Snowmobile fuel mileage

[Jigaman]

I have lots of experience with four different 97/98 polaris indy trail touring (488cc fan cooled) snowmobiles used for ice fishing and I have a question for the sledheads on here. These sleds are used only for ice fishing and are fantastic cheap, reliable machines but they get horrible fuel mileage. Reading forums on these same sleds the norm is in the low teens for MPG when trail riding. This last weekend we had two of these sleds on Winnipeg and got 4-5 mpg for the trip which is what we normally get. It was very rough so all our miles (about 60/machine) were going about 10-18 mph. Does the slow speed kill the mileage? my sled was pulling a heavy otter but my buddies wasnt pulling anything and he didnt do much better. Thoughts???

 

[HammsRMK]

I am not sure on if the speed matters, but first thing I would check is the spark plugs. If they are black that means it is running rich and using way to much fuel. I would also check to see what jets are in it. We always went one to two sizes smaller than what is recommended although we were running in the mountains with the higher performance sleds.

 

[Captain Ahab]

Lay off the twinkies Moose;-)

 

[Jigaman]

Lay off the twinkies Moose;-)

I cant resist those exotic chips and candy Canada has to offer!!! But even the skinny guy on the same sled got horrible mileage....

 

[Mort]

I suspect was said earlier, may not have them jettted right for that altitude, a rich running sled/motorcycle will lose fuel along with not having the power it should. when I say lose fuel, that means its not burn all of it and it goes in the crankcase, may have bad plug or not hot enough plug to burn all the fuel. Couple of things to look at.

 

[stalker]

I wouldn't expect better than 10 with that machine in any conditions. Don't re jet it. All you will do is forget that you did, then go for a ride on a high barometer / cold temp day and end up with a hole in your piston.

Does it smell strong of gas? We end up using one every year for a LOW trip. Last year it took a tank to go 25 miles.

There are water traps on the carbs made from clear fuel lines. One was cracked and leaking pretty bad. Check all the fuel lines on something that old, including the one inside the tank. They get old and brittle. I have replaced all on my older machines from time to time. I still don't know why we were so stuck on the clear vinyl fuel lines on snowmobiles. I think it was so you could watch to make sure fuel was moving while trouble shooting engine issues. I've seen the one inside the tank can get mushy and fall off.

Another solution would be to trade it for a new Norseman. You wouldn't have to worry about fuel issues anymore.

 

[all4eyes]

8 to 10 mpg is about all you will get. I've had many sleds and and that seems to be the rule of thumb. I did have a 4stroke Yamaha that got around 16 to 18 mpg. Have a Polaris edge set up for ice fishing. It runs about 7 or 8 when set up with all the extra weight.

 

[Traxion]

One thing that can make a big difference when towing or even going slow is gearing down. I don't have any gear charts available, but when I was riding a lot we geared them down 3-4 teeth (enough to use the current chain) and it made a huge difference. It changes your RPM range slightly but more importantly gives much higher clutch efficiency. When you have a load and are going at low speeds that makes a difference. If you don't care about top speed at all you could get really aggressive on the gearing and go way low...which would probably require a new chain but would work great at the slow speeds. They are usually jetted fat from the factory, if you can figure out the coldest temp and lowest elevation you will be operating at you can usually jet one size smaller than what they chart says. Beyond that, you pretty much can't do much.

The Norseman is dead for 2020, as is the liquid cooled Bearcats. Arctic Cat is purging all the low sales sled models and the only thing that Survived was the Bearcat with the 570. I'd rather take a 500 Polaris fanner like he is talking about than the 570, biggest POS motor ever made. No power and horrible economy, especially in a 2 up or utility sled.

If I were purchasing an ice fishing rig it would be a Ski-Doo Tundra or Skandic. 550 if you want a fanner or a 600ACE liquid. Doo is light years ahead on utility sleds.

 

[stalker]

The Norseman is dead for 2020, as is the liquid cooled Bearcats. Arctic Cat is purging all the low sales sled models and the only thing that Survived was the Bearcat with the 570. I'd rather take a 500 Polaris fanner like he is talking about than the 570, biggest POS motor ever made. No power and horrible economy, especially in a 2 up or utility sled.

I wasn't suggesting buying a current model year. I personally would never buy a new one. I'm the guy with the 2000 440 fan cooled panther because I'm too tight to part with $8K to $12k for new one.

If you are interested in a new one, there are new non currents to be had.

That sucks that they dropped all but the 570 in touring and utility. Who would ever buy one of those. They are not the Cat's meow.

I was with a group that had a few 600 Norseman with the 2" lug 154" track. They are a fair utility machine and they still are light and nimble enough to go and play in the deep powder in the woods. I asked if they were good bare ice machine and the response was positive. They may have come with scratchers, but if they don't, it's an easy add.

I still don't agree with the main jet change. You aren't on the main jet at 15-20 mph unless you are in deep shit. I was running about 1/8 to 1/4 throttle to maintain that speed on LOW with my 440 fanner.