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Discussion Starter #1
Finally got my 90 650 to idle however when its idling it sounds like it wants to shut down. (Blahhhhhhh engine sound) Have to feather the throttle to get it to move. From 1/4 to full throttle the engine runs fine.

Here is some info:

1) After riding I smell like gas

2) When warm and idling, if I flick the choke cable on for a second the engine comes to life (sounds like its supposed to)

3) I have adjusted the pilot air screw one full turn out (clymer) and this is where it sounds the best, and only spot it will run.

4) If I dont drive it hard I am getting backfiring in the pipe.

5) No modifications have been done.

Help.
 

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to me it sounds like jetting problems or the floats are adjusted wrong. Sounds like what my sled was doing before the coil went out.my sled has pretty much the same motor as yours only older. (600 triple bored .040 over)i adjusted the floats and all was good again the motor was being fed too much gas and was dogging on the low end idle hope this helps at all

bobby

My wife said its me or my sleds... Im sure gonna miss her
 

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Sounds lean to me. Like when I brought my sled from ambient 5000ft back to sea level I got some popping when I tried to give it a little gas. Lean is the bad side to go when you are setting up. Have you pulled the plugs? what condition/color are they?

Giving a little choke should actually kill the engine when warm, not rev it up. that means when you flick the choke you are throwing more fuel to the cylinders. I'd pull your carbs and check the size if the main jets and idle jets so you have a base line to work from. You'll get lots of help from there.

what altitude range are you running at?

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I think.... therefore I sled
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Two '94 Indy XLT SKS
 

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Discussion Starter #4
I also thought it was running lean. Plugs are wet and oily. Not carboard brown. Unsure why I would have to change anything as all is stock and ran ok last year. I will check the floats, sled has 4,000 miles on it, never changed the floats.

I am wondering if I should bring it into the shop, hate spending money if I could avoid it. Any one fix sleds in the Toronto area in Ontario Canada that is cheap and honest?
 

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We had a similar prob on one of my brothers sleds. he smelled like gas too. it was pouring out of his float bowl and his sled would back fire and run like crap. he had a couple problems:

Obstruction in carb
bad cdi

This led to a detonated piston.

I need spellcheck!

91 RXL/SKS 650
91 Exciter II 570
 

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You smell like gas becuase there is an overflow tube off the carbs going probably to the handlebars. You may have a bad float valve.

The popping may be due to water/ice in the gas. Get rid off all gas (every drop) in the sled and put in new with a some water dryer stuff. Its a good idea to put this stuff in anyways.

 

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one comment I smell like gas after riding my sled or four wheeler. IT is called riding a two stroke. I mean there could be another reason in this case and I am sure there is but whatever jsut commenting.
 

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two very different smells between raw gas and 2 stroke exhaust. 2 stroke exhaust good!!

 

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Discussion Starter #10
I have had the carbs appart a few times and I am unsure how to adjust the float level.

Any help would be appreciated.

Thanks
 

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For Triples take the carbs completely off the snowmobile. Remove the float bowls. Holding the carbs by the rack. Looking at the carbs inlet needles and rotate the carbs till the float lightly rests on the needle (Aprox. 45 degrees). Measure from the float bowl gasket surface to the top or highest most part of the float. Be sure to measure at both outer edges to make sure its straight or even. If its out of spec pry or bend very carefully the tab that rides in the center of the float to adjust the height. You might have to twist it to make it even on both sides of the float. After spec has been set, reassemble carbs.

from nys-srx

Vmaxyam
 

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I had a similar problem with my XCR 440. But it was partially exhaust valve related.

The other part involved me putting in 1 size larger Pilot jet, that fixed it. What you should do is make sure your Pilot jets do not have junk in them, and make sure your carbs are in sync



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