Brake trouble !

[christovski]

Hello,
    i just got my first bike a 92 Honda CB-1. its in quite a state so i have been going though giving it a service with info from the internet and friends but i have got to the brake and i have no idea what i am doing. i saw the pads where low so ordered some more and when i took the front calliper off i could not get the pistons to move back at all so i gently pushed them back in using a G clamp, put the pads in but after i resembled everything the pads are sticking badly (i can spin the wheel but take effort) then i thought i would leave it and go the the back brake but when i was trying to undo the rear callipers retaining pin someone had put a imperial Allen key into my tool box and without thinking i forced it and fecked the pin =( ! i have ordered a replacement rear calliper from ebay.
   i am stuck because everything i can find on the net talks about what to do once u have the calliper off and on a bench. i am sorry if this is a stupid question but i cant just undo the banjo bolt while the brake system is under pressure    so i would appreciate it if anyone could explain how to do this in simple terms. secondly with the front brake am i correct in thinking i should just need to replace the seals and give it a good clean ? also how can i get the stuck pistons out ( i don't have a air compressor )

Many thanks

[Drewski]

Yup, just undo the banjo bolt and leave the end of the pipe to drip into a jar. Before you do, remove the caliper with the hose still attached and slowly pump out both calper pistons with the brake lever - it's the easiest way to get them out. One will move before the other, when that ones almost out, jam it with a piece of wood or similar and pump the other one. Don't be tempted to grab them with a pair of pliers or similar - you'll just damage them. Also, apply some penetrating fluid - (I use Plus-Gas) to the bleed nipple to let it soak before you attempt to loosen it later on - they have a habbit of snapping off if seized. Once the pistons are removed, take out the seals and examine the groove that they sit in. You will more than likely find corrosion in them. Clean the grooves out, lightly coat the new seals with some lubricant, (preferably not petrolium based - sometimes you get a little pack of white grease with new seals), then stick them back in the grooves and carefully replace the cleaned pistons. While you have the caliper off, I would drain all the old fluid. Try and get as much of it out as possible before replacing with fresh.

                  As far as the seized bolt on the rear goes, do you have a pic so we know exactly what we're dealing with? Whereabouts are you?

                 

[christovski]

Thank you for your help, i found there was alot of crap behind the seals in the front caliper but after cleaning them up and putting some new seals in everything is working properly. with the back caliper the one of ebay took for ever to arrive and when it did it was ina  shocking states ( pistons was stuck and pitted to hell, bleed nipple was rusted though and there was only a dust seal inside = / ) anyways i swapped all the inners from my orginal and managed to get one decent caliper out of it.

Many thanks