[jaguar]

im putting a 78 front end and wheel on my 76F
as far as i know it sould just bolt on. using everything off of the 78 to give me duel disks.
im thinking later down the line but does anyone have info on brake upgrades? ive read alittle about the later DOHC CBs twin disks. ive also seen CBR900RR and RC51 brakes that look like they can be made to work. is it a simple matter of and adaptor plate or more involved?(im sure it is). when you change to different calipers can you use the stock discs?
any help and info would be great


There is the right way, the wrong way and the british way to do anything!

 

[Geeto67]

you can use the 1982 cb750F/900F dual pot calipers on the earlier forks, you have to use the 1982 brackets to mount them to the brake legs but otherwise it is a bolt on affair.

Outside of that I don't know what else except doing a cbr wheel swap. The cbr f2/f3 front wheels can be made to fit the front end on the DOHC bikes pretty easily so there is a chance they will work on the 78 SOHC front.

for the rear I think you are stuck with the 76 rear caliper as long as you have that rear wheel assembly.

You could narrow and swap in a DOHC rear swingarm (the 79 arms don't need narrowing but the 80-83 do) from a 900F and that would give you the 900F's brakes and also the ability to swap to an 1100F rear wheel to run a fatter tire in the rear but I have no idea if the chain line lines up. This is all therotical, I have not done this swap but I think it is possibly based upon my familarity with the components involved.

I have to ask though, why are you so concerned with dual discs? If you lighten the cb750 (in they way I think you are going to do) the bike does stop fairly well. I ride my 75K with stock single disc into the city everyday and it still does one hell of a job.

 

[jaguar]

to be honest about the duel discs it is just a newbe mistake about looks over real performance. if one is good two is better?

i but the rear wheel off the 78 on the bike and it seems to fit perfect.

i keep seeing mid 80s CB1000/900 twin pot calipers chaep and thought that it might work well on the bike. and if im understanding right sould bolt on fairly easy?

have you ever done or seen someone use modern brakes like brembos on a vintage wheel?


There is the right way, the wrong way and the british way to do anything!

 

[Geeto67]

quote:
to be honest about the duel discs it is just a newbe mistake about looks over real performance. if one is good two is better?

i but the rear wheel off the 78 on the bike and it seems to fit perfect.

i keep seeing mid 80s CB1000/900 twin pot calipers chaep and thought that it might work well on the bike. and if im understanding right sould bolt on fairly easy?

have you ever done or seen someone use modern brakes like brembos on a vintage wheel?


There is the right way, the wrong way and the british way to do anything!

The closest thing I have seen to modern brakes on a vintage wheel are the ex500 calipers they use on the kawi triples. The problem with modern brakes is the disc thickness. modern rotors are much thinner than the old rotors are and the calipers don't fit the old rotors. When they put ex500 (zx6R calipers also) on a kawi triple they have to either turn the rotor down to 5mm thickness or use a kz650 rotor which is the same bolt pattern as an h1 wheel and 5mm in thickness. I forget how thick a cb750 disc is but it is much thicker than 5mm and it is also stainless steel which means you can't really turn it down safely.

I have an old grimeca setup for a cb750 and it looks pretty heavy duty but it came with its own rotor.

the 1982 twin piston cb750f and 900F calipers are the ones you want, and you have to get the brackets for the fork legs for it to be a bolt on deal. I think that tokiko design was still in use (adapted to other bikes) through the 1990s so for all intensive purposes they are "modern brakes".

 

[n/a]

quote:


have you ever done or seen someone use modern brakes like brembos on a vintage wheel?

Newer sportbike brakes on CB 750K wheels(brembo 320 mm fr discs, tokico calipers)
DG
Cut and paste

http://i111.photobucket.com/albums/n130/dgfischer/FRWheel.jpg



Edited by - dgfischer on Sep 05 2007 08:22:21 AM

Edited by - dgfischer on Sep 05 2007 08:23:42 AM