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Discussion Starter #1
Over the past few months I noticed that my 2002 with 10k miles on it was not braking too well with the front brake. I was thinking that the brakes really sucked and I was contemplating buying some new pad to improve the stopping distance. Sometimes I had to REALLY squeeze the brake to stop. Well today I decided to change out the brake fluid for the first time. I found that there was a lot of water in the fluid and some "slime" in the bottom of the reservoir. While bleeding the brakes I noticed that no fluid was coming out of the left caliper. I got the fluid flowing and changed out and what a difference that made. You know what they say....two calipers are better than one. Now I don't need to buy after market pad because the bike now stops on a dime. I am really surprised at how much the fluid was contaminated. But I do ride to and from work rain or shine so I am sure that contributed.

Does anyone know if there is a rubber boot made that will fit over the reservoir to help seal it?
 

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Joe...glad to hear you got the problem fixed. For a single action, single piston caliper system, the VN750 brakes are excellent.
You're good to go for another 8k on those pads I would think, but check the color of the DOT4 in the little window periodically. There was a rubber boot inside the MC cover, right?? That's your only air/moisture seal, and it deforms very easily...make sure it is seated as perfectly as you can before you put the top on. I've never seen an aftermarket 'condom' for the MC, but I'd bet it would be ugly....
When you change the pads, I would go w/ stainless steel lines (see the 'Brakes' section). Add some better pads, and you'll be able to give change back from that dime....
 

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The seal was in good shape and there are no leaks. The lever has always been firm. My only guess is that moisture is getting in through the cap. I thought of putting a little RTV around the cap, but that would not look very good. But a form fitting rubber boot over just the top may not be too bad. I'm not going to give up riding in the rain (I did'nt buy the bike so it could sit) so I guess I'll jut have to keep a good eye on the fluid color.....
 

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While bleeding the brakes
I had my front forks off earlier this week, and decided to replace the brake fluid as long as it was apart.
I could not get the brakes to come up to where they are supposed to be. I bled them 3-4 times, and could see no air anymore in the system, but they just would not cooperate.
I finally in desparation I took it to my local Kawasaki shop, and they used what they called a power bleeder. What it is a vacuum pump. They suck the fluid out from the bleeder valves at the calipers thereby sucking the air out along with it. I guess it is the opposite of just bleeding the brakes using pressure with the brake lever. Anyway all is back to normal.
I'm glad to hear that you didn't have the problems I had.
Bob
 

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Re: To brake or not to brake-brake bleeding

choppbobby said:
I had my front forks off earlier this week, and decided to replace the brake fluid as long as it was apart.
I could not get the brakes to come up to where they are supposed to be. I bled them 3-4 times, and could see no air anymore in the system, but they just would not cooperate.
I finally in desparation I took it to my local Kawasaki shop, and they used what they called a power bleeder. What it is a vacuum pump. They suck the fluid out from the bleeder valves at the calipers thereby sucking the air out along with it. I guess it is the opposite of just bleeding the brakes using pressure with the brake lever. Anyway all is back to normal.
Bob
They used what is called a 'Mity-Vac' type device...you can get one online for about $35 I think.
Brake bleeding can be a pain! If the 'regular' way doesn't give me the feel I want, I use the 'reverse bleed' method. I have a decent size syringe bought at a farm supply store (Farm&Fleet or Tractor Supply)...used for giving horses medication. After bleeding off as much air as I can see using the regular way, I fill the syringe w/ DOT4, connect to the caliper bleed screw, and 'inject' fluid UP the brake line.
You will see bubbles galore come up thru the MC, so make sure it is only ~ 1/2 full when you start, and use plenty of rags to mask off the area.
This normally works great, but I have had to squeeze the lever and tie it up overnite on occasion to get it perfect.
 

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'inject' fluid UP the brake line.

Thanks for the suggestion Jim.
I don't know why the small brake system is so hard to bleed. I've bled car brakes before without this kind of problem.
Anyway, now I know how to do it.
Bob
 

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I installed Galfer braided stainless steel brake lines recently, wow - what an improvement! After install I bled them and then tied the lever back twice but the lever would quickly get mushy within a 30 mins of use. I bought a MityVac at the local autoparts store and it worked like a charm - sucked out those pesky little air bubbles that my normal methods couldn't remove and the lever is now way firmer than new!
 

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sucked out those pesky little air bubbles that my normal methods couldn't remove and the lever is now way firmer than new!

Something just occurred to me. When you are sucking the fluid out from the bottom, do you leave the top of the master cylinder open? and I assume you must keep adding fluid as you go, so the master cylinder does not go dry.
 

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Correct, if you don't you will end up with a ton more air in the system.

RB

choppbobby said:
... snip...
Something just occurred to me. When you are sucking the fluid out from the bottom, do you leave the top of the master cylinder open? and I assume you must keep adding fluid as you go, so the master cylinder does not go dry.
 

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Bruce said:
I installed Galfer braided stainless steel brake lines recently, wow - what an improvement! After install I bled them and then tied the lever back twice but the lever would quickly get mushy within a 30 mins of use. I bought a MityVac at the local autoparts store and it worked like a charm - sucked out those pesky little air bubbles that my normal methods couldn't remove and the lever is now way firmer than new!
I use one of these pretty much daily at work, and it's a life saver. It beats the hell out of having to borrow someone to pump the pedal during bleeding, and it's much faster.
 
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