bleeding front brake

Anyone ? How to bleed master cylinder and front brake

1984 Kawasaki kz550ltd f2

What state are your brakes in at the moment? are they seized ?do you need any new parts ie seals pistons lines? Put up a few photos of what you have and then people will be able to help

Have back brake..absolutely nothing in front.no pressure on brake handle..

Bleed as you would any hydraulic system, use DOT 4. Service manual stuff

top tip is get some penetrating oil, 'plus gas' or similar on the nipples(s), and use a tight fitting ring spanner -they round off easily. The last 10 pecent you can reverse bleed, allowing the bubbles to float up through the master cylinder by slowly pumping the lever...sometimes I do this several times over a few days to get that rock hard feel on the lever.

There are a few good ways.

1: Gravity bleed. Fill up the reservoir with DOT4, attach a tube to the bleed nipple and run it to a jar. Crack open the bleed nipple. Once it starts draining, leave if for a while but keep an eye on it. When the fluid gets low, top it up again and keep topping it until the only fluid left is new clean fluid. Then close off the bleed nipple. I've had good success this way with cars, but never tried a bike. Also, I'm not sure this flushes the system as well as other methods.

2: Bleeding kit. This has a one way valve. Attach to the bleed nipple, crack it open and pump the brakes a few times. The theory is the valve will let fluid out, but won't let it return. Pump a few times, top it up, pump again. I've never had good luck with these, the valves never seem to close off for me, but maybe I've only ever used dud kits.

3: Syringe. I've done a couple of motorbikes this way, and it seems to work well. Attach a tube from the syringe to the bleed nipple, crack it open and draw the fluid though.When the reservoir gets low, top it up, and repeat until the fluid is clean.

4. Manually. This is easiest with two people. Attach a tube to the bleed nipple and run it to a jar. Crack open the bleed nipple. Push in the brakes. Close the bleed nipple. Release the brakes. Repeat and top up the fluid when it gets low. This is pretty fool-proof.

The hardest thing to do is bleed when the lines are empty, especially when they are old lines. Be sure not to completely empty the reservoir, or you will have a bad time - air is compressable, so if your lines are old it can be hard to pump the air out.

If you get lots of resistance when bleeding, it's most likely the hose. They can look fine from the outside, but with age they will often swell on the inside and restrict fluid. Probably the cheapest part to replace too.

The master cylinder has two holes that the fluid feeds into, one of these is a return hole and id tiny and usually blocks up,get a piece of tiny wire and make sure that hole is clear or the brake will come on when it gets hot, and generally be difficult to bleed.

If you're doing the manual bleed method, put a loop in the drain hose and keep it above the caliper. The trapped brake fluid in the bottom of the loop acts like a check valve and keeps the escaping air from going back to the caliper.

Here's a budget vacuum brake bleeder idea...

www.kzrider.com/forum/21-tools/318093-bu...brake-bleeder#318093

When I went to replace/flush the brake fluid on my 79 the master cylinder clogged up and froze, preventing the new fluid to bleed through the system. I took apart the MC and cleaned it all out. Found gunk clogging both holes at the bottom of the reservoir. In my opinion time well spent getting to know your MC.

I posted my process here about a year ago:
www.kzrider.com/forum/5-chassis/595650-b...-problems-101#646554

If you take you brake caliper assembly off the bike, clean off the caliper pistons with some WD-40 and a clean toothbrush, then you can open the nipple and manually push the brake caliper pistons in forcing out the brake fluid. Open the brake reservoir first and apply pressure to the brake handle and then tape the brake handle down first. This should keep brake fluid from spraying out of the reservoir when you are squeezing the brake caliper pistons. Don't get the brake fluid on our paint. After you have pistons pushed all the way in, pump brake fluid back in from the handle. repeat until the brake fluid is clean.

[quote="with some WD-40.[/quote]

WD-40 is not a good idea on this type of repair... just my opinion