Lately the front brakes on my 1999 kx 250 will lock up after the bike has sat a while. I am able to release the pressure by simply opening the bleed valve at the caliper. The brake will perform normally but again, after I have parked it for a while the same problem occurs and I go through the same process all over again. What do you think is the problem?

SOURCE: bleeding front brakes

Bleed the master first, make sure that there is plenty of fluid going through there and all the air is out. Then, once the master is fully bled, the fluid will pull through the lines quickly. Just do one line at a time, and once you do them both and get good pressure you want to zip tie the lever to the bar overnight to make sure you get all the little bubbles out. Hope that helps.

SOURCE: Kawasaki front brake problem

you need to bleed the brakes real good you have air in the line or caliper this happens when you disassemble the caliper hope this helps give us a rate

SOURCE: bleeding front brakes

Your $7 bleeder kit typically has a near useless one valve in it. Forget the kits such as these, they usually make things confusing for you.
Firts, make sure all teh brake lines are tightly connected and in good condition. If the flexible lines are over 5 years old, conside getting new ones made/fitted. Stainless/braided lines look good but are NOT necessary for any road bike.

All you need is a long piece of clear hose line (fish tank air line tubing usually works well) that fits the top of the bleed nipples very firmly. The hose should be long enough to hang over your handle bars, or be suspended by a wire or string so that the open end is higher than the master cylinder. You can use two such hoses and do both front calipers at the same time if you wish.

First, manouver the handle bars so that the top of the master cylinder is as level as possible, even to the point of undoing the grip clamp and rotating the whole assembly around the handle bars a bit. Then fit the clear hoses to the caliper bleed nipples.
Remove the top of the master cylinder reseviour and make sure the fluid is topped up. Watch this level the whole time, it is important that the fluid level never get below half full or you risk reintroducing air into the brake lines again. Never reuse old fluid, and always filter any new fluid that has been in the brake system before (run it through a new fuel filter if you are that hard up for money) you reuse it.
Then crack open the bleed nipples on the calipers so that you see fluid start to rise up the hoses ( which is why you want clear hoses). You can pump the lever a few times to get things happening quicker, just watch the master fluid level!
Keep pumping the lever and topping up the fluid level until the level in the tubes is at the same level as the master cylinder. Leave the bleeder nipples open and leave the bike alone for an hour.
After an hour, close the bleeder nipples and top up and refit the master cylinder reserviour cover.
Use a jar under each hose to catch the fluid, remove each hose from its bleeder and let the fluid drain out into the jar. Ditch the used fluid.
Reset the grip to its proper position if it was moved and test the brakes. Pump the lever two times and then release the lever for a few minutes ( at least 1 minute) If the brakes are still soft or wont hold pressure ( if you still have to pump the lever to get pressure, dont ride the bike!) then suspect worn master cylinder or buggered seals.

SOURCE: rear brake problem zxr750

hey there,, just gonna guess that u are tryin to bleed the caliper with it on the wheel already,,if u are m8 then itl take ages to pressure up,, im takin it that the caliper has never been split appart b4,, so any way,,take the caliper off the wheel ,but still leave it connected to the brake line,,take pads out to, and just place a pad in between the to pistons,,fill up the resevoir with fluid,, leave the cap off and just put the rubber cap in ,,start pumpin the foot brake,u should see the pistons moving,,keep pumpin till the pistons are a fair way in,, then if u have some put some copper grease on the pistons, then prize them back in,,then replace the pads then pump the foot brake again,just to check,its all moving,, put caliper bk on the wheel ,then bleed as normal,, gettin all air bubbles out,, ,hope that all makes sense m8,, any probs ,,shout and stage 2 story il tell yuh,, cheers now

SOURCE: 1992 ZXR 250 Ninja locked ignition & brakelight stuck on

Try jiggling the handle bars as you turn the key to relieve the pressure off the ignition lock. The kawasaki's have one position past the off "Lock" position that is called the "Acc" this will leave your brake light on. So the key switch goes "Acc", "Lock", "On". Make sure your key is in the Lock position and not the Accesory position