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View Full Version : Front disc brake, grabs disc too much



accel_unlimited
15th July 2007, 13:56
hi, i have a 1994 suzuki sepia zz 333 50cc and the pads( dont know what they called) are rubbing/grabbing on the disc to much without squezing the lever is there any obvious way i could fix this at home? or does something need replacing? :scooter: :scooter: :scooter:

JimO
15th July 2007, 15:19
hi, i have a 1994 suzuki sepia zz 333 50cc and the pads( dont know what they called) are rubbing/grabbing on the disc to much without squezing the lever is there any obvious way i could fix this at home? or does something need replacing? :scooter: :scooter: :scooter:
the disc may be warped and need skimming or replacing

FROSTY
15th July 2007, 18:29
I think the sepia has drumbrakes. You just adjust the adjuster cable back a turn

Tim 39
15th July 2007, 21:13
I think the sepia has drumbrakes. You just adjust the adjuster cable back a turn

I'm sure in the title he stated that it has a disc brake!

Tim 39
15th July 2007, 21:17
Oh and to answer the problem...it sounds to me like you need to take the caliper off, the pads out and clean the caliper piston/s (pump them out but not right out). When theyre clean (use metal polish to polish them) then rub a bit of brake fluid around them to lubricate. Push them back in and put pads etc back in and this should solve the problem. If that doesnt help check to make sure the handle isnt being held in or anything silly like that

xwhatsit
15th July 2007, 21:56
I'm sure in the title he stated that it has a disc brake!

<hints id="hah_hints"></hints>Just did a quick Google Image search and they certainly do seem to have drum brakes, and the fact that he doesn't know whether they're called pads or not may mean he's made a mistake. Apologies, accel_unlimited, if they are actually discs.

If they turn out to be drums, and if the linkage is anything like my rear brake, the adjuster on the linkage may be tightened up too much. If it's possible to back the cable off so there's more free play in the lever, that might be worth a shot. But as Ixion pointed out, drum brakes are largely a black art to me, so is there a more common cause of this?

accel_unlimited
18th July 2007, 21:23
Dude, the brake im worrying about is definitaly a disc. its because this version is a bit better than the standard sepia

imdying
18th July 2007, 23:02
How long have you owned it? Are the pads in good nick? Have you serviced the caliper? It's probably a single pot sliding caliper on something that small, so if the slides are gunked up and dragging, it'll drag the pad on the disc. They use square section orings for the shear effect, so if the piston that it works on is covered in crap (typical for bikes, they haven't got the piston boot common cars) it'll drag the piston and thus the pad too. If you can spin the wheel and it only drags in particular places, then the disc might be suspect. If the master cylinder lever to piston clearance is a few thou at least at rest, it'll potentially hold a small line pressure which'll make the caliper piston drag, and thus the pads. Potentially the compensating port (which if you look where the output of reservoir is, it's one of the two ports you'll see) could be blocked, which would cause a small line pressure in the output of the master cylinder, and thus the piston and pad would drag. It is even conceivable that the hose could have a tear on the inner tube, which creates a flap, which holds line pressure, causing the piston and pad to drag.

We're getting progressively more and more unlikely though, so start at the top and work your way down.