brakes wont release (bandit) ?? please help

[gorgeous george]

hi this is my first post lads,,,, so hi everyone i have a 97 600 bandit ...

i took my front wheel off before Christmas to paint but have had to put it back on before ive finished because ive been kicked out of my dads house, so i have to move the bike so i was putting the brakes calipers back onto the discs after having them properly hung on bike with a bungee cord so the brakes didnt dangle down on there own brake lines.

but to get them on the discs i had to prize the pads apart another few mm to get them on the discs.... when they were fitted o pulled the brake lever in and it was as if there was no brake, so pumped it a bit and then i could start to feel like it was working but then i noticed the pads weren't releasing and now there locked on the discs ???

please help i havent a clue what todo

thank you

[Kickstart]

Hi

The calipers are sticking. Either the pistons themselves or the pins they slide on. Given that you got the pistons to retract my first guess would be the sliding pins.

All the best

Keith
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[shugsterc]

take calipers off unscrew fluid rezz take pads out use a g clamp or stilsons to push piston into caliper..use brake lever to push back out..wd40 clean the piston the grease it push in an out a few times till it feels freeer put back to gether and it be grand...just a bit sticky

[gorgeous george]

[gorgeous george]

[gorgeous george]

[bridlad]

when youve removed the pads and cleaned the sliding pin make sure you put a flat bar or piece of wood between the pistons when you use the lever to push them out ,you dont want any of the pistons popping out ,once youve got them so far out use clean brake fluid and a tooth brush to clean the pistons dont use wd40 ,dont be tempted to use anything abrasive on them otherwise you will scratch them then they will leak,when you are satisfied they are all moving freely push them right back into the caliper ,apply some copperslip grease to the sliding pin and the ends of the pads which slide in the caliper dont get any on the friction material of the pads for obvious reasons ,refit the calipers pump the lever a couple of times until it bites and job done ,hth

[Kickstart]

Hi

If it is the pistons (personally, unlikely the main problem) then you use a rubber grease (normally red) on the sides of the pistons. Make sure you don't get any on the friction surfaces of the pads.

With sliding calipers like the 600 Bandit, you have plenty of room to push the pistons back with a G clamp. Also When pushing the pistons back on one caliper make sure the other has the pistons secured to stop them popping out (generally it is easier to push the other pistons out than it is to push the fluid back into the reservoir).

For the pins, take a caliper off, remove the pads and then slide the caliper off its carrier. Clean up the pins and reassemble with a suitable lube

All the best

Keith
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[bagger]

i wouldnt bother with wd40 on the pistons just use clean brake fluid and a toothbrush
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sv650s,cb350s

[jj49]

hi there, i had the same problem as you and have suffered with dragging brakes and a wooden feel for months, so i purchased another set from a breakers to refurbish and swop over on the bike, a 98 bandit 600sw.
you can spray the pistons (once pads removed) with silicone spray this wont damage the seals and could help in unsticking them . If you need to clean any corrosion off use a green pan scrubber this wont cause any scratches etc. Then with a small g clamp gently screw them back , make sue you use a cloth over the piston ends and caliper to stop any damage and unscrew resevior top, as in your case they are still fitted ( hydraulic pressure).
you will find as i did and others often complain about is the caliper slide pins stick and wont budge if corroded. heat has to be applied and a leather/rubber mallet used to pursuade the caliper bracket to slide off . I entrusted this job to my local bike shop in the end, who blew the pistons out, fitted new seals and rubber red greased the sliding pins and piston ends.
try and pull the bracket /slider pins away from the caliper, becareful not to damage the rubber boots, the bracket is suppose to slide off. if they are jammed solid then it will be a garage job or vice and heat/mallet and a good squirt of silicone spray.
if you are succesful your local bike shop should have satchets of red rubber grease which is silicone based to be applied to the slider pins once cleaned up.

[gorgeous george]

gonna give this ago with my haynes manual welded to my hand because im feeling pretty baffled with what todo

[bridlad]

Red rubber grease is great when reassembling calipers after fitting new seals etc but isnt that good on the sliding pins they really need to be coated in a high temp anti seizure grease (as should all steel bolts into alloy )i.e copperslip it stops the chemical reaction between the steel threads on the pin and the alloy caliper which causes them to seize also wont melt and find its way onto your pads if you really are bothered about doing it watch some vids on youtube

[Kickstart]

[Pol Anorl]

This happened on my bros last week, i ended up with a crow bar on my caliper to get the pistons back in, pumping to get them back out and repeating atleast 10 times to losen them up, now one side is stuck in so i have a lose brake pad that just taps like fuck at <30mph

Pistons are damn expensive! i got a 4 pot caliper the pistons are about £25 each x 4 = £100 not good.

my first thought was to brake untill 1 piston came out, clean it up little bit of fine paper then put it back in and repeat, but bleeding the brakes over and over again seemed like a pain in the ass so it was literaly a case of getting one side out cleaning up then swapping to next side then repeat untill its smoother, mines just fucked and i cba to mess about so going to purchase a new caliper soon.
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[bridlad]

[Kickstart]

[bridlad]

AAh I see now we are talking mounting pins,I stand corrected This might help the op if he can see how its made up

[gorgeous george]

if i follow this guide will i un-stick me brakes ??

i also asked a bike mechanics how much for them to change the piston seals and fix the brake he said 45 each caliper ?? is this reasonable or not ?

[Kickstart]

Hi

£45 a caliper isn't bad (although adds up). Looking at Wemot the seals are £5 per piston (for pattern ones), so £20 of seals and say £10 for brake fluid. He is charging you £60 for labour which is well within reason for what can easily be a couple of hours work.

That said, being twin piston sliding calipers they are quite easy to strip and clean yourself:-

Remove a caliper.
Remove the pads from the caliper.
Pump out the pistons. Make sure they both come out at the same time (if necessary use and old brake pad and a G clamp to stop one piston coming out while the other catches up). If you are careful one will pop out and the other will be almost out and easily removed with your fingers. Fluid will go everywhere (one trick is to put the caliper in a plastic bag to catch the fluid as the pistons come out).
Hoik the seals out.
Clean up in the grooves the seals live in (there will be a load of white alloy oxide in there) but be careful not to scratch the actual alloy.
Soak the new seals in fresh brake fluid.
Clean up the pistons carefully.
Put the new seals in place. Make sure they are not twisted and are seated correctly.
Put some fresh brake fluid on the pistons and push them into place, making sure you push them in straight. They should go in reasonably easily.
Put the pads in and put the caliper back on the bike.
Bleed the brakes quickly (don't need to be perfect at this stage, just enough to pump the other pistons out) and repeat the above for the other caliper.
Then bleed the brakes properly.

This is easy on these sliding calipers.

The difficult bit is that the caliper slide on a pair of pins (there is a carrier that bolts to the fork, and the pins are part of that). If they are not sticking then they are easy, but if sticking they can be a pain to remove (plenty of bodgit ways such as levering against the disk or fork leg, but then you stand a good chance of damaging whatever you are levering against).

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[gorgeous george]

thanks i think im going to it a go cheers for the help boys

[Fizzer Thou]

Brakes that started out this rotten

https://i666.photobucket.com/albums/vv23/WiNot_Rhencullen/Workshop/Picture383.jpg

Soon polished up and cleaned up like this

https://i666.photobucket.com/albums/vv23/WiNot_Rhencullen/Workshop/Picture384.jpg

The main area to clean is where the piston seals seat.Crud builds up in these ring lands and with careful cleaning will allow the seals to no longer push against the pistons when they should be allowing them to pull away from the brake pads.
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