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jivenene

99 WR400 decay

10 posts in this topic

Just wanted to share my experience of a few rubber parts malfunctioning all simultaneously.

1) petcock o-ring/base gasket

2) float bowl gasket

3) needle valve

I walked into my garage and smelled strong gasoline one day. The petcock and carb. had gas all over them. After some dismatellation, i replaced the petcock rubber, and float bowl gasket. I reasembled, but still had gas pouring out of the carb overflow tube.

I drained the fuel system, and took the carb float bowl off. I manually pushed the floats up to seat the neddle valve (rubber tip), but could blow air past the seal (blowing into the gas tank side of the fuel hose). I removed the needle and seat, and covered the needle tip in a thin film of silicone (did not want to spend $30 and 7 days waiting for parts). I wiped it off, and reapplied, and wiped off again. The silicone filled in any microscopic pits/scars on the needle head (after it dried it had a glossy new look, not like the dry rubber look it had before). I then treated the needle seat to some silicone around the o-ring, just in case fuel was getting past there. I reassembled after 24 dry time, and presto, the sh*t worked (i did the blow test again but this time no air went past the needle valve).

I just found it interesting how 3 rubber parts failed all simultaneously.

On another note, i inspected the swingarm linkage and bearings. The needle bearings either had a whole lotta dried grease in them, or have a plastic/rubber cage for the neddle rollers. Anyone know if this is expired grease or a neddle bearing cage?

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ALOHA

Sounds like you had your hands full with the fuel problem.

On the bearings for the swing arm, I justy repacked mine three weeks ago.

All i could hear any time the rear suspension released was a bird chirping.

Removed the rear tire and rim assy and took out the 10mm bolt,used screwdriver tip to remove bearing cover and seal and found two cages(one for the left and one for the right) with bearings inside like the size of a nickle.

I think that's the bearing your talking about? :banghead:

if so easy repack used like a thimble full of all purpose grease in the paml of

my hand and repacked and reinstalled lubed the seal for bearing also be fore reinstallation.

hope that helps

WReckless :banghead:

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That's not dried grease in the needle bearings- it's a cheesy plastic permanent lubricant. I don't see how it's supposed to work, so I pulled mine apart and put grease in its place.

Kind of makes sense all the rubber parts went at the same time. They are all made of the same substance and are all the same age.

New word of the day: dismatellation :banghead:

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Kind of makes sense all the rubber parts went at the same time. They are all made of the same substance and are all the same age.

Not to me. What you described sounds like damage due to contaminated gas, high methanol content, or the use of additives. Those parts usually don't deteriorate at the same rate unless they come in contact with the same contaminant.

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ok... it did seem kinda odd. I have never seen grease harden up like that, so it makes sense that it is some kind of "permamnent plastic lubricant". Anyways, the rear wasn't making any noise, but i wanted to check out the bearings after reading a few posts here about inadequate grease from the factory. This bike has not seen much water, so everything is still pretty well lubed up.

I live on Maui. It's a mixed blessing. The surf is good and the water is warm, but there really isn't anywhere to legally ride the dirt. No OHV park, and only 1 motocross track. Too bad i can't ride the track, i really don't know how to pull jumps... some day maybe i'll learn. Until then it's cane roads and ranch land...

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ok... it did seem kinda odd. I have never seen grease harden up like that, so it makes sense that it is some kind of "permamnent plastic lubricant". Anyways, the rear wasn't making any noise, but i wanted to check out the bearings after reading a few posts here about inadequate grease from the factory. This bike has not seen much water, so everything is still pretty well lubed up.

I live on Maui. It's a mixed blessing. The surf is good and the water is warm, but there really isn't anywhere to legally ride the dirt. No OHV park, and only 1 motocross track. Too bad i can't ride the track, i really don't know how to pull jumps... some day maybe i'll learn. Until then it's cane roads and ranch land...

AND BEAUTIFUL RED DIRT

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and covered the needle tip in a thin film of silicone

Keep an eye on this repair. Many silicones have limited life when exposed to gas :banghead:

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Not to me. What you described sounds like damage due to contaminated gas, high methanol content, or the use of additives. Those parts usually don't deteriorate at the same rate unless they come in contact with the same contaminant.

This is what I was thinking also. I know a guy who used octane booster all the time. Swore by it. Anthing rubber or plastic became brittle and fell apart including his gas tank.

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