help needed please, almost stranded today

[Jfet]

My wife and I rented a polaris 550 2 stroke to ride along with our new to us Yamaha RS Rage (2007). Things were going great until we stopped for lunch, about 15 miles from our truck. When I pulled to start the polaris 550, the pull rope snapped and there was no remaining end. I rode back to the rental dealer to ask what to do and they told me to wrap a rope around the and start it that way. Made sense, should have thought of that myself. On the way back to the disabled Polaris, the Rage started to backfire and lose power at around 20mph. Giving it more throttle did nothing...actually made it worse. I turned around and headed back to the rental, but it started running better (but it was now downhill) so I turned around again and continued to the Polaris. It worked ok for a few miles, easily getting to 35mph, then would start to die and could only be nursed along at 20mph. Long story short, I made it back to my wife and the Polaris and we tried 20 times to start the Polaris with the rope but no go. We doubled up on the Rage and rode back at 20mph or so and it did get us home. I always had the feeling from the throttle that it would have started to lose power at times if I goosed it. Strange, and I don't know what we can do...wanted to ride tommorow. :-(

Any idea what could make it sometimes lose all power above 20mph and backfire? Then a few minutes later have plenty of power? I had lots of snow being tossed up on the radiator, and no cooling light was on...

Thanks for any help.

 

[yox185]

Gas, plugs, and carbs. I'm assuming that was your first ride with that sled. Was the tank full from the previous owner or did you fill it? Maybe the gas is bad. When you restarted after lunch did you start it and shut it right down? Plugs could have fouled. Or it could be dirty carbs. If it starts up tomorrow and idles you can rule out the plugs.

 

[Maineman]

1st ride ? I bet money on the gas.. I had the exact same problem and when I siphoned the gas out into clear containers you could see the watery mix settle to the bottom. My sled would start to run bad then the "crap" would shift to the other side of the tank and it would run good for a while, then it would shift back and run bad again.

 

[Crewchief47]

Possible TORS issue as well.

 

[vogelm1]

I was thinking TORS too...sometimes if the throttle cable binds up on something along the way down the handle bars, it's enough to trigger the TORS (throttle override system). If you try new gas, you may also want to download a manual from this site and study up on how to adjust your throttle free play. Also double-check your throttle cable is routed nicely with no binding while turning the skis all the way left and right. I'd bet on one or both of these was what caused the issue.

 

[Jfet]

Thanks for the suggestions. I guess it could be the gas, but I am not in a place where I can drain the 7 or so gallons and refill.

The TORS malfunctioning sounds possible, although I don't remember seeing a code 84 on the gauges. When we were nursing it along at 20mph the RPMs were right around 2800 or so, which would be the sweet spot for TORS? But the strange thing is that pushing even more throttle would cause the speed to *decrease* and popping/backfiring. I then let off and drop back to very little throttle for a minute or so and suddenly could feel the machine had power, so I gave throttle and it quickly got to 40mph and was easy to hold there...until I slowed down to 20mph again and would have the same dying of power and backfiring.

I kinda want fuel injection

Edit: One other tidbit. This could be in my imagination because I was quite tired from 20 or 25 times wrapping the cord around the polaris clutch and trying to start it, but when I felt the three spark plug caps on our Rage, one felt cooler than the other two. If only 2 cylinders were firing, could it cause the poor power at higher throttle symptoms? And the popping/backfiring?

 

[RSVECTORFREAK]

First thing i would try is a new set of plugs!

 

[Maineman]

No need to drain it all. Tilt the sled, wait an hour and all the crud will settle to the corner, then siphon off the bad stuff. Add seafoam and go.

 

[grizztracks]

The fuel is lighter than water or ethanol so it will not settle to the bottom. If the fuel is over 30 days old and was never treated with a fuel stabilizer there is a good chance that it has gone trough a phase separation which requires replacing the gas with fresh fuel. Even if you siphon the water and ethanol off of the bottom the remaining fuel's octane has been altered. There is no good or safe fuel additive to correct phase separation so the best thing to do is replace it before it causes severe damage to the engine.

http://www.fuel-testers.com/remove_water_gas.html

 

[srvfan]

Bypass your tors as stated in the manual and try it again I vote for tors issue