brake problem

[joel armstrong]

i am from a 6th form engineering team, we are currently building a three wheel kitcar with a motobike as the rear wheel and power source.

we have disk brakes at the front from a vauxhall astra but the kawasaki gt550uses a mechanical drum brake. for us to pass the MSVA the two much work in unison.

is it possible to connect the drum brake of the bike to the disc brakes of the front and get them working fully and hydraulicly? if so how?

any help will be greatly appreciated. cheers.

[woodsmith]

One option would be to find a disc braked version of the bike and swap the approprate parts.

The other way could be to remove the lever on the drum brake and turn it 180 deg so it is a push instead of pull. Then use a clutch slave cylinder mounted to the swing arm close to the brake and fit a stiff push rod.
You could extend the lever both ways so that the push is hydraulic but retains a pull for the handbrake.

I've no idea how IVA/MOT or generally safe this would be though.

I had this consideration when designing my trike.
I had a Yamaha Dragstar rear wheel as a starting point and it needed a swing arm with shaft and drum brake. It got complicated but I figured that I could use it as a parking brake anyway.


In the end I found a Honda VFR750 swingarm with disc brake. It saved the drum brake issue but introduced the hand brake issue meaning that I need to buy a mechanical caliper and adapt to fit.


I am now scratch building the swing arm to get the pivot concentric with the motor shaft to retain chain tension.