hydrulic rear drum brake

[martinr]

im going to have another go at this setup i had a go about 2 years ago with limited sucess. ive got a homemade rear disc at the moment but im not happy with the runout on the disc .lammy rear hubs never seem to run true ill post some pics as i go

[Andy Pickering]

Excellent news Martin..

[martinr]

forgot what fecking nitemare it is

[camel]

hmm run out....i did one a few yrs back and i found the runout to be a big problem...i overcame this by machining the welded/bolted boss the holds the disc all running true on a lambretta layshaft in a lathe..that way the disc has to run true with the layshaft even if your hub is warped,clock up the layshaft....fit the hub cone and the hub,bolt into place and run between centres,then machine your dimensions,not sure id attempt another one after fiddling so much....but it did work!

[joee]

what about making the rear disc "float?"

[mark]

I just squared of my hub in a lathe on an old layshaft

[martinr]

im just getting mine done in a lathe. how much run out is acceptable just out of interest

[camel]

if your layshaft is running true in the lathe and between centres,and you hub bolted in place all your doing is mimicking it being on the bike so there really shudnt be any runout,i suppose you could get away with a couple of thou,but aim for zero,otherwise youll have the effect of a warped disc!
i had more trouble making a one off extended nut to run true to hold hub on and caliper in place