main jet way too rich for 416

[YZROOSTINYA]

i had a 170 main in and went down to a 162 and i am still too rich. it pulled so much nicer up top because i was really rich before

i am going to go to a 158 to see how that does

some of you should check your jetting cause you are prob rich if you were where i was at (170)

my plug is black and it is 15 degrees out.

[HOT-ROD]

i use a 168 with my 39 fcr . i have a 11;1 416 . i also run 117 and 93 octane mixed 50 / 50

[QuadRacer041]

wow, i guess when they say ever bike is differnt its true, when i had my 400ex i had a totally stock motor with just a k&n filter, no air box lid, and a full lrd exhaust. i was running 175 main, and my bike was running great all the way through, its weird how u having a 416 kit and you need a smaller jet,,:confused:

[YZROOSTINYA]

stock carb no choke, 42 pilot, 2 3/4 turns out air screw, 4 clip down on needle. 162 now going to a 158, scott from pro fab said no higher than a 155 but i am gonna try a 158 first as it is really cold out. i have a K&N and 6 holes in my lid without the filters, just the uni vent holes. i am gonna put in more holes soon

[Sparks425Ex]

Dang. I have a Bills Shorty Slip ON, No Air Box Lid and K and N filter with Snorkle removed and I was running a 158 and It was perfect.

Now I am almost up to a 170 after My engine got done.

Prior to getting all the little probs with the motor worked out or fixed the ole 440 was running on the edge with a 162MJ.

Temp and altitude make a big diff also.


What works great on a cold afternoon here in NJ has been way rich up in PA, so you never know.

416 with XRcam...Full exhaust, lid on.. 155 main and it's too rich right now..:(

[Steve-o 400EX]

stock motor, no choke, wb e-series, sparks filter and i got a 42 pilot with a 152 main. I think i still might be a little rich. I had a 160 and it would bog when i was wide open, now it really rips.

[Str8Wicked]

That seems small to me considering I have only a CT slip on, open airbox, k&N... I'm running a 165 right now which CT Racing recommended and was perfect just like they said.

[YZROOSTINYA]

i had it almost perfect down here but up at tower its about 10 degrees colder and prob 2-3k higher in elevation, maybe thats it?????

but its black with a 162 do i am going to a 158. we'll see

i ride it wide open alot too?????

[Str8Wicked]

Mine are usually a bit black but as long as they don't look roasted than I don't mind....

[Sparks425Ex]

Isn't it true that Plug checks aren;t always accurate?

Originally posted by Nacs425ex
Isn't it true that Plug checks aren;t always accurate?

YEs that's true somewhat do to all the additives in gas these days. No need in doin plug checks,,your motor is tellin ya what it lacks or what it needs you just have to listen to it..:D

My quad normally says.....Keep the hamma down, Keep the hamma down, Keep the hamma down, Keep the hamma down, Keep the hamma down, Keep the hamma down, Keep the hamma down, Keep the hamma down, Keep the hamma down, Keep the hamma down:devil

[YZROOSTINYA]

well when it fouls out and you cant start it, mine says


RICH RICH RICH RICH RICH RICH

[YZROOSTINYA]

should I go back to a dpr8z in the winter? over the dpr9z that is

Run the 8 plug,,if honda wanted you to run a 9 that's what they would have shipped them with from the factory..I run an 8 now and always will...I haven't fouled a plug in over 2 years..even if it's 5 degree's out and the motor oil is thicker than 4month old milk...:eek:

[400ex99]

i have wb e series; k&n filter with lid off; choke removed; 416 je 10.8:1; hotcam stg II; i run 42pj; clip lowered to 4th position; started out with 170 main jet, ran good, but not much differance in performance, went down to 160 main, no differance, may drop mj lower checking plug. performace didnt improve like i thought, still troubleshooting, timing is right also, any suggestions?
:confused:

[YZROOSTINYA]

mine has a very noticable diff especially when climbing and the mid to upper r's.

RICO

take a look at the manual - long extend high rpm calls for dpr9Z, THATS ME, also MANY engine builders suggest it, keeps the head about 5 degrees cooler(so i hear)

[YZROOSTINYA]

also my honda did not come with a 416 or a stage 2 cam:devil

if it did i wouldn't be on this board, wait yes i would!!!:blah

So PA has trails that allows you to wind 5th gear out for long periods of time??? I run in high RPM;s for long times too but not that long like a desert racer would..which is what the manual is pointing out..yes I ride the piss outa my quad,,but putting a 9 plug in,,I don't ride that long in high RPMS.. Do you desert race in PA???;)

Sounds like it might keep the engine cooler but it sounds like it also causes more fouled plugs too...:confused:

[jb400exxx]

i see what rico's saying. i kinda agree.

what part of the plug do u look at to ckeck color? and it should look like a light chocolate color right? i think my 400ex is running good. i have the mods in my sig with a 42pj, needle lowered one notch, and a 165MJ. if i'm runin a 165, should i got up to a 170 when i do my 416 with hotcams stage II, and je 11:1 piston?

[YZROOSTINYA]

i just figured with a 100% humidity 100 degrees and air cooling along with higher compression and a more aggressive cam, no dis aint no baja but hot it gets yes.

i never fouled a plug before and after talking to a few respected engine builders that was what they suggested, i will try a 8 and see what happens

i understand and fully agree with you, but i heard diff and tried it out.

[YZROOSTINYA]

down at the bottom of the insultor, yes coffee color

I notice that a lot of people like to run larger main jets than they prob need. Some just think it makes them faster others maybe just are not sure how to get it tight and fell safer running rich.

There are a couple probs with this. One is that your motor will not produe peak hp if its either too lean or too rich. another is that most of your ridding is at 1/4-3/4 throttle (well at least for most trail rides and tight wooded XC stuff etc) and though a fair amount is WOT many seem only to address the main jet or WOT.

Its gets even more confusing when you get it right on one circuit and its still rich someplace else. Gotta love this stuff.


And for the 9 plug: I have run them in the hotter temps when I know I will be "hammering it" more often than normal on long straights or fire roads etc. It does seem to make a diff and the motor doesnt seem to heat up as much.

But YZ if you went to the 8 and opened up the intake a little you would prob be closer at least till the temps rise a little.

[YZROOSTINYA]

I dont want to run rich if i dont need too, it just gives me less milage to the tank and makes me run ****ty, i just thought i need to be that high because when i checked the plug earlier it was tan, gues i wasn't wide open long enough.

thanks fellas

and i did make adjustments other than the main and they seem to be ok where they are at

[K_Fulk]

I'm runnin a 155 with a 40 pilot on my stock carb. And i played with the airscrew.
And when i had my motor rebuilt in september my engine builder said it was still too rich. Close but still rich