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Discussion Starter #1
well I put around 100 miles on my sled this past weekend between trails and lake riding. Sled ran great but I"m getting around 3-4 mpg which is pretty crazy, any ideas? The first couple days I thought she was just "ok" on power since she is a 94. Then I found a flat run on the lake and evidently she's all top end. The power band hits at 65 and pulls nicely. With the suspension tho finding areas to let her ripe are few to none. Can I change a gear for more mid-range power and which one and where do I order one? Thanks for your help
 

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Welcome
Most get about 7-8 mpgs
Start with your plugs and piston tops, you may be over fueling as well as over oiling
 

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Discussion Starter #3
funny you say that. When I changed the spark plugs the tops of the pistons are covered in black sludge. So I can just take the tops off and clean them and put her back together?
 

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NO not at all.
If the top of the piston is completely black and no wash at the ports you would be lean.
There should be just a small clean spot at the transfer ports.
The black and gunky is your oil pump
 

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Discussion Starter #5
the black gunk I noticed was before my trip as i think of it. After my ride weekend and your reply I checked and the tops are a nice coffee color now. Carb cleaning?? and what about getting more usable power at low to midrange
 

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Getting your jetting and oil pump lined out is going to do the most
Next if you drop a tooth from the top gear the clutching and all will actually work better
Your just NOT going to get 10mpg
 

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Discussion Starter #7
won't dropping a tooth increase top end? I'd like to increase the bottom / mid range for more usable power
 

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Yes, dropping it will make it more like overdrive. The RPM will be a little less for the same speed, thus less fuel used. To get more midrange, you will use more gas at the top end. The engine will be turning faster. My two mountain sleds are this way. They are geared for pulling in deep snow. I don't get the mileage that the trail sleds get.
 

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NO Wrong way
Taking a tooth off of the top gear will Lower the ratio and allow the clutches to make a fuller shift and not have to work as hard
 

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Discussion Starter #10
KC I thought of my bicycle shifting and that makes sense now. I hope to change the gear this season yet and let you know. I believe they came stock w/ an 18 tooth and I'll go to a 17?
 

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Open it up and see what you have.
It is possible but you may have to either add one to bottom as well to make chain work?
 

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Discussion Starter #13
I've had a chance to open my gear box and I've got a 20/37 gear box. I have a 18 tooth drive gear. No clearance to go larger on the bottom gear so it seems. Can I lose a link in the chain and can a shop do that, or should I go w/ a 19 tooth?
 

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18 is too much, no you will have to buy a new smaller chain.
See about aftermarket gears and chain and get a 19 38
but look at your chain, stretch it out and lift it on its side and see how much it rainbows.
You may want to get all new?
 

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Discussion Starter #15
ok, I'm having trouble finding a 19 tooth but will keep trying. Going from a 20 to an 18 and keeping the lower 37 the same is quite a jump
 

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Discussion Starter #17
thanks for that, I couldn't find a 38 but found a 39. So I'm going w the 19/39, I'll let you know how it goes
 

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Sometimes go one up/down on either one but not 2 without buying a new chain I thought. I have never really done gearing on any sleds of mine. I just left them stock and messed with clutching.
 
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