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if I road my sled for a coulple days,RICH would it harm the engine, I know the build up would be more on the heads,and excaust, and plugs and the little hesitations in exceleration. but can it mess anything up.Thank's Crash Dummy
 

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foul plugs maybe.
 

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Running rich probably would not be a good idea. Seeing as how mileage on sleds are bad enough as it is, it would probably be a good idea to be running stoiciometric. Running at stoich will save you money on gas, be good for the environment and give you more performance. And besides, why would you want to keep changing your plugs all the time? Running rich can also lead to excessive carbon deposits on your exhaust valves if it being a 4 stroke, but can also make too much smoke which I don't think you want to smell like rich exhaust gas after a run. Is there a reason why you want to run your machine rich or is it that there is a problem with it running rich?
 

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Running rich probably would not be a good idea. Seeing as how mileage on sleds are bad enough as it is, it would probably be a good idea to be running stoiciometric. Running at stoich will save you money on gas, be good for the environment and give you more performance. And besides, why would you want to keep changing your plugs all the time? Running rich can also lead to excessive carbon deposits on your exhaust valves if it being a 4 stroke, but can also make too much smoke which I don't think you want to smell like rich exhaust gas after a run. Is there a reason why you want to run your machine rich or is it that there is a problem with it running rich?[/b]
Just the end of season, tired of taking my carbs off and changing jets when the temps change. Crash Dummy
 

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No it wont bother as long as you dont hang around your clutch engaging rpm. just because when your running rich and you give it some your rpms can drop for a second and just chatter on the belt. I do the same at years end, temp fluctuates so much even from am/pm riding.
 

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I'm with you on this one Crash Dummy. I've replaced the pistons in my 99 670HO a couple times this season and am running safe - on the rich side. I've only noticed any difference out of the hole when it bogs a little - other than that it's running good.

Woodler
 

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if I road my sled for a coulple days,RICH would it harm the engine, I know the build up would be more on the heads,and excaust, and plugs and the little hesitations in exceleration. but can it mess anything up.Thank's Crash Dummy.


I see you recognize build up on your combustion chambers, plugs, and exhaust valves as well as the exhaust ports if running rich for quite a time. However, not just you but anyone else, have you ever thought about the carbon as well as the unburned oil building up in your pipe(s)? If you don't clean all of this out of your pipe(s), you are decreasing the pipes internal volume changing the soundwaves(air) pressures reverberating and changing the back pressures. All the while decreasing your engines power out put.
I would also think that by running rich ( i am guessing ), you would be leaning out your motor via the air/fuel to oil mix ratio ultimately using less oil to air/fuel mix.
I don't think you would be harming much but you never have said HOW rich you were running.
Again, I'm just guessing.
 

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if I road my sled for a coulple days,RICH would it harm the engine, I know the build up would be more on the heads,and excaust, and plugs and the little hesitations in exceleration. but can it mess anything up.Thank's Crash Dummy.
I see you recognize build up on your combustion chambers, plugs, and exhaust valves as well as the exhaust ports if running rich for quite a time. However, not just you but anyone else, have you ever thought about the carbon as well as the unburned oil building up in your pipe(s)? If you don't clean all of this out of your pipe(s), you are decreasing the pipes internal volume changing the soundwaves(air) pressures reverberating and changing the back pressures. All the while decreasing your engines power out put.
I would also think that by running rich ( i am guessing ), you would be leaning out your motor via the air/fuel to oil mix ratio ultimately using less oil to air/fuel mix.
I don't think you would be harming much but you never have said HOW rich you were running.
Again, I'm just guessing.[/b]
Running rich on an injected sled won't reduce the oil amount. The oil pump pumps a specific amount of oil per Cyl Revolution, not in relation to the jet size. On a Pre-mix sled, yes, more oil takes up more volume, less volume for fuel. Jets flow Volume, so more oil, leaner fuel
 

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Running rich on an injected sled won't reduce the oil amount. The oil pump pumps a specific amount of oil per Cyl Revolution, not in relation to the jet size. On a Pre-mix sled, yes, more oil takes up more volume, less volume for fuel. Jets flow Volume, so more oil, leaner fuel[/b]
Okay, the sled isn't going to pump in more oil, he didn't say that he was running rich on oil. However if you fatten it up with a larger jet that would mean there is more fuel than is required not more oil, right? Would this engine be running fat on fuel and leaner on oil, because you would need to increase the oil output to keep it at the same fuel/oil mix ratio?
 

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Just the end of season, tired of taking my carbs off and changing jets when the temps change. Crash Dummy[/b]
It just may be easier to loosen off the bowl cap on the carburetor and change the jet inside the cap. It may be a 17mm or 11/16" socket to remove the cap on the float bowl and probably a 1/4" socket to remove the jet. That would be a whole lot easier than to remove the entire carburetor. Hope this helped.
 

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Discussion Starter #11
It just may be easier to loosen off the bowl cap on the carburetor and change the jet inside the cap. It may be a 17mm or 11/16" socket to remove the cap on the float bowl and probably a 1/4" socket to remove the jet. That would be a whole lot easier than to remove the entire carburetor. Hope this helped.[/b]
Im running 310 on both carbs, stock is 310 pto, 290 mag. i put a 310 on the mag side to stop it from running lean in 0 degrees, (when i was wide open throtle), and when it's warm (35/40 degrees) it has a hesitation. i know i can drop a size when it gets warm, but then the next day its 0 degrees agian, got to change agian. and i do notice a thicker coat of burn on the plugs( running rich now for 3 days) dont look good very thick deposets on the electrode, and like you guys said about it in my excaust im shure it's fouled out two, i realy did not think running rich like i did, would harm anything but i apsolotely dont like cake on my plugs, so im going to keep up on the jetting and temps from now on. as a matter of fact right now its cold as heck and droppin in wisconsin and i just drove my sled and it should be running crisp whith the cold air, but its not, i belive i need to take it on the trail and clear the fould excaust because it dose sound like its wet in there and my silencer is not fireing the right sound. (thanks for the schooling on the excaust i have a mini poket bike that you have to clean the excaust for it to run good did not think my mxz was the same but there both TWO STROKE)CRASH DUMMY
 
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