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a little help with my brakes.

Thu Sep 11, 2008 6:14 pm

hey guys,
I own a zxr250 and i took of the brake caliper to chnage the pads, but my disc is far to damaged so i have to replace that to. i took of the caliper and took of the pads but i sort of got the piston closed, i opened up whatever i could, but i cant get the old pads back in let alone the new ones.

I snapped 2 G clamps trying to push it back in. i had the brake fliud cap opened so it can pushed back in easier but it wont budge.

any ideas on how i can push it bakc in to put my new pads in?

(sorry bout pic quality, took it with my phone) :?

i put 2 pictures in, one is with one pad and the gap between the pad and the piston,
.
Image024 (2).jpg
Image024 (2).jpg (223.49 KiB) Viewed 2093 times


the 2nd photo is with both pads trying to put them together.
Image025.jpg
Image025.jpg (204.54 KiB) Viewed 2094 times


cheers all.

Re: a little help with my brakes.

Thu Sep 11, 2008 7:29 pm

Not sure exactly what you have done but that piston does not look square at all. Remove the caliper from the bike.Remove the brake line from the caliper and see if you can square it up by pushing against the top of the piston. I would suspect new seals and a total rebuild might be in order though.

Re: a little help with my brakes.

Thu Sep 11, 2008 8:29 pm

I just did the padds on my ZX-12r. I did notice there seems to be a spacer between the piston and the back of the brake pad. I "disturbed mine and it wasn't sitting square when I went to put the pads back in. It doesn't take much dust/crap for the spacer not to sit square.As suggested take the caliper off and invesigate, however I wouldn't disconnect the brake line just yet. BTW where are you?

Re: a little help with my brakes.

Thu Sep 11, 2008 8:56 pm

The piston must be square in the caliper...... by the looks of the angle it is going in you are in trouble & fingers crossed you have not damaged the sides of the bore :shock: Take the caliper off & use compressed air to carefully push out the piston & make sure you catch it when it pops off :shock: & look for damage before proceeding to push the piston back in square..... hint polish the piston on a buffing wheel to remove any scale that you might have on the surface & you should replace the seals while you are at it as they are an inexpensive part & should be replaced periodically ... use a little high temp grease on the seal before you pop the piston back in ;) as asked before where are you located ?

Re: a little help with my brakes.

Fri Sep 12, 2008 12:15 am

WTF!??

Rubber grease , lanoteck grease or at worst petroleum jelly on caliper piston seals ONLY or you stand a good chance of FARKING the seal and contaminating the brake fluid meaning next job will be master cylinder!!

Fadz you NEVER need that much force on brake calipers , particularly if it was previously working![broke two G clamps???????]

You badly cocked the piston over and have probably now scored the bore with excessive brutality!! Two screw drivers while the old pads are still fitted is more than enough force if the piston is aligned properly!!

Slip you old pads back in or even a piece of flat bar / wood etc with the caliper removed as it is now. GENTLY apply the brakes until the piston frees itself and squares up. Then GENTLY push the piston back making sure you apply EVEN pressure .If it jams , find the high side and push there rather than using BRUTE FORCE AND IGNORANCE!!!

once you push the piston all the way home so it is flush with the caliper body / dust seal you can then fit your new pads and re fit the caliper.
Make sure you pump the brake lever till it gets hard and top up your fluid BEFORE you go for a test ride!!

Hopefully you haven't farked it dude!?

Re: a little help with my brakes.

Fri Sep 12, 2008 5:22 pm

First is first!

im located in wetherill park, near fairfield/horsley park, 10 mins south of eastern creek.

i went to a bike mechanic with a mate for his bike and i asked about my bike he said, in all fairness, DO NOT play with the brakes, tryes or forks of your bike, esp a beginner to the riding world, he recommended to take it in the shop, his prices were very cheap.

i pushed it all the way before it stuffed up without a breeze, and as it closed back up beacuase i closed it back up, it was the biggest mission to open it.

yes i broke 2 g clamps not big ones , one was a 100mm the other a 75mm or 85 mm, i tried to bleed it abit so it can compress back in but still didnt work, its out of square becuase i couldn't fit the whole g clamp over it, i had to do it from side to side. if that amkes sense?

my problem is my bike can't go anywhere, unless i strap the caliper to the side of the bike and take the bike into the shop with no back brakes, Dangerous but do-able.

i hope i haven't screwed it up, but my disc is completly screwed so i need a new one, mca dosen't recieve thier shipment for another 8 weeks, and metro spares is offering me a sued disc for $125, this shop i can take it to can get me brand new ones for a good price.

what should i do guys, if anyone can help me out, that would be awesome for the right price, and if anyone can swing by if near and have a look, that would be great, im really trying to get it back on the road, i want to go for a ride and also for the dyno day.

feel free to let me know what should i do, im not in a rush but i want it done in the next 2-3 weeks.

cheers all you have been great. :D

Re: a little help with my brakes.

Fri Sep 12, 2008 5:38 pm

dude i dun mind giving you a hand let me know when, weekends are best for me :) im in greystanes so im only a fart away from ya.

Re: a little help with my brakes.

Fri Sep 12, 2008 5:42 pm

quote: my problem is my bike can't go anywhere, unless i strap the caliper to the side of the bike and take the bike into the shop with no back brakes, Dangerous but do-able

Mate the only time I actually use my rear brake is when I am sitting at lights. Just take the caliper off completely and take it to a garage. You will just have to replace the fluid when you put it back together, probably not a bad idea anyway.

Good luck

Re: a little help with my brakes.

Fri Sep 12, 2008 6:17 pm

yeah tim, i was gonna ask you if i could swing by when it was running, now its totally screwed, umm ill try to get sunday of work, can you do sunday, pm me back and ill let you know more detials.

i want to sus it out before i take it to the shop, i want to learn aswell, taking it to the shop can't teach me anything,

DONT get me wrong, i don't care about spending moeny but i want to get into bikes more so i wanna learn and teach myself.

cheers.

Re: a little help with my brakes.

Fri Sep 12, 2008 7:50 pm

no worries PM me and let me know
cheers Tim

Re: a little help with my brakes.

Sat Sep 13, 2008 7:01 pm

Good on ya Tim! :rock:
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