re jet slip on

[400eXz]

hey guys i just got my 400ex all stock motor and everything. i might be getting a hmf slip on this week and i was wondering if i ran it without spark arrestor and stuff would i have to rejet my carb?

[B.C.#11TRX400EX]

r u talking bout the baffle in the stock muffler or the HMF pipe, cause the stock pipe without the baffle is bad for the engine it messes up the valves cause no back pressure, but if u get a slip-on its like gettin a new exhaust u have to jet it correctly for your engine to operate the right way, i would also suggest getting a new air filter like K&N, right now im in the process of getting a filter, jet kit, outerwears, and exhaust, im getting a full sparks system, i bought my filter, jet kit, and outerwears on ebay all in one buy for a $106.17 its was the best deal ive seen on those

[400eXz]

yea i am getting a slip on some time soon and i did cut out the spark arrestor on my stock pipe and you are the 4th person that has told me that it will destroy the rings. but i was talking about running it with out spark arrestor on the slip on. gonna get a air filter and maybe outerwares sometime soon.

[B.C.#11TRX400EX]

i would think a slip on would be fine just without the Spark Arrester, if u had it jetted right, if u just get a slip on for now use a 150 main jet, 38 pilot jet, the F/A Screw screwed out 3 turns, and the needle on the 3rd notch. If u get a filter and slip-on use a 152 main jet, 38 pilot jet, F/A screw screwed out 3.5 turns, and the needle on the 3rd notch. But if u take the lid off with a filter and slip-on use 158 main jet, 42 pilot jet, F/A screw screwed out 2.5 turns, and the needle on the 3rd notch. Thats wat i would recommend for ya

[finsteratv]

Originally posted by B.C.#11TRX400EX
i would think a slip on would be fine just without the Spark Arrester, if u had it jetted right, if u just get a slip on for now use a 150 main jet, 38 pilot jet, the F/A Screw screwed out 3 turns, and the needle on the 3rd notch. If u get a filter and slip-on use a 152 main jet, 38 pilot jet, F/A screw screwed out 3.5 turns, and the needle on the 3rd notch. But if u take the lid off with a filter and slip-on use 158 main jet, 42 pilot jet, F/A screw screwed out 2.5 turns, and the needle on the 3rd notch. Thats wat i would recommend for ya
spot on, but what elevation you running at?

[01boneless]

Originally posted by B.C.#11TRX400EX
i would think a slip on would be fine just without the Spark Arrester, if u had it jetted right, if u just get a slip on for now use a 150 main jet, 38 pilot jet, the F/A Screw screwed out 3 turns, and the needle on the 3rd notch. If u get a filter and slip-on use a 152 main jet, 38 pilot jet, F/A screw screwed out 3.5 turns, and the needle on the 3rd notch. But if u take the lid off with a filter and slip-on use 158 main jet, 42 pilot jet, F/A screw screwed out 2.5 turns, and the needle on the 3rd notch. Thats wat i would recommend for ya

im proud you have learned fast!!!

[B.C.#11TRX400EX]

under 5,000 and thanks ive been doing my homework

[Zakradu398]

For me with no lid, filter, and slip on I have 42 pilot 155 main and needle on 2nd notch. F/a screw 2.5 turns


Edit: I'm at 1200ft thanks for reminding me

[B.C.#11TRX400EX]

yep well it changes with the elevations of were ur at

[B.C.#11TRX400EX]

yep well it changes with the elevations of were ur at

[Baileygunns]

Why would you run 3 or 3.5 turns out on the fuel screw and not just bump to a larger pilot?

3 is the most I would do on my 450R, 3.5 I would go up on pilot...

I just picked up a 400 for my wife and was poking around/brushing up on it.

[Baileygunns]

So from the lack of response, I'm going to guess the best way to go is bump up the pilot instead of turning your fuel screw out that far...

[CJM]

Originally posted by Baileygunns
So from the lack of response, I'm going to guess the best way to go is bump up the pilot instead of turning your fuel screw out that far...

Pretty much, 40 or 42 pilot is usually whats needed for most.

[trxPOWER]

yeah, has anybody actully seen any ring damage at all from running with out baffles in the stock pipe?! i had been running myin like that for a year and when i took apart the motor it was completly fine.

[Baileygunns]

Here's another question... Are you burning up your rings and valves from lack of baffle or lack or correct jetting??

It would only make sense that if you can run a straight threw slip-on you can run a stock exhaust with no baffle... Stock exhaust with no baffle still has more restriction then a free flow slip-on, in return equaling more back pressure....

You're burning up from running lean not from lack of back pressure...