Jetting Help Please

[Foxrage]

Ok Heres what i have: 416 piston with 11:1 comp, Hotcam stage II, No lid, KandN Filter, Stock carb with 170 main jet and 45 pilot and 3.5 turns out and no choke< I have a Fatboy 4 complete exhaust. When at low speed you really have no throttle responce once you get up to higher rpms it hauls ***....Any suggestions....Ive tried everything except a smaller main jet.

Thanks

[cals400ex]

i would try a smaller mainjet. i would put in a keihin 162 or 165 at most. try 3.0 turns out on the fuel screw.

with that cam, you won't have a ton of power until later in the powerband. if your looking for more at lower rpms, your best bet might be to change cams.

[Foxrage]

Ok ill try that.....I know the cam is more for top but that shouldnt make it spit and sputter at low rpms? Im going to put a 165 in it and try. Thanks

[Ralph]

ummmm isnt the pilot jet low end? try a 42 pilot jet

[hondarider2006]

Originally posted by Ralph
ummmm isnt the pilot jet low end? try a 42 pilot jet


yeah man, do that. I tried a 45 and it was just to much. The 42 was perfect, and I am at like 2 turns out also.

[Foxrage]

Ive already tried all the pilot jets and 45 worked best.

[Foxrage]

I had a stock one and it was still doing it and went to a 42 and it was still doing it so i tried 45 so im thinkin a 165 main and maybe half or one turn in on the screw. Thanks

[hondarider2006]

I have a hotcam stage II in my 416, and it has plent of low end, so I don't think your cam is your problem. Have you done a plug test yet??

[Foxrage]

Not yet i was gettin ready to. But it hast fouled out yet put it smells like its gettin too much gas at low rpms. Thanks

[Ralph]

Originally posted by Foxrage
Not yet i was gettin ready to. But it hast fouled out yet put it smells like its gettin too much gas at low rpms. Thanks ]


that would be your pilot,


is your airfilter clean?

[Foxrage]

How can that be tho i had a 38 in it and the reason i went to 45 was to try to solve the problem and it didnt change much. Im going to try some things from what everyones said. Thanks for the help.

[hondarider2006]

Originally posted by Foxrage
How can that be tho i had a 38 in it and the reason i went to 45 was to try to solve the problem and it didnt change much. Im going to try some things from what everyones said. Thanks for the help.



well man, you can't go 3 1/2 turns out with a 45 pilot, I was at 1 1/2 and it was wayyy to rich. Go to a 42, 2 1/2 turns out, needle on the 3rd notch, and a 162 kehlin mj. If that doesn't work...man I have no idea.

[cals400ex]

what THROTTLE position is the problem at?? we need to look at throttle position, not low end or top end as much. for example, if your flooring it in 1st or 5th, your using primarily your mainjet. so, the low end power of 1st or the top end performance of 5th shouldn't matter as much as how far your have the throttle lever pushed in. by the way, i would go down a little bit on your mainjet.

the pilot jet shouldn't matter too much unless your bike is having a hard time ideling. i have ran 38, 40, 42, and 45 pilots. there isn't much difference. as a matter of fact, my buddy is running a very mild 406 and he runs a 45 pilot jet. we just needed to set the fuel screw to only 2.25 turns out. i run a 42 pilot jet but i am around 3 turns out.


where is the needle clip position at??

also, i have a gt thunder rev box. this advances your timing 6 degrees along with raising the rev limit. this really did make my throttle respone more crisp on my 426. i assume it is from the timing being advanced. so, this rev box or a timing key is an option for you too. but, if you have a stage 2 cam, i would really really suggest getting a rev box because that cam makes power up there.

[Foxrage]

It will idle. its just once you start giving it gas it starts to spit and sputter.

Ok say you start it up and you haul *** around the track or whatever. Whenever you slow down and ride slow like through the pits is when it will spit and sputer. Thanks

[04EXdude]

As little as a 1/4 turn of the air/fuel mixture can make a big difference. With a stock bore I run a 40pj, needle clip in 4th slot and can only go 2 turns on the screw. If I go 2 1/4, I get the symtoms your describing. It revved out nicely but if I punched it at low RPMs it cough, spit and sputter. Go with a 42pj and start at 2 1/4 turns and take it from there.

[cals400ex]

what needle clip position you at?

[Foxrage]

Im not sure whatever the dyno jet said to put it on.

Also the octane of the gas would make a difference too wouldnt it. I run 87 most of the time. I ran 94 this weekend and it seemed to get better. I might try some Cam 2 and 87 mix.

I will also try messin with the air/fuel screw a little bit more. Thanks

[plkmonster2]

Wait one minute. I saw that you said "whatever DYNOJET." There is clue #1. Dynojet jets are a lot different than keihin. on a dynojet, a 155-160 should be plenty. Also, running 11:1 compression with 87 octane? That is a no no. You should be running 92 or higher only!

[cals400ex]

yes, now that you mention dynojet, that does change things around a bit.