KR-1S.co.uk Forum

Another alternative 310mm disc for zxr400 front end conversion is ZZR1100 D. Just bought a secondhand pair of prolites, they fit the 400 front wheel ok. Just need the 1.5mm offset to fit the fireblade calipers and grind a few mm of the inside of the calipers to clear the outer edge of the disc.

all 310mm discs (off the same era) will fit

first model ZXR750, I also thinck there is a ZX9 model, ZRX 1200 and probably some more ...

Ignore my previous post, discs are 320mm diameter, realised when pads sat too low on disc. Going to turn them down to 310mm.
I don't feel so clever now!

DAMO666 wrote:Ignore my previous post, discs are 320mm diameter, realised when pads sat too low on disc.

I tried them once and couldn't get the calipers on because off the discs beinig too big. How did you manage to get them on ?

DAMO666 wrote:Going to turn them down to 310mm.
I don't feel so clever now!

good luck

I thinck it will be cheaper to sell these and buy others than wasting your money on lathe tools

I split one caliper and bolted half onto the fork leg, then i scribed around the disc marking the inside of the caliper, then ground of caliper material upto said line. But now i will have too much clearance after i turn the disc diameter down to 310. I have access to a lathe so machining is free.Only thing is that 310 diameter will encroach into outer holes in disc, should be ok as long as there are no sharp corners to generate cracking.

brake discs are very hard, and very difficult to turn down

EBC prolites are ductile iron so somewhat easier to turn than stainless.