binding rear brake

[jonno62]

Hi, my trophy 900, of 1993 vintage suffers from binding rear brakes, have had it apart and there appears to be no corrosion causing it, is there an alternative caliper available or could it be the master cylinder causing it? need to do something cos its discoloured the disc.

[Berniebikes]

My guess is the pins are corroded or dirty causing it not to slide. The rear caliper is sliding and needs to move back and forth a bit to align with the fixed rotor. Pull it apart and clean them thoroughly, or better yet, replace the pins with some stainless steel ones available from Sprint mfg.

[speed_triple_gav]

Could be that the pistons are stuck/seized as they have a habit of doing this. If you've not taken a look at MotT3's website have a gander coz it's really helpful with regards to this (and a lot more).

Gav

[jonno62]

Thanks, will check out the caliper pins, and pop out the pistons,are they honda items, they look familiar.

[MotT3]

It will be either pins or pistons..the seals get corrosion in the groove they sit in and it lifts them, eventually the outside seal starts to disintegrate and it's about then your caliper starts seizing..:-(

Take it easy with the pad pins they can round out if a bit worn..if so whack a torx bit in and see if they will shift if not it's drill time..!

Use red rubber grease on the pins as copper slip goes thick and gummy after a while.

I think it's a Nissin caliper so your right in thinking other models might be the same.

You can get seal kits here...http://www.triumphparts.gbr.cc/10442...earch=&sought=

Cheers
Mot

[Mossy21]

Try pushing the piston back into the caliper with fluid in the system and see if it moves. If not the return hole in the master cylinder is blocked.
Hope this helps.

[KitNYC]

I've had good luck polishing the pistons; haven't had to replace a set yet with three of these calipers across two bikes. Honda CBR600F2/F3 brakes are very, very similar Nissin units, but the Honda seals are just maybe a millimeter larger than the Triumph.

Cheers,
-Kit

[jonno62]

thanks for the advice, it looks like the torx drives on the end of the pins have been neatly rounded off, in fact only one pin on the bike is serviceable!, will have to drill them out in order to service the calipers, never liked torx fasteners, on the upside, there is loads of life left in the pads!

[Scarletfever]

Hope I'm not misinterpreting this but aren't the pad pins hex drive? I think MOT may have been saying if the hex has rounded try whacking a Torx bit in? Sorry if I've misunderstod, and you may have to drilll them anyway.

[zzwol]

I also had the problem with 3 rounded off pad-pin hex sockets. Hammered in a T40 torx bit and they all came out successfully.