4ls gt550 to disk brake front end

[Ndulucky13]

I had a 4ls setup that I sold. It's on a 1972 gt550 I have now bought a 1973 gt550 disk brake rim and rotor with disk brake axke plus spacer and speedo drive. Will it bolt right up?

[Alan H]

No. You need a right fork leg so the disc caliper will have somewhere to go.
Back in 1973 when the disc brake was first fitted to the 550, they did an 'upgrade' to disc which consisted of complete right fork, wheel, pipework and master cylinder.
I bought one for my 550J and soon took it off as it was lethal in wet weather.
The 4LS is a much better brake on the 550.
If you get the disc(s?) drilled, that makes them a bit better.

[Ndulucky13]

I should have mentioned I'm going to make a custom bracket to hold a 6 pot tokico caliper off of a busa and a modern disk fitted instead of the original one. I do CNC machining for a living so I won't use the crap one pot with the original disk ha

[Alan H]

Be careful of over braking on one fork leg and twisting the forks.
Remember that the original discs are stainless steel and HAF. (Hard as f***!) And about as grippy as ice especially in the wet.