Brake disc swap CB550F ---> CB750 K7

[notobikeparkingtax]

Anyone know if this is a straight swap ? I've sent my K7's disc off to Len Cooper to have a cast iron disc fitted and it's already a week overdue with no sign of it being done. I want to ride my flipping bike!!
 I can get hold of one off a CB550F, part numbers are different but I'm not sure if that means it wouldn't fit at all or that the carrier is painted a different colour!

Thanks in advance,..

[Bryanj]

Smaller diameter so it wont work sorry

[notobikeparkingtax]

Cheers Bryan, saved me a bit of grief that has !

[Yoshi823]

If you utilised the 550 caliper bracket then you could use the 550 disc.

[notobikeparkingtax]

Thanks Yoshi823,, worth knowing.

Having been told by Len Cooper engineering that the brake conversion would be done in 3 weeks, my brake disc should actually be back with me next week...maybe. That'd be nearly 2 months after it was received by them.

Seriously..not a happy bunny right now. If it was going to take two months I'd have appreciated being told that at the beginning.

[Bryanj]

Back in the late 70's there was a firm that did cast rotors to bolt onto the standard carrier and i got one for my 500 four, i found that it made no difference in the dry and in the wet the brake worked and locked up sliding the front wheel out from under me!!!

I eventualy went to twin standard discs with one caliper in front and one behind (this was before the 550 came out with mirrir image sliders) plus a Goldwing master, that made the tyre howl when braking but never locked on me

[Yoshi823]

I remember that advert being in 'Bike' magazine & possibly in 'Superbike' mag. It seemed like a good idea at the time, particularly because the brake pads of there day were not that good...until Ferodo brought out a worthwhile compound.

There's a forumite on here that has a CB750K sohc with a 500/550 front disc on it...the 750 is quite a lot bigger & it was this that I noticed.

[matthewmosse]

Pfm I think do cast disks to replace stainless on Bmw's so that's where I'd look for cast disks. I deffinately think they have their place if you tend to use the bike in all weathers, though I just drag the front brake on almost pernemently if I get caught in a real downpour on the 500/4, onece warm the standard rotor works fine even in the worst Welsh / Yorkshire downpours, particuarly bearing in mind the tyres get less grip in those conditions and when I onece was on the motorway from Leeds in such conditions visabilit was also down to nil too. Brakes in standard form were still good for hauling a bike, sidecar and spare bike in bits and tools to put spare bike in bits all to a halt at motoway speeds - reduced speeds for conditions as I like to be able to stop on the amount of road I can see!