bleeding front brakes

[handsomejackuk]

Hi,

recently touched up my front banjo fittings as they were showing signs of Rust (M.O.T.) Failure. In doing so I only cracked open the banjo bolts lightly to get a bit better access to the brake lines, but obviously inroduced some air into the system. On continuing maintenance to the front brake system I decided to strip the caliper down completely and polish pad retaining pins,copper grease the pins, clean up brake pads, as there is still a bit of life in them, also copper greased the sliding part of caliper as that seemed a little stiff. Have reassembled caliper and decided it was probably time some new fluid should be introduced. Spent a couple of days with varying succes in trying to bleed the brakes. Did borrow a one way bleeder valve thingy off a mate this was no use at all. let the bike stand for a few days as have no use for it at moment, however did attempt to sort brakes again today with a piece of plastic hoes and tried bleeding again. Seems to got a bit more lever feel, but not as good as it was before i started this exercise. Have read some tips about tying brake lever overnight as this is supposed to get rid of more of the air. Will try again tomorrow.

Does anyone know what is the point of the adjuster screw on the lever. I tohught with Hydraulic brakes they should not need adjustment. Please fill me in on the reason for this adjustment. It is not for Brake Span as in adjustable levers ?

regards for now Jack

[Bill Jurgenson]

theoretically, you can bleed the system just like a car:
open reservoir and fill to brim;
pull up pump and hold;
crack bleeder;
tighten bleeder;
release pump;
do it again...
This as long as it takes to force the air in front of the fluid out thru the bleeder = an eternity.
Up front, you can fill up the reservoir and open the bleeder more than just a crack and let gravity do its job, being careful to check that the reservoir does not run empty.
Best and fastest way is to use a vacuum pump made for the purpose to suck down the fluid from the top.

all of this described here

I use this tool: MV6820

the screw in the lever is to adjust the amount of lost motion, i.e. how far the lever travels before pressure is built up.
BE CAREFUL fooling around with this. If the screw is too far in, the the piston will not back up all the way to the opening into the reservior and the front brake will lock up as soon as it is warm.

[dozzyd]

Hi,
You might want to take a look at these 'speedbleeder' nipples. I fitted these to my BM ( Brembo brakes are notorious for holding onto air ! ).
They come from the states and come with all insructions, very simple and worked a treat. It works with a one way ball valve inside the nipple, so you crack it and pump the leaver three or four times, no need to keep opening and closing the nipple.
I had a quick look on their website but they don't list MZ, i'm not sure if the MZ brakes are fitted to other bikes. you could try an email to them, they seem helpful and communicative. Good luck. http://speedbleeder.zoovy.com

[handsomejackuk]

THanks for that, will try bike later I thought the speed bleeders wont work on MZ's because they have a ball bearing in the bottom of the cylinderI remember doing the rear brakes and the nipples are different to the standard

THanks Anyway

Jack

[rodge70]

had the same problem with the rear caliper on the 125 the other day,literaly cracked the nut to re position pipe,tried bleeding the usual way but no end tiny of air bubbles in the tube,i then pushed the pistons all the way in with the bleed nipple open then topped up resevoir and pumped new fluid through in the normal way,tube and jar of old fluid,and after a few minutes pedal was nice and firm and the rear wheel will now lock up if needed.

[handsomejackuk]

checked bike out today lever seems a lot firmer after tying it up last night. Unable to road test as Had to M.O.T. My trx850 today, will give it try tomorrow if time allows.

What you up to on the weekend Rodge ?

Will Try and get out on one of the bikes on the weekend I Weather is good. Sat and Mon available but Sun Will Be at Home With Kids as other half is working.

May Make my Way down to Bristol One DAy On TRX850 for a nose around Fowlers, Kawasaki Centre, Maplins,

Let me know if you are about at all rodge. would like to see the trail tech as still keen on getting one.

B.T.W. how did you get on with Gerrard Re:- wheel rebuild ?

Regards Al.

[rodge70]

hi alun,hope to be off racing mower this weekend,providing field not water logged!!.if your going to fowlers,i'm 1/4 mile up the road from there and i'm working localy next week,so no probs on a visit,cheers.