P09 calipers

I’ve just started recommissioning a Spada which has been off the road for a few years. This is my first big block Tonti bike, so will be a learning curve to some extent. Next job is to sort the brakes. I’ve pulled the pads out and can see that the pistons are corroded, so I thought I’d order some new pistons and seals.
No problem for the front, but it seems that the big caliper on the back is pretty hard to get bits for - it seems to be variously called a P09 or F09 and has 48mm pistons. After some hunting around I’ve found pistons at TLM but nobody so far seems to have seals. Any ideas where else I can try?

As a backup plan, I thought about fitting a different caliper. The smaller front ones seem to have the same fixing centres. Has anyone tried swapping at the rear on a Spada? Should I ditch the proportioning valve?

I have also read about updating to later Brembo calipers. Again, anyone tried this?

Thanks, Ian.

Twin bleeds Ian ?..

Yes, twin bleed screws on rear.

Just sprayed it all with WD40 to see if I can get them apart before I order seals and pistons. New calipers seem to be available but more expensive. Having done a bit more digging I have found seals and pistons but may have to get from different places.

The P09 caloper is a massive improvement on braking over the P08 so stick with it if you can.
I got my bits from motoMecca but that was 10 years ago.

You could probably get Pistons made in stainless steel,try a local engineering company,or maybe shaws might

Pistons and seals are freely available-


I’ve done a bit of searching about and a couple of places do indeed have P9 parts, although not my usual first choice or second choice. Let’s see if they come apart first. Also need a front disc, and they seem quite hard to find. Nobody so far has any stock but I’ll keep looking.

They will come apart…


Once, I had to do three calipers where every piston was stuck. On one I had to drill and tap a hole in the piston then use a bolt as an extractor. Getting the bleed nipples out in one piece also provided unwanted entertainment.

I loosened all of the bleed nipples last night and also the capscrews holding the halves together, so I am happy to order parts now. Pistons move in both the front ones so hopefully will come out. Also tried swapping front and rear just to see - P08 fits on rear with no issues, but P09 does not quite fit on front. Bridge of caliper hits disc before bolt holes are lined up but I think Guzziology explains how to sort this out. I am going to stick with what I have I think.
Anyone know anything about DOT5 silicone fluid? Front has DOT 5 in (although it’s all drained out now) but rear had normal brake fluid. I’m sure I read somewhere that once DOT5 has been used you should stick to it, although OK to swap from normal to DOT 5.

Sorry a bit late with this. But Gutsibits have the seals and pistons for p09s. Did mine end of last year.

Got seals and pistons from HMB in the end. Haven’t got round to doing the calipers yet, been painting bits and pieces, plus trimming the hedge, car MOT etc…

Got all the calipers apart without too much difficulty and should get them rebuilt over the weekend. Unfortunately broke the seized bleed nipple off the proportioning valve in spite of soaking in WD40 for a few days. Couldn’t get it out so ended up dismantling the valve so I could drill through and retap. Hopefully can get a short screw to seal with a copper washer. Valve looks OK inside.