Brake Calliper Rebuild

[harpmeister]

I've never had the pleasure of having to rebuild my P 09 callipers, up to now that is. I don't foresee any problems but I just wanted to run it past the more experienced among you.

The callipers are not apart yet so I don't know what the condition of the piston is like but assuming that everything is okay I was just planning to thoroughly clean everything use a smear of red grease on the o ring, piston seal, the side of the piston and pack the dust seal with it and put it all back together again.

Does this sound okay or is there anything else I should be aware of.

Joe

 

[mauricejota7604]

Be prepared to replace the pistons if they are old steel ones do you have 09 Calipers or do you mean 08?
Regardless unless you are really lucky and the pistons are not rust pitted replace the seal and dust covers they are sold as a kit square o rings o ring that seals the caliper halves dust covers and allen bolts a small sachet of rubber grease is also provided.
You may have to use the hydraulic pressure to force the pistons out.

 

[GPR1200]

Maurice, have you sold up? ;o)

81 Jota*7604* (Old Faithfull
83 RGS project bike*1675*

 

[2622]

Maurice, have you sold up? ;o)

81 Jota*7604* (Old Faithfull
83 RGS project bike*1675*

Sold up ??? think you mean buying up and is just trying to hide all the bikes from Deb, now she has told him to sell a certain green bike to someone but does he listen no..... he dont.

Oh Joe whilst you have the calipers apart and sometimes it can be a pain to remove the two M8 bolts which hold them together so some rostoff or similar before hand helps ... oh and to get the pistons out you need some compressed air and keep your hands clear... as per Maurice dont even think about reusing the metal pistons.. get the pukker new style ones ... and not too much red grease on the pistons then start them square and gently pull them in closing your fingers and whilst the palms are at the rear, they should slide in without too much effort. Then make sure that the dust seals are home all around then on assembly and make sure you put the small flat oring between the two bodies and tighten the bolts up to the correct torque.

 

[Dellortoman]

G'day Joe

By P09 do you actually mean F08?

The correct designation is either P2 F09 or P2 F08.

Laverdas were originally fitted with F08. If yours has F09 calioers, they must have fitted by a previous owner.
They were original equipment on some Guzzis and Benellis, so rebuild kits are available.

You need to be sure what you have before you order the rebuild kits. It's easy to check. 09 calipers have 48mm dia pistons, whereas 08 calipers have 38mm dia pistons. You can tell by looking at the outside of the caliper. The F09 cylinder area is bigger than the 08. See photos below.

Cheers,
Cam

 

[Davo]

Oh Joe whilst you have the calipers apart and sometimes it can be a pain to remove the two M8 bolts which hold them together so some rostoff or similar before hand helps

I made up a mounting plate out of 75mm x 75mm x 10mm angle iron, bolted it to a railway sleeper and fixed the caliper to it so that I could get enough torque through the M8 bolts to get the things apart despite all the penetrating fluid and heat applied.

. oh and to get the pistons out you need some compressed air and keep your hands clear...

The pistons in mine were so badly stuck I ended up using copious heat and burning out the rubber seals and only then did the pistons come out. 

 

[Vince]

Years ago I couldn't budge the pistons on a Parallel twin Ducati, the local brake place used a grease gun.

 

[drikko]

New calipers complete with pads arent that expensive. On reflection I sbould have gone that way with the 900SS. The pistons were totally corroded in. One of them did come out reasonably easily and I noticed there was a gap between the piston and the side of the caliper so I carefully drilled and tappes an 8mm hole in the middle of the piston screwed a bolt in and screwed the piston out quite easily. I was worried it might punch a hole through the caliper but it was fine. Cleaned the calipers up, new seals and pistons and all working fine.

 

[2622]

I made up a mounting plate out of 75mm x 75mm x 10mm angle iron, bolted it to a

The pistons in mine were so badly stuck I ended up using copious heat and burning out the rubber seals and only then did the pistons come out. 

Hey Davo another option is if they are that stuck is to well a nut in the centre of the cup and then use a puller to drag them out. But when stuck that badly always a very good idea to carefully check the bore as the rust/electrolosis can damage it.

 

[Davo]

Bores were fine. Shouldn't make any difference anyway unless really severe as the pistons move on the seals.