Crf250 front brake

Jim Lahey
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1/25/2015
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CA
1/28/2015 3:40pm
Are you sure youre bleeding it properly?
mxer574
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1/12/2012
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Darden, TN US
1/28/2015 3:44pm
Jim Lahey wrote:
Are you sure youre bleeding it properly?
I would say yes. I have a brake air bleeding tool
Jim Lahey
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CA
1/28/2015 4:07pm Edited Date/Time 1/28/2015 4:09pm
mxer574 wrote:
I would say yes. I have a brake air bleeding tool
Ive ysed those, but they dont seem to work too well with small dirtbike brakes. Try bleeding them manually
mxer574
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Darden, TN US
1/28/2015 4:12pm
mxer574 wrote:
I would say yes. I have a brake air bleeding tool
Jim Lahey wrote:
Ive ysed those, but they dont seem to work too well with small dirtbike brakes. Try bleeding them manually
I have tried the ole fashion way also lol.

The Shop

Paw Paw 271
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Benton, LA US
1/28/2015 4:58pm Edited Date/Time 1/28/2015 4:58pm
Try this......Remove the caliber from the fork. Raise it above the master cylinder and then induce fluid into the caliber. This will push out the air back into the master and out. Remember....Air want to rise if you don't get it all out.
Also be sure to use dot 4 brake fluid.

Paw Paw
Dragoo168
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NV US
1/28/2015 8:14pm
Back-bleed as suggested, and if that doesn't work, vacuum bleed, flushing the system. Spongy usually means air.
mxer574
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1/12/2012
Location
Darden, TN US
1/29/2015 3:32pm
Tried this and still nothing Sad
mxer574
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1/12/2012
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Darden, TN US
1/29/2015 3:33pm
Dragoo168 wrote:
Back-bleed as suggested, and if that doesn't work, vacuum bleed, flushing the system. Spongy usually means air.
Also tried this and got nothing
mxer574
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Darden, TN US
1/29/2015 3:34pm
Try this......Remove the caliber from the fork. Raise it above the master cylinder and then induce fluid into the caliber. This will push out the air...
Try this......Remove the caliber from the fork. Raise it above the master cylinder and then induce fluid into the caliber. This will push out the air back into the master and out. Remember....Air want to rise if you don't get it all out.
Also be sure to use dot 4 brake fluid.

Paw Paw
Tried this and still didn't help
motosicko
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Denver, CO US
1/29/2015 4:45pm
Is your rotor bent causing it to drag and push against pad, spreading the gap and causing mushy feeling at lever?
Spin your wheel and watch if your caliper wriggles side to side.
1/29/2015 5:13pm
You still have air in the system. I'm picky about my brakes so I flush and bleed them every two or three rides. Ive spent lots of time on brakes.

Are you using a piece of clear tubing over the bleed nipple so you can watch the air bubbles come out? If not I recommend trying it. Its the only way you can be positive you have purged all the air you can. Use 18"-24" of tubing and route it in an upward fashion then back down into the catch container. This will lessen the chance of sucking air back into the caliper.

Pull the caliper off and spread the pads apart as far as they will go. You may have to remove some fluid from the reservoir so it doesn't spill over. Find two sockets or a piece of wood to place between the pads. Anything that will fit tightly between the pads and solid enough to not be crushed by the pads squeezing it will work. Pump the lever until the pads have a tight grip on whatever you placed between them. What you are doing here is minimizing space in the system where air could become trapped.

Pump the lever and hold it. Crack the banjo bolt loose at the master cylinder, tighten it, release lever. Repeat two or more times while making sure the fluid level isn't too low. The master cylinder should be free of any air now.

Repeat this process for the banjo bolt at the caliper. This will help rid the air in the line itself.

Now bleed at the nipple using clear tubing until absolutely no bubbles appear in the tubing. If you start to see lots of tiny bubbles stop for a couple hours to allow the air to combine into larger bubbles. I always pump the lever slowly as fast pumping is what causes these tiny bubbles.

Remove the object between the pads and reinstall the caliper. Slowly pump the lever while keeping the fluid level sufficient, until the pads contact the rotor. Your brake should feel solid after this half hour of work.

One more thing. Make sure the brake lever pivot bolt and bushing are well lubricated. Ive seen these become dry and rusty causing the lever to bind and drag when applying the brake. It feels like you are building brake pressure but in reality you are feeling the pivot drag.
1/29/2015 7:21pm
Also no one has mentioned using fresh crush washers on both the caliper and master cylinder.
Jack_Wagon
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Location
Conyers, GA US
1/29/2015 8:18pm
If your brakes are spongy and your front wheel drags, chances are that the two are related. Sounds like a bent rotor or an improperly installed wheel.
Dragoo168
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239
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NV US
1/30/2015 9:29am
Like I said before, spongy generally means air. Step back and go over what you've done up to this point, and make sure that everything is good. That includes caliper mounting, rotor thickness/wear, crush washers, cap bladder, Everything!!! As noted, you should have bled the master cyl, the line, and then the caliper, ultimately flushing the system of air. All of the various methods advised, are subject to human error, and is why I use a vacuum (Not a hand pump vac either), and even then, if the fittings are not sealed properly during the procedure, then there is still the chance for contamination of air. If you use one of these, have someone continually fill the reservoir with fluid when you crack the bleeder, and thoroughly flush the system. Remember, it's a sealed system,..it's either drawing air from somewhere, or you're just not getting it all out!
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