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Discussion Starter #1
The sled is annoying me. Seems to only mess up when its warm..

I can usually ride it for about a 1/2 hour before it screws up.

Then it''ll slowly start to bog out from just above idle to about 3/4 throttle... past 3/4 throttle it''ll run strong. But if you let off and get back on it, it bogs. Also it will still idle beautiful!!

The last three times i went riding it ran good for about 10 minutes the first time... later that night it ran good for about a 1/2 hour and then last night it ran good for about an hour before any problems.

I know its not clutching. Battery is good.
 

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Dont you love those EFI Polaris sleds. Could be a couple of problems. Throttle position sensor, temperature sensor or basically the good old computer. My bro has a 92 500 sp efi and my bro-in-law had a 92 650 RXL. When the sleds heat up the fuel system leans out. The temp sensor tells the computer that the engine is warm and lean out the fuel. The problem is when you stop and shut off the sled for a while when its really cold out, the engine cools off quickly but the computer is still in warm mode and doesnt allow enough fuel to start the engine properly. In other words, pull your arm off. On the RXL my buddy had a 'fuel enrichment system' put on his sled. This was available from Polaris to help with the cold/warm starting problem. It basically tells the computer to richen up and dump more fuel in. Sounds like your bog is either too rich or too lean. When the problem starts happening, shut her down real quick and pull the plugs. They should be burning clean, if they are wet, too rich, dry, it may be too lean. The computers on these suckers are known to go on any given day. Either totally or intermittantly. I saw several on ebay for around $100.00 bucks. Some NOS. I hope you can find someone with the old testing equipment for the electrical system on the fuelies, because that would help you out greatly. Good luck.
 

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i have heard people have a lot of problems with these polaris early efi sleds....pesonally i would avoid them
 

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It's a love/hate relationship with these machines....a neighbour of mine owned one (RXL) a few years back and swears by it. '01 XCR 800 is what he's got now and all he ever talks about is the 650.
Sorry for not posting any real advice....Good luck on fixing the problem.
 

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Discussion Starter #5
i checked the plugs when it happened and they were dry with a good color. i took a compression test and the clyinder near the clutch was 115 the middle was 120 and the one towards the crank was 110. ??? hmmm... doesnt sound too healthy to me. i also have a big bog on take off. i have an almond spring in the primary and a stock helix with a red spring in the secondary. ive gold and orange in the secondary and noticed no difference. the bog on take makes me loose when i race. wish i could get rid of it. any help is helpful.

3 IN A ROW MAKE YOU GO!!!
 

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Compression sounds OK to me...not great, but accecptable....oh and did you do this test with the throttle wide open???? If not redo the test and hold the throttle wide open. If the plugs looked good, then i would be looking for worn clutch parts and or drive belt.
 

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Discussion Starter #7
when it happened i was wide open. i was on a rail road bed...thats what we call it. it where the railroad tracks used to be its long and straight as far as the eye can see. i was on there and i had it wide opened then i stayed on the gas and hit the kill switch when i got my reading. ive heard that if compression is low then it could cause this to happene because the gas gets down to the bottom of the motor cause a bog. does that make sense


3 IN A ROW MAKE YOU GO!!!
 

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i've got a 91 rxl,the first season i rode it i had a bog and it would load up when riding slow on trails,afterv taking a good look we noticed the air sensor on the side of the airbox had a broken wire,fixed it and got rid of the problem.just an idea.is your sled stock? compression sounds ok to me,a variance of 15 pounds is considered bad, mine runs 125 to 118. good luck.
 
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