brake caliper piston seals

[exchead]

hi can someone on here tell me which way round the brake piston seals go in to caliper on a 2005 Girly,have removed old ones with a pick and have new ones ready to go in,the new seals have a taper am i right in thinking the smaller end goes in to caliper,is it best to use red grease in seal gap and brake fluid on piston to help ease them in

[PeteH]

Best I can think of would be the thinner bit to the outside so allowing the pistons to be inserted easier (best of luck there) cant see any problems using rubber grease...I just used a smear of brake fluid when I rebuilt mine.

[exchead]

Best I can think of would be the thinner bit to the outside so allowing the pistons to be inserted easier (best of luck there) cant see any problems using rubber grease...I just used a smear of brake fluid when I rebuilt mine.

yes thats what i think but the ones i took out the wider side was on the outside,haynes book shows a pic of seals fitted wider side to outside too but haynes have been known to be wrong,having said that the calipers never leaked only changing cos of salt damage where seals sit making pistons tight

[PeteH]

Hmm, you could always contact the place you bought them from to confirm fitment or just go for it, I notice from the pics on Triumph Online that the 955 also have a dust seal ?
Thought some 955 guys might have helped out here ??

Best of luck and keep us posted on any progress...

[Bixxer Bob]

Not jumped in here because it's ages since I had one apart and I can't remember.

[Sin_Tiger]

Not worked with these calipers before, buuut. Standard on most calipers is with the open end of the V on the pressure side i.e. "thinner" side out. reason is that when pressure is applied it will tend to force the seal against the sealing surface of the piston.

Were you not able to tell which way round they were when you took them out, they must have been in seriously bad shape.

[daveb]

I got my old set of front calipers from the 955i completely stripped down at the moment,  there are 2 seal per piston on the 955i a thinner one for the dust seal (pad side) and the thicker one for the main seal.

I will post some photos later if required, as I got the piston out.

[exchead]

tookthe other caliper apart today and made a note which way round the seals went in and it seems that the haynes manual is correct the bigger part of the seal faces outwards so the bevel goes inwards gods knows how they dont leak this way round,most other bike calipers i have rebuilt ie honda ones and ktm haveflat round seals with no bevel

[Mr_J]

I changed the seals on my tiger last week and fitted them with the bevel on the inside. The pistons were a bugger to get back in, but there's been no sign of leaking so far. Hope this helps!

[exchead]

I changed the seals on my tiger last week and fitted them with the bevel on the inside. The pistons were a bugger to get back in, but there's been no sign of leaking so far. Hope this helps!

many thanks that puts my mind at rest

[NortonCharlie]

I believe the reason they seemingly go in backwards is that when the pressure is released and the rubber relaxes it pulls the piston back slightly into the caliper.

[Sin_Tiger]

I believe the reason they seemingly go in backwards is that when the pressure is released and the rubber relaxes it pulls the piston back slightly into the caliper.

That's unlike any other caliper, hyd ram, motor or shuttle valve I have rebuilt, first time for everything I suppose. The piston will return slightly when pressure is released regardless.

[blacktiger]

My WS manual says nothing about which way round the seals go in as if they don't/shouldn't have a taper. As it's several years since I did mine I can't remember either. Is your seal kit from Triumph or an after market source?

[Bixxer Bob]

Been pondering this.  I can't be certain, but my OEM seals when I did them last spring, were - I think - straight.  I didn't notice any taper.  They work ok.

[exchead]

oem are tapered haynes manual shows tapered,some pattern ones are not but still fit and dont leak