Caliper questions
 

I took my front calipers off today, for a complete overhaul, reaady for spring.

The right hand side came apart like a doddle - pin, pistons, everything just came apart like clockwork :)

The left hand side however...pistons are stuck. I've mangled them now anyway by being too hamfisted, there are pit marks all on the inside of the pistons. But try as I might my puny arms cannot muster enough strenth to get them out :(

I'd say they are about half way. They turn fine, just wont come out any further.

Needless to say, no access to an air compressor or anything like that.

Any tips? Dont care if its destructive to the pistons, I'll be getting new ones anyway.

Some other quick yes/no questions:

1. Can the piston seals be reused, if not damaged? I havent looked yet but if they are peanuts I will prob change them anyway.
2. Banjo washer - same as above
3. The two dust boots - as from the Haynes, it says: "Apply a smear of silicone based grease to the boots and fit them into their bores in the caliper. Is this a really bad way of saying to grease the pins the boots cover?

Caliper is swimming in a tub of Gunk at the moment, Halfrauds were out of Brake cleaner and said this would work also :o

Thanks

Re: Caliper questions
 

1. Can the piston seals be reused, if not damaged? I havent looked yet but if they are peanuts I will prob change them anyway.
2. Banjo washer - same as above
3. The two dust boots - as from the Haynes, it says: "Apply a smear of silicone based grease to the boots and fit them into their bores in the caliper. Is this a really bad way of saying to grease the pins the boots cover?

1: yes in most cases they can
2: should be replaced but i have just used the same one before
3:Yes lol

ohh and if the inside of the piston is scratched that doesn't matter its the out side that slides over the seals that matters, and when removing the pistons put a bit of 3in1 in the grove where the seal is and rotate them out dont just pull them straight out as its harder to do like that

HTH


PS clean the seals in warm soapy water then inspect, dont use brake cleaner it will dry them out, if you have a dish washer strip the calliper's down so there is no seals or any thing just the body and bung them in the washer with no tablet (or dishes) and wash away lol

should look nice a clean like these with no gunk in the bottoms of the bore

http://i357.photobucket.com/albums/o...2/P1040587.jpg

Re: Caliper questions
 

I'm no expert but maybe you could reconnect the caliper to the brake line and force the piston out hydraulically?

1. The seals can be reused if they're not damaged, but smear them with rubber grease before reinstalling. New ones are on wemoto, not sure on the exact price.
2. copper washers each side of the banjo? I would replace with new personally.
3. Copper grease the bolts, bleed nipples, retaining pins, maybe some rubber grease on the bleed nipple covers.

Re: Caliper questions
 

Cheers!

The outside of the pistons have a few marks as well :( I'd probably reuse them if it werent such a vital safety part ;)

I'll try some 3-in-1 overnight and try again tomorrow.

The other caliper is in Gunk now with seals in still...if I take them out now would they be ok to reuse?

No dishwasher, I'll have to do it the old fashioned way :(

Re: Caliper questions
 

Cheers Jordy.

The manual says to lube the seals with clean brake fluid...are you mistaken?

I cant use the hydraulics system on the bike (well I could, but its a bit too late now...) - I;d have to refit the whole lot and to be honest I'm too lazy. Its cold out :D

Copper banjo washers are like 20p so I will get new ones anyway.

They arent going back on til spring, so no real rush.

Re: Caliper questions
 

i use red rubber grease as well, but you can use brake fluid

Re: Caliper questions
 

Yeah mate from what I understand you just smear a small amount around the seals or in the recess grooves where they sit, also smear some on the sides of the pistons before reinstalling. This is information I've gathered from here, not from personal experience btw. http://forums.sv650.org/showthread.p...caliper&page=2

Re: Caliper questions
 

Main thing is to get the grooves where the seals fit really clean. They collect a 'whitish' deposit in there and stop the seals seating properly. I find a dentists plastic scraper , don't use metal ones!, are the best tool for the job.

Re: Caliper questions
 

i use fine wire wool for that job

Re: Caliper questions
 

Is copper grease the same as, or a suitable alternative to "rubber grease"?