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Author Topic: Big Bear Brakes  (Read 794 times)

Offline machelis

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Big Bear Brakes
« on: May 27, 2009, 10:47:43 PM »
Trying to prep my dads '96 Big Bear for some hard work this summer, but having problems with the front brakes. They've been real soft the past year or so (which is why I'm going over the whole quad right now) and want to be able to stop without having to pump 3-4 times. I just bled them, but they're still pretty soft. No leaks in any of the lines or connections. Little bit of dribble coming from the master cylinder cap. Also adjusted the shoes a little bit as well as cleaned all the slaves and springs thoroughly. Could an aged seal be the reason it won't stop?

Thanks.

Offline Krandall

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Re: Big Bear Brakes
« Reply #1 on: May 28, 2009, 09:23:45 AM »
Could be one of a few things possibly.

Dribble from the master cylinder cap is part of it. Because when you apply the brakes, it puts pressure on the cap, when it leaks, you're losing valueable pressure.

possible that brake lines are flexing from being over 10 years old. if they are rubber, could be time for replacement.

I see you said "Shoes" I'm assuming you have drums then.

It could be the fact that drums just don't have the stopping power like a nice rotor/caliper style :)


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Offline machelis

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Re: Big Bear Brakes
« Reply #2 on: May 28, 2009, 10:33:47 PM »
Thanks for the reply Krandall.

The drums used to be able to stop the 500+ pound beast on a dime, then after a weekend of riding they just stopped stopping  ???

We've checked every possible option including the ruber brake lines. If they're flexxing, it isn't enough to see by eye.

My buddy called me this morning saying that it could be the diaphram in the master cylinder. Could this have taken a crap all of a sudden?

I'm going to pop my the local Yammy dealership tomorrow and see what info their guys can give me. They're pretty good with mechanics.

Offline Krandall

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Re: Big Bear Brakes
« Reply #3 on: May 29, 2009, 10:35:43 AM »
I know once drums get any bit of water/dirt inside they just suck @ stopping, that's the way it was w/ our old three wheeler. Once we took it through any mud, stopping was over rated. :lol:

Hmm, I woulnd't htink it'd be an "all of a sudden" kind of thing with the master cylinder diaphram..


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Offline machelis

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Re: Big Bear Brakes
« Reply #4 on: May 31, 2009, 06:02:14 PM »
The drums were relatively clean inside, concidering the age. I didn't get a chance to squeeze over to Yammy, but when I get some time I'll be tearing apart the master cylinder to see if I need to get the rebuild kit for it. Worse comes to worse, send it to Yamaha and have them fix it. My dealer is oddly enough very competant.