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Ok guys had a couple requests for a write-up or how to on rejetting a carb for E85. If your expecting some long drawn out process it just isnt the case and as such you can basically follow WYO's write up on how to jet a carb, however I will throw out a few tips that may make things a little easier.

First thing to do is fill your EMPTY fuel tank with E85 and start the bike, what you will find is the bike will be running lean so you will end up bumping your pilot jet up anywhere from 5 to 10 sizes each bike will be different. Do this first and get the bike to idleing good.

Secondly it will be time to adjust your main jet for WOT now this jet will jump in size anywhere from 10 to 20 sizes in most cases and for that reason you probably wont be able to get by with the jets in a dynojet kit and will need to just order a variaty of sizes from someplace like jetsrus or whereever you want.

Lastly your needle will most likely need to be fattened up and in my experience I ended up with the needle on the highest setting lifting it out of the holder the farthest it could go. If this still isnt enough which should be then you can also add a shim to raise it a bit more. I found on my 400 that the dynojet needle from a 500 worked best as it has a little faster taper than the one for my 400.

Now here is one thing to do that is totally different when jetting for E85 instead of Gasoline and that is bumping your starter jet up from the 75 it is stock or atleast most bikes are 75 to something quite a bit larger more like a 100 or so. The reason for this is to help eliminate the hard starting issue that is inherent with E85 and cold cold winter temperatures. Keep in mind its not that the bikes wont start its just that in really cold temps they take a bit more cranking to start but a larger starter jet could help with this and also if you have a carb primer plunger on the side of the carb in the cold winter starting situations if you pump that plunger 2 or 3 times that also helps alot.

Also due to the cleaning effect of E85 I also recommend adding an inline fuel filter to your system as the tank surely has some crud in it from the regular pump gas and the ethanol is gonna break that down and wanna clean it out so having a filter will catch that prior to messing with the carb.

Benefits to look for after making the switch, smoother running engine, cooler running engine, clean spark plugs, spotless carbs, clean exhaust systems and as a really nice bonus for me, my fuel gauge has began working again.

Also if your interested in high compression pistons, advanced timing, other performance upgrades you will need not worry about your fuel as E85 really shines in high performance applications.

Also you will not be able to do plug chops as you can with gasoline and the reason for this is ethanol doesnt stain the plug like gasoline so it just doesnt work that way.
 

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nice write up Not worthy:
 

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Nice write up.

What are the bennifits of E85 in your wheeler? More power?
 

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This is a 4 plus year old post.

Not much benefit running E-85 until you increase the compression ratio and timing. BUT then you loss the ability to run pump gas. Yes the machine will run cooler, but no real power gains because a stock machine can't take advantage of the 105 plus octane. It requires 20-30% more fuel (rejet) so your losing some range per tank too.

Used to be a guy on here that ran E-85 in his mud bike without changing the fuel lines, seals, gaskets etc and reported no problems of any kind.
 
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