mopar1rules

what are the both of you running for jetting? are you choke tubes on? are they cracked? do you have the right float bowl on the right carb?

what fmf pipes and what is the needle clip position at? so far looking a little lean.

it shouldn't, but some have experienced a little richening of the bottom end, i believe.

I meant to say: "there is no extra fuel being passed through to cool the piston, so the piston crown gets hot, thus creating it to burn THE OIL and create the carbon on the piston top." INSTEAD OF: "there is no extra fuel being passed through to cool the piston, so the piston crown gets hot, thus creating it to burn and create the carbon on the piston top."

i would start out at 230 mains and 1-1/2 turns on pilot screw. you might have to fatten up pilots to 27.5, but just try the screw first and see. if its still too lean, even with it out like only 1/2 turn, if you have to turn it in that far then jump up to the 27.5 pilots. leave the needles stock w/clip position in the middle.

i don't know about the 2 hrs run time thing. when i had my shee jetted rich, with 350 mains and 27.5 pilots and 50:1 ratio, i had a carbon circle (about half the size of the diameter of the piston), right in the middle of the piston crown. the rest of the piston, all the way around, was washed clean. it made sense, cause with the larger jets, i had more fuel passing through to wash the oil off the piston tops. i had way more than 2 hrs of run time on it and the piston top still continued to stay "washed" clean, from the extra fuel. but now i also started to think about what Bansh-eman was saying about having the piston tops get black regaurdless, due to running premix (oil & gas are mixed in gas tank, and passing through the same jets). i would be starting to think that the wash clean means rich theory, only works in oil injected (right into crankcase) environments. but then again, i was seeing the same results as the photo, even in my premix environment, so it seems to me that i goes both ways. now it also got me thinking about the rich condition/carbon buildup condition, that you speak of. when running a ratio of lets say 32:1, there should be more carbon on the piston top, then with say a 50:1 ratio, reguardless of jet size. that would be cause less fuel and more oil (in 32:1 ratio), are being passed through the jets. now i just relized something too...i think we (Bansh-eman & me) are talking about 2 different "rich" scenarios. when i mean "rich", i'm talking fuel. i think Bansh-eman is talking about oil, when he says "rich". now, going off the last statement, that would make sense why one would see the same results as photo, when changing the premix ratio of the fuel and leaving the jets alone, in a premix situation. because of less fuel and more oil (in 32:1 ratio), are being passed through the jets, versus a 50:1 ratio, where more fuel is being passed through, then oil. in both cases, there is always more fuel being passed then oil, but i think you know what i'm talking about.

we need to know current jet sizes, elevation, current mods, and riding temps. most likely you will be adjusting the pilots. for sure the mains.

yeah, you need to clarify your air filter system, need to know current jets, elevation, temps to ride in, and soo on. need to know all the current mods to the atv as well.

actually no carbon to little carbon on the piston crown, means it running rich. the extra fuel that's being passed through the cylinders, is washing the oil off the top of the pistons. there is no extra fuel being passed through to cool the piston, so the piston crown gets hot, thus creating it to burn and create the carbon on the piston top. if you have lots of carbon on the piston crown, with no wash to very little wash (like 1/8" diameter clean spots by the piston crowns edge, where it lines up with the transfers)...then you are lean. here's a link...read on: http://www.cpcracing.com/site/256083/page/196309 ....the pic to look at is halfway down.

this should get you close: 330 mains stock needle stock clip position 1-1/2 turns on pilot screw 25 or 27.5 pilots

what is the temps that you are going to be riding in? i would keep the needle clip postion in the middle, stock 25 pilots, 1-1/2 turns out on pilot screw to start with, and try starting with 300-310 mains.

this is probably it: http://www.startinglineproducts.com/catalo...p;productID=374

yeah, i forgot to specify that. i have carbon techs, so i have reed stoppers. 87bansheeguy, what kind of aftermarket reeds do you have?

you can mill .020" off the stock head no problem.

what are your riding temps? what are your plugs looking like now? can you post some wot plug pics? here's what my '98 shee is jetted to currently (mods are in my sig): 340 mains (probably dropping to 330) 25 pilots 2 or 2-1/2 turns on pilots screws stock needles w/clip in middle position

isn't the spring under the carb caps, what returns the throttle slides? i know the first year i had my shee, i put those plates in, so they would plug that hole in the slide and i never had an issue. now this year when i cleaned the carbs, i put the plate in the slide, so it doesn't cover the hole. i don't know....it worked for me both ways.

i would just mill the head .020" for now. you can always take off .010" later. i did .020" on mine w/no problems.

you can mill the stock head .020" for some more cheap low-mid power. get some carbon tech reed petals for the stock cages and notch the upper reed stopper. did this on mine, and really noticed an increase in throttle response.

if it idles great when cold and not when warm, sounds to me like a jetting issue. what pilot jets do you have, how many turns out on the pilot screws, main jets, and float height? sounds like its rich. thats why it starts and idles fine when cold, but not so well when warm. a warm motor doesn't need as much fuel to start and idle, as does a cold motor. also, do a compression test for us and post the results.

i would say the fmf fattys. those give a good all around boost. and seeing as you already have the fmf gnarly pipes, it means that you probably have the fmf power core silencers. so, to save some money on buying new different brand silencers, that would go with the new different brand pipes, you could just get the fattys and then use your current fmf silencers, and still get a little more power throughout the whole power band. just my .02

1194 is the exact same stuff as yamabond. the same company makes the 2 of them and even the ones for gm and ford. so yeah, the 1194 will work just fine.

what are your current mods? i wouldn't look into air filters for some more low end snap. you won't get that much. if you don't have pipes....that would be my first mod.

yeah, slp makes some pretty good parts for the snowmobile field. awesome pipes for the yamaha sx viper sled.

the pilot jets that are long like that, are used in the yamaha snowmobiles. i know for sure, that marshall distributing sells the correct 27.5 pilots you need. i think they only sell to dealers though.

jet kits are junk. just rejet with correct regular jets accordingly. you are more than capable of putting in the correct jets for your application. don't need some stupid $60 kit, that probably won't be exactly what you need for jets anyway. just my .02.