Topic: Caliper and Fork Compatibility (CB750)??

[nickbee]

Will a Caliper from a K2 work with a Fork from a K4/K5?  I’m gathering parts for a café café racer and just want to check on compatibility. 

Was there a difference in the calipers over the years?  Any preference I should have if I’m starting from scratch?   


Thanks!

[Clyde]

The same caliper was used from K0 to K6. But the hanger/arm that the caliper bolts to ,was changed from the K3 on.
This means the lower fork legs and front fender mounting points are different.
A different caliper was used for the F/F1/K7/K8. The F1 caliper and arm can be used on the K3 to K6 fork legs, but you must use both together. The F1 caliper cannot be used with either a K0-K2 arm or a K3-K6 arm.
If I was starting from scratch and using a single disc, I would use an F1 caliper/arm on the K4/5 fork as they have a bigger piston diameter and you get a bit more mechanical advantage. If you are using dual discs, probably does not matter too much in my opinion
As Terry would say use an F2 front end and get really good brakes

[laminarflowone]

Not to revive zombie threads, but does that mean I could use a K7 caliper and mount on my K6?  Or is it better to bet a K3 caliper and buy the K6 mount?

[754]

K7 caliper and mount will fit on but looks different..no fins & more. So it works, but you would not want to add it as a second caliper on a stock K6 fork.

[laminarflowone]

Thanks, so that would be the same for '78 calipers?  I'm not running dual setup, I just want to have a front brake because mine was missing when I got it from the PO.

[754]

77/78K calipers are the same
 78 Master cylinder though, had brake switch as part of it, as opposed to on lower tree.