Z1OwnersClub GB

Stripped brake caliper on my Z1B for powder coating (piston seal leaking has stripped paint). Which way round does the new piston seal go, it appears to have a taper on the I/D to seal against the piston which I think lip should face the piston, but taking old one out it had lip facing pad side?

I'm fairly sure that despite the look of the seal, they are made parallel. The movement of the piston against the seal when you apply the brake "tilts" the seal to hold the pressure. I've just done my caliper and I know where you're coming from - my new seal seemed to be a bit biased to one side, so I fitted what looked to be the smaller diameter side facing inwards (towards the fluid) as you would fit a lip-type oil seal.
The little O rings fit in the two centre grooves of the slide bolts.

Thanks Jerry, havn't got new seal yet but will check it when it arrives and fit as you suggest.

Sorry to break up the party, but surely, I'd be tempted to fit the wedge, tighter bit againts piston, on fluid side
Hard to describe, but if it was a door wedge, the bit stuck under the door would be exposed to the air. Unless thats wot u meant

You Wally!! That's what I just said!

You have to excuse him! He gets a little confused when you use big words like diameter

I was going to suggest just leaving the caliper off, but thought that might sound a little harsh!

That's Ok,the rear brake is better than the front anyway

OK lads, I've got the message

It's back to the drawing board (or is it ironing board) for me

A reply worthy of our Mr Doran Jerry- LOL.
Ordered seal from Z power and Dave Marsden reckons they are parallel so don't matter which way round it goes. Pigfrod, I think you are saying the opposite to Jerry i.e larger dia on piston side is that true or am I picking it up wrong?

Just taken the old seal of my caliper, and it does seem to be angled
The new one also seems to have a slight angle on the inner face

Common sense would dictate that the thicker edge needs to be nearest the hydraulic fluid, if there is actually an angle

The main thing to remember John is to clean out the groove the seal sits in, if there is a build up of crud in there it will stop the piston returning properly.