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bleeding brakes - who needs them!!


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Faster bike needs better brakes!

Since renewing the fluid I just can't get the same brake performance. I am now using Dot 5 fluid (just as well because last time I managed to squirt it in my eyes), a steel braided hose, original parts brake pads. I have changed the master cylinder seal, bleed, reverse bleed and bleed until I am bleeding fed up. Has anyone lese had these problems? I have to place most of my weight on the peddle to get some decent braking - can't be right.

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I could be totally wrong here, but doesn't the manual for your bike specify DOT 4 for your bike? I use DOT 5.1 which is compatible with the 4, but I don't think DOT 5 is at all. Most Japanese bikes I've seen use DOT 4 and even my brother's KTM.

I've also been in your shoes where the front brakes did almost nothing. It was a b*tch to bleed out all the air that was trapped in the lines (accidentally introduced by me ?) I went and bought a Mighty-Vac vacuum bleeder and that helped a lot. Good luck.

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I think carpeDRZ is onto the problem. What I have read is that DOT 5 is silicone based and should never be introduced to a system that has had any other type installed. Also very sensetive to air bubbles. I read one report of mixing DOT 5 with 4 being compared to putting sugar in the gas tank.

If your brakes did have DOT 4 and you now put in DOT 5, I would recommend flushing out the system by running a couple of pints of DOT 4 through to clean out all of the DOT 5.

I hope that it works out for you. Let us know of your progress.

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and john.. if you do decide to flush, i would definitely recommend the mighty vac.. will make things MUCH easier and faster.. and i had that problem with the front for ever.. i think i bled the front, with a vacuum bleeder for about 3 hours straight.. got arm pump from pumping the bleeder!! i feel for ya

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You definately do not want DOT5. Silicone brake fluid absorbs less water but has a lower boiling point and is more compressible. It will also destroy your DOT4 seals. DOT5.1 is OK. Trying cracking the fitting next to the master cyl and bleeding it there. Mighty Vac is an excellent tool to own.

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Having had similar problems bleeding brakes, I gave up on the conventional wisdom and purchased a $0.50 plastic syringe from the local pharmacy. The connection on the syringe end allowed a 6" piece of 5/16 fuel hose to thread on and then bleed the brakes in reverse ie. from the caliper up. Push the fluid up the brake line and this removed all the bubbles. Once all new fluid is introduced, suck some back into the syringe to get any bubbles sitting in the caliper bleed nipple and tighten.

I have 2 syringes, one for new fluid and one to suck out fluid from the master cyclinder.

Heaps cheaper than a vacuum or pressure bleeder and quicker to use.

(ONLY use dot 4 fluid !!!!) ?

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Here is an interesting tidbit regarding the "Mity-Vac":

When my first child was born, he was in a very big hurry and did not want to wait for adequate staff to arrive. He also had the umbillical cord wrapped around his neck and got "stuck" partway out. Rather than an interested observer, I was pressed into service as a midwife...

The doctor used a MightyVac with a soft suction cup attachment to pull him out!

Left a helluva weird knob on his head! Once we had the cord unwrapped and he was wasn't so blue, I told the doc I had the same exact device at home in my shop. I received a doubtful look. I'll bet the price of mine was a LOT less, though...

The knob did go away, though I definitely had my doubts at the time. ?:D

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My kid was sucked free with a mighty vac too. Now I know what they look like. And yes, she had a bit of a cone head for a few weeks - all gone now though.

I have tried the syringe thing in the past, and it does work very well. So with dot 4 and weekend of syringing I will be able to stop again - hooray.

Merry Xmas

John

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