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bklyn400ex
12-05-2002, 10:29 PM
what is the stock jetting??
12-05-2002, 10:33 PM
:confused: Stock Jetting is the jetting that comes with your quad from the factory
GNCC#829
12-05-2002, 10:34 PM
The pilot is a 38, I'm not sure about the main.
bklyn400ex
12-05-2002, 10:40 PM
i have a K+N filter, holes in airbox, WB r4 pipe, ground out the welds i ride in PA how can i tell if i need to rejet, it seems to run fine
GNCC#829
12-05-2002, 10:42 PM
If it pops when you let off of the throttle, it is too lean. With those mods, I would bet that you need to go up a little on the pilot and a few sizes on the main.
bklyn400ex
12-05-2002, 10:45 PM
should i buy a dynojet kit, or just get some jets from the dealer, and how can i tell when i'm perfect on the jetting, can i tell by lookin at the plug??
GNCC#829
12-05-2002, 10:50 PM
Someone else will have to answer the plug question. If you buy the dynojet kit you will have to start over, but it will have all of the jets you need. If you just buy jets, you should only have to buy a few. I have the kit, and whenever I need to rejet, I already have the right jet, I don't have to buy it, I only have to install it.
bklyn400ex
12-05-2002, 10:58 PM
which #'s should i pick up, i'm gonna go tomorrow

thanx
GNCC#829
12-05-2002, 11:03 PM
I would get a 42 pilot jet and probably the 3 or 4 sizes up from stock. Since you are guessing, see if you can return the ones you don't use. If you can't it will probably be cheaper/easier to buy the dynojet kit. But you will still need the pilot jet, that isn't in the kit.
JOEX
12-05-2002, 11:39 PM
Stock main is 148.

Joe
12-06-2002, 12:23 AM
OK a more serious reply for ya.

Deff get the larger pilot, 42 is about max (38 stk)you should need with the mods you said.

Expect to pick up a couple of main jets (about $4-$6 ea) I would think 2-4 sizes up from stk should be plenty of fuel. But its pretty cold right now so be sure you get sizes from (148 stk) 152-160.

You may have to think about raising the needle a notch also.

One thing I know is gonna come up is going "way big" on the main jet, and I just want to tell you if its running good now and you dont get more power from a one or two sizes larger main jet your not gonna get it from going even larger.

Larger jets only help performance if they are needed to work with the extra air your letting in with your mods, and remember extra fuel robs HP. Dont go so lean that you blow it up but if you can be one size up from best you are doing well.

And dont forget to jet down when the weather gets warmer.

BTW I am re-jetting my quad now also and it can be a real pain and learning experience, no matter how many times youve done it.
12-06-2002, 12:26 AM
Oh forgot this.

Dont do all the changes at once, do them one at atime.

Do the main first if you feel your loosing power on full throttle, change the pilot or needle clip if the lower throttle stuff is boggin or hesitive etc.

That way you know what to change back if it gets worse.
bklyn400ex
12-09-2002, 11:56 AM
thanx for the info, i brought my bike to the dealer, i showed them the plug, and they said it looked perfect, and didnt need to rejet according to the plug, should i fool with it anyway?? Another thing, i rode on saturday everything was fine, then i rode on sunday, when i went to start it it was backfiring like a bich and it also kept dying finally after about 15mins it was running ok are those signs that i need to rejet?
12-09-2002, 05:31 PM
i rode on saturday everything was fine, then i rode on sunday, when i went to start it it was backfiring like a bich and it also kept dying finally after about 15mins it was running ok are those signs that i need to rejet?

Was anything diff from sat to sun ?

When was it backfiring? (I know on sunday but full throttle or deceleration etc)

When or how was it dying?
bklyn400ex
12-09-2002, 06:55 PM
i started it by the house, it was fine, then drove 15mins to the trails, tried to start and i gave it a little gas and it was popping when i was holding the throttle and even with my thumb on the throttle, it would pop for a few seconds then just die, and i kept restarting, it took about 15mins to get it running.
12-09-2002, 08:50 PM
Hmmm that sounds strange :confused:

When you say drive to the trails were you on the quad or was it on a trailer etc?
bklyn400ex
12-09-2002, 09:26 PM
it was on a trailer.

do you like your hotcam?? i want to get a cam with all around power gains, which should i go with?