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ttomkat510
04-11-2009, 04:13 PM
how do i bleed the rear brakes ? or tighten them, the bike sat for years and the fluid is fine, just the pedal is all the way down and not stopping the bike, i have to push the pedal acouple of times to get it to stop, so i think they need to be bleed, of something, it has a new calaber on it, well new bought 10 years ago and pads, i remember haven to pump the pedal and hold the hose or somthing like a million times, does this ring a bell?

GeoD
04-11-2009, 04:41 PM
Make sure to check the socket bolt and the piston. They have a tendency to freeze up over time. They should move with little effort (pressure). If they move slow or not at all you can try to free them up with some penetrating oil. Maintain the socket bolt with a good greasing at least once a year.

Chapter 14 in the service manual shows you diagrams and "how to" bleed brakes.

Here's some brake bleeding instructions:

1. Make sure all the connections of the brake lines are tight, without leaks. Make sure everything is installed properly.

2. REMOVE RUBBER CAPS/NIPPLES:
The bleed valves, covered by rubber caps, are located on the top of each brake caliper. Remove the rubber cap on each valve.

3. FILL REVERVOIR:
Remove the reservoir cap from the brake reservoir (located on the handlebars on most atv's) and fill it to the top with DOT 4 brake fluid. Make sure the reservoir always contains brake fluid to prevent air from entering the brake lines. So keep an eye on that during the process. Refill the reservoir in time.

4. TAP RESERVOIR:
Gently tap the brake reservoir and shake the brake lever up, down, left and right. You should see air bubbles coming up from the master cylinder where the fluid enters the line. This means fluid is traveling into the lines and down to the calipers, while air is surfacing. Do this for some time and make sure to keep the master cylinder filled. Refill it in time, to prevent air from entering.

5. PUMP THE BRAKES:
Once most of the air is out, pump the brakes. Pump the brakes with extremely slow pulls. Make each pump take 2 seconds, from the lever all the way extended to the grip. If you do it fast, not as many air bubbles are going to get out of the system. If you open the reservoir cap, you can see the bubbles coming out of the line and into the brake reservoir. Squeeze and release the brake lever 15 - 20 times. On the final squeeze hold it in!

6. HOLD LEVER - BLEED VALVE - RELEASE LEVER:
While holding in the lever, open one of the bleed valves on a caliper with an 8mm wrench. You should hear air & see fluid ease out. Once the air stops easing out, tighten the valve, ...and release the brake lever.

7. Repeat steps 4, 5 and 6 for the other caliper. Keep at it until you get a good amount of braking action in the lever, and untill all the air is out of the lines.

Take the bike out for a ride and rebleed to make sure all air bubbles are removed.

dom
04-11-2009, 04:42 PM
Yeah, pump it up.. Then while hold the pedal/lever compressed crack open the bleeder for a second and left some fluid come out. Then close the bleeder and repeat the process until you have clean fluid and no air coming out. Very important to close the bleeder before you let off the pedal/lever. If you keep it open you will be allowing air to get back into the system.

Hope this helps.

P.S. Welcome to the site!


HA GeoD, we posted at the exact same time, your post ended up jumping in front of mine.. Didn't it read it yet, but yours looks a lot more detailed.

GeoD
04-11-2009, 05:03 PM
A couple more words of advice:

Keep the resevoir full when bleedng. Also keep the bleeder hose submerged in the brakefluid (in the bleeder container) when pumping the brake lever. If it doesn't stay under the fluid it will suck in a huge air bubble and you will have to start over.

dom
04-11-2009, 05:07 PM
Excellent write-ups GeoD. Nice detail. Tell you what, nothing beats bleeding the brakes on my hot rod. I simply open the reservoir turn a bottle a brake fluid upside down in it, crack open all four bleeders, come back an hour later put a new bottle upside down in the reservoir, come back 30 minutes later, close all the bleeders and the master cylinder. Pump the brakes and back on the road.