Rear brake pistons

[Triplespeed]

Haing a few hours at last to devote to the ongoing project I tried to remove the rear caliper pistons but alas they were seized so in a bit of a mad moment I got the pipe grips out and with a bit of persistence they are both out.

My persistence also led to some marking on the pistons - i did this on a car and there was no marking so im assuming these pistons are a tad softer.

My question is how much marking can I get away with before they are considered unfit for purpose? I realised I have been a bit of a plum but its all a good learning curve.

If I need new ones I assume theyre around the £30 -£40 mark but where from?

Thanks all

[Drunkn Munky]

There most likely scrap mate, rick oliver sells a pattern kit piston inc seals fairly cheaply

[Triplespeed]

There most likely scrap mate, rick oliver sells a pattern kit piston inc seals fairly cheaply

Thats what I thought, oh well. I'll add it to the list

Thanks for your help - always nice to have a second opinion

[speedy231278]

You'll want a decent tool for scraping the crap out the grooves when you take the old seals out. Mine were minging. I'd order a new bleed nipple, the old one is probably scrap. Every time I do a caliper I put a new one on, with a rubber boot, but the hex part always seems to corrode and chew up when the time comes to slacken it!

For £15 you can get Sealey piston pliers which work on the inside of the piston so any marking won't affect the seals. Even with those, one of mine was still a complete bastard to get out...

[Neosophist]

If there marked then id junk them.

If the marking rubs on the seals it will either leak or trash the seal or collect dust and shit to corrode away.

http://www.wemoto.com/bikes/honda/vfr_4 ... ope/90-91/

Wemoto sells rear pistons, 27 quid each in stainless steel with the seals too, you obv need two.

So for around 50 quid you should be good for another 25 years or so providing you clean it occasionally.

You can also try Rick O (id recommend him first)

Dave Silvers / Lings / Honda dealer should be able to order you them up too.

Dave silvers has some pattern pistons in at 18 quid each (no idea what they are made of, so 36 quid for the pair), their seals are genuine honda and is 14 quid, so I assume thats for both pistons)

either way around 50 quid.

just make sure when you remove the old seals to clean any corrosions and shit from the groves i scrape them out gently then brass brush them, and always, always remember to fully lube up your piston before slowly inserting. (read into that as you see fit, im sure its a brake caliper guide)

[Triplespeed]

thank you for the advice on clearing out the caliper and the piston pliers. I`m slowly building up a better supply of bike tools as I can get a trade discount from Halfords but that sometimes amounts to 0%
I was looking at Wemoto for a whole host of consumables such as the bleed nipple and the various rubbers on the caliper, exhaust gaskets and clamps with a few other rubber bits and pieces - I`ll also check out Rick to see how the prices compare but I was swayed by stainless pistons.
I have ordered some red castrol grease for the caliper so my shafts should be nice and slippery oooer.

Once again thank you very much guys, the projects looking like hitting the road when i can get all these little bits sorted out.

[speedy231278]

Ah, you have a Halfrauds card. Grease and oil are cheaper, but Swarfega gets no discount! What confised me is that I bought two different torque wrenches, both were £75, however one reduced by £30 and the other by £20....

As for the DSS pattern pistons, I don't know what they are made of either, but I can tell you they do the job!

[Triplespeed]

The only thing I could spot with dss spares was the price. The piston price is not inclusive of seals so I'll go with a couple of stainless pistons. Will just have to get them shot blasted then rebuild