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throttle's lost its snap....

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Since I readjusted my handlebars the other day, the throttle no longer returns to the off position with a snap, like it did before. It now returns very, very, very slowly....zzzzzzzzzzzzzz.

I tried playing with adjusting the return cable down by the thingie near the carborater. I'm afraid my advanced knowledge of cable adjustment fails me.

Any help would be appreciated.

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sounds like the return cable has snapped or is kincked or has been kinked. i had this prob and the return cable had snapped inside the cover therefore the spring on the carby had no effect.

hope that helps.

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Maybe a kink somewhere. When I twist the throttle off, the return cable has tension and pulls the wheel thingie back in place.

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Cut the return cable off, remove and plug the hole with silicon, it is a major source of a headache.

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Cut the return cable off, remove and plug the hole with silicon, it is a major source of a headache.

Really? Just let the spring do the work?

Which hole needs plugging?

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I bet you have the grip binding on the end of the bars.

Loosen the throtle mechinism and move slightly out on the bar.

I myself, would not remove the return cable .

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You only need a push-pull with a flatslide. If you've got the standard CV carb, you can just run a pull cable.
Not true a lot of us with fcr have only a pull cable. The push cable always freys and gets stuck in the sleave.

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You only need a push-pull with a flatslide. If you've got the standard CV carb, you can just run a pull cable.

ummmm, no. I know of a couple of fcr's that are running only the one cable for sure, rockchucker makes three.

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The fcr is different because the slides on rollers. With something like a TM40 there's the danger of the slide sticking open, hence the push cable.

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The fcr is different because the slides on rollers. With something like a TM40 there's the danger of the slide sticking open, hence the push cable.
If the spring doesn't snap back there is a more serious problem, a push cable would do nothing.

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I believe azvmax has the answer.

I had the same problem with my yz400f. I went through the trouble of replacing the cable. When that didn't work, I accidentally figured out that I had the throttle grip assembly pushed to far down on the handlebar. The spring is not strong enough to snap it back when the rubber of the grip is dragging along the handlebar. I took it off, cleaned all of the smut out of it with kerosene, then re-attached it to the handlebars, making sure I let it hang over the end some, or at least enough to allow it to snap back.

Check it the grip assembly for debris as well. Mine had gunk in it from previous applications of chain lube.

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In 8 years of regular motocross I have had one throttle cable ever fray. I have had the throttle become slow many times and it is always a crushed throttle tube from a crash, dirt under the throttle tube, or the tube is pushed too far on.

Take the throttle housing apart, clean it very well. Clean the handle bar well. Put the tube back on the bar dry, rotate it slowly, if you feel any grit in there, wash it again. Do this over and over untill it is clean feeling. Use a light oil lube (no grease, traps dirt and sticks) and reassemble the throttle. When pushing the assembly into place, push it on untill it stops and back it off just a tad, maybe 2-3 mm then tighten the housing bolts down. The throttle should be fine after that.

Pro taper makes an excellent throttle tube that has a bearing in the end of it as well as a teflon sleeve on the inside. It is extremely smooth and resists crash damage and jamming very well, I recommend them to everyone out there who appreceates a smooth throttle.

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I believe azvmax has the answer.

I had the same problem with my yz400f. I went through the trouble of replacing the cable. When that didn't work, I accidentally figured out that I had the throttle grip assembly pushed to far down on the handlebar. The spring is not strong enough to snap it back when the rubber of the grip is dragging along the handlebar. I took it off, cleaned all of the smut out of it with kerosene, then re-attached it to the handlebars, making sure I let it hang over the end some, or at least enough to allow it to snap back.

Check it the grip assembly for debris as well. Mine had gunk in it from previous applications of chain lube.

In 8 years of regular motocross I have had one throttle cable ever fray. I have had the throttle become slow many times and it is always a crushed throttle tube from a crash, dirt under the throttle tube, or the tube is pushed too far on.

Take the throttle housing apart, clean it very well. Clean the handle bar well. Put the tube back on the bar dry, rotate it slowly, if you feel any grit in there, wash it again. Do this over and over untill it is clean feeling. Use a light oil lube (no grease, traps dirt and sticks) and reassemble the throttle. When pushing the assembly into place, push it on untill it stops and back it off just a tad, maybe 2-3 mm then tighten the housing bolts down. The throttle should be fine after that.

I think everybody's right.

The throttle grip was gummed up at the end of the bar. There was a nice big gooey lump of gunk just sitting there. Degreased, cleaned, washed it all, repositioned the throttle. Works beautifully now.

However, I also disconnected both ends of the return cable. I was curious to see how the throttle would work with it off.

Right now, the throttle is as snappy as can be. In a couple of days, I'll reconnect the return cable and see what the difference is, but for now it returns more freely than ever.

Thanks guys!

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I bet you have the grip binding on the end of the bars.

Loosen the throtle mechinism and move slightly out on the bar.

I myself, would not remove the return cable .

Yes, don't disconnect the cable till you first check to see if the tube is binding/dragging on your bar. I just replaced my bars and added new grips and moose handguards. While cutting the throttle tube, I left too much loose plastic and it naturally got between the tube and bar and gave me the same problem. A light sanding of the end of the tube with a dremel and a strong vacuum of the area, followed by a good lubrication of the bar/tube contact area, fixed the problem.

Now, all is fine. :banghead:

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Quick Note most cables cannot push.

The proper terminology is pull pull.

Think how the cables are working.

One cable is on top of handle bar tube and one on the bottom.

Thus clockwise or counter clockwise rotation of throttle tube pulls a cable.

What appears to be pushed is really being pulled from carb side.

I only know this because I fly remote control airplanes.

Bob

I could be wrong but thats how I was taught. :banghead:

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Quick Note most cables cannot push.

The proper terminology is pull pull.

Think how the cables are working.

One cable is on top of handle bar tube and one on the bottom.

Thus clockwise or counter clockwise rotation of throttle tube pulls a cable.

What appears to be pushed is really being pulled from carb side.

I only know this because I fly remote control airplanes.

Bob

I could be wrong but thats how I was taught. :banghead:

your right I think the term push cable is used to tell the difference between the two.

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First-make sure you didn't push the right bar end weight (if you have it still on) up against the throttle grip. I've seen it happen.

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If the spring doesn't snap back there is a more serious problem, a push cable would do nothing.

Not true; two-cable carbs can function fine without the return spring. I wouldn't do it but there are service bikes that do.

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