very impressed with this mod and would recommend it to anyone who feels like the discs are coming to the end of there life. The bike is showing just shy of twenty thousand miles now and I've owned it since six thousand. I've never tracked it just use it on the road but I'm surprised at how quick oe ones warped up. Is twenty thousand miles all that is expected from these ?
