anyone put a dyno jet kit in a 400ex question

[chrisc]

this may seem like a dumb question , but the instructions say to put the washer above the e clip on the needle, If I am understanding this right you put the needle in and then put the washer on top. what good will that do , i would think it would just flop around the top of the slide , it would make more sence to put the e clip between the slid and the e clip . anyone anyonne.

[cals400ex]

you got a point. i don't use dynojets so i hope someone else will chime in. i have read that before too.

[cals400ex]

however, putting the washer under the clip will be raising the needle, making your air/fuel ratio richer.

[ewalker302]

The washer is for 1/2 needle jet increments.

If you put the washer under the clip this richens the needle jet 1/2 of a full clip position drop.

It's just another way to fine tune.

If you are dialed in with the clip where it is, just leave the washer on top of the clip. It wont hurt anything, & it will be there if you need to go adjust later.

:bandit:

[chrisc]

I put a e series slip on and k&n and got the jet kit so I am just going with the instructions. I just got done and put it under the E clip and went with the 146 jet like a lot of people here have said. i am going to try it but it seems a little rich. anyone else have this same set up and could tell me how they set thiers. Thanks

[ewalker302]

Yes I have a similar setup.

The recomendations in the kit are very broad/general.
It's always better for the engine to be a little rich than lean.

I run a Megamaxx II slipon (discs like the e series), uni, degree key, 16t, airbox lid on.

I use the DJ(146) & it runs fine with the DJ needle in the stock position I do plan to raise the needle at least 1/2 pos tho.

The 155 will def be too rich.
I am working on getting a (DJ)148 and a (DJ)150 to test

I would start there (DJ)146 then try turning your air/fuel screw in-out to fine tune.

The 146 will not be too rich----the next smaller size in the DJ kit 142 is the same size as the stock keihin 148 main.

You should also look into changing the pilot jet to at least a 40 or 42 to aid in starting and to avoid backfiring during deceleration.

:bandit:

[chrisc]

my idle jet is already changed (I drilled it out last year to a 42MM) it starts fine. I wonder if I should just take the washer out from under the E clip and try that?

[cals400ex]

taking the washer will actually lower the needle. this means your air/fuel ratio will be leaned out. in the colder months, you actually want a more rich air/fuel ratio than in the summer months due to the density of the air. however, if your rich now between 1/8 and 3/4 throttle, i would remove the washer. but if your rich now, the bike must run like crap in summer.

[chrisc]

Originally posted by cals400ex
taking the washer will actually lower the needle. this means your air/fuel ratio will be leaned out. in the colder months, you actually want a more rich air/fuel ratio than in the summer months due to the density of the air. however, if your rich now between 1/8 and 3/4 throttle, i would remove the washer. but if your rich now, the bike must run like crap in summer. I just put the k&n ,jet kit and exhaust on this week so I am not sure how it would run in the summer , it was all stock.

[ewalker302]

Yeah you will want to jet richer in the winter, leaner in the summer.

I may be wrong but (cold air = denser air = more Oxygen) needs more fuel.

:bandit: