Page 1 of 1

Rear Brake Help Please

PostPosted: Tue Apr 05, 2016 6:36 pm
by devlam
I wonder whether any of you can help with this please. Prepping for MOT on new build. New rear hub and shoes cables etc. I'm struggling to get good adjustment on the new set up. I had to fix the rear brake arm quite a way forward before doing up pedal clamp to get anywhere close to reasonable adjustment, but I find now that the brake arm seems to be sticking on. It's not related to the cable as when I release the pedal there is play in the cable. If I push the arm back it seems to click free. I'll take a look tomorrow but if anyone has any thoughts I'd be much obliged.

Cheers, Mark.

Re: Rear Brake Help Please

PostPosted: Tue Apr 05, 2016 6:40 pm
by Tony Hart
Hi. Sounds like the brake-cam is going over centre. Do you have the correct brake shoes fitted - the GP and LI ones are different to work with the different brake cams

Tony

Re: Rear Brake Help Please

PostPosted: Tue Apr 05, 2016 7:40 pm
by Granty
I had this same problem, it was the brake cam moving to far to engage the brake and jamming on, when I released it there was too much play in the cable,tightened the cable pedal end and greased the cam where it engaged with the brake pads,lightly mind on the grease, no probs again,G

Re: Rear Brake Help Please

PostPosted: Tue Apr 05, 2016 7:56 pm
by devlam
Thanks for that -- It's a new uni hub, the shoes are Li and the Brake Cam is the original Li. Based on your suggestions I guess also that the cam could be worn then. Will look tomorrow. Thanks.

Re: Rear Brake Help Please

PostPosted: Tue Apr 05, 2016 10:42 pm
by Norfolk
On my scoot there is a thin clip that fits around the brake cam onto which the brake shoes rest, in effect making the cam larger and enabling the brake shoes to fit closer to the brake drum. In my opinion it is too good a fit to be a bodge that someone fitted in the past

Norfolk

Re: Rear Brake Help Please

PostPosted: Tue Apr 05, 2016 11:04 pm
by Knowledge
Isn't there something about ensuring the cam is the right way round? I think there is a punched indent on the cam which shows which way round it should be (indent facing up?)

Re: Rear Brake Help Please

PostPosted: Wed Apr 06, 2016 7:42 am
by CHRIS in MARGATE
Norfolk....that's probably GP set up.

Re: Rear Brake Help Please

PostPosted: Wed Apr 06, 2016 10:19 pm
by Norfolk
Sorry, Chris in Margate,

1964, Li series 3,

Norfolk

Re: Rear Brake Help Please

PostPosted: Wed Apr 06, 2016 10:27 pm
by CHRIS in MARGATE
OK with LI cam and brake shoes ?

Re: Rear Brake Help Please

PostPosted: Wed Apr 06, 2016 11:11 pm
by Norfolk
To the best of my knowledge :roll: i have only changed the shoes, the cam and clip are original, well since I brought the scoot in 1978 for £35.

Norfolk

Re: Rear Brake Help Please

PostPosted: Thu Apr 07, 2016 5:27 pm
by Wack
One to watch is the cam hole isn't worn oval in the casing.

Re: Rear Brake Help Please

PostPosted: Thu Apr 07, 2016 6:08 pm
by devlam
So I've taken it apart and the cam is definitely hanging up on the corner - tried a bit of grease but still no good. I'm going to try replacing with a GP cam and shoes.

Re: Rear Brake Help Please

PostPosted: Thu Apr 07, 2016 7:42 pm
by MK Monty
Have you still got plenty of meat on the shoes. New shoes are normally a tight fit getting the hub on. If they are worn you can go past the cam point of return.

Re: Rear Brake Help Please

PostPosted: Fri Apr 08, 2016 6:58 pm
by devlam
Changing to GP shows and cam seems to have fixed it. I think the Li shoes were possibly not best quality - cam seems to have indented the contact point on the shoe and I think this is where it was sticking. I still don't have wonderful stopping power but will let them bed in and adjust. Thanks for the hints.