Great! Not another Jetting Thread lol

[ben300]

looking for a little input here guys. I sent the 400 out over the winter to get rebuilt. went from stock internals/hmf sport slip on/open air box/jetted, to stock bore 11:1 wiseco/stg2 hotcam/crf timing chain/new valvetrain/same slip on/open air box/header weld ground..

what im asking about is a good jetting to break her in at. its been super ****ing miserably cold here in western PA the past two months, so the only time the bike has been fired up was at my builders. He fired it up, let it warm up a minute or two, and then took it down his drive way and back (not really getting into the throttle much, probably 100-150 yards) and it was fired up to get up into my truck bed. So its not really broke in yet.


So currerently, we are gonna have a heat wave today, and its gonna be over 50 degrees!!!!:eek::devil: so im gonna fire it up and bang it through some gears going down the road and back a few times. When i sent it to the builder, i was running a 178 main, 40 pilot, and 2.5 turns on the F/A screw (its an 05 so with the stock carb i cant adjst the needle clip). What i wanna know, is this jetting fine to fire her up and runner her for about 10-15 minutes, or should i bump up to a 180+?

Im not really looking to tune the carb today. just looking to get make sure the rings seat and everything is ok. i know the jets-r-dbags.com method and i did that this past summer and i could maybe get it to start a stumble at WOT with a 193/5 main.


What do you guys recomend?

Thanks

[ben300]

and FWIW, im between 800'-1100' elevation wise.

[Drifterboy3]

sounds way too rich to me. i was at a 155 i believe and a 42 pilot. the pilot helps with cold starts. i also removed my choke (no choke with the 42 i started it in below freezing weather)

[atvrider13]

sounds way too rich to me. i was at a 155 i believe and a 42 pilot. the pilot helps with cold starts. i also removed my choke (no choke with the 42 i started it in below freezing weather)155 way to lean with an open airbox!!!

[cheater13]

Go to jetsrus.com and read about the Jetting 101. It helped me out a good bit.

[2001400exrida]

155 way to lean with an open airbox!!!

if all you're running is an open lid and slip on a 155 is fine. however ben is running many more mods than an open airbox so he does need a bigger jet.

Ben i'd shoot for a 178 or 180. I run a 178 on my 426, 11:1, S2HC, ground welds, piped, lid off

Also definitely get yourself an adjustable needle, there is a good chance that with your mods now you will need to adjust that needle setting.

[ben300]

if all you're running is an open lid and slip on a 155 is fine. however ben is running many more mods than an open airbox so he does need a bigger jet.

Ben i'd shoot for a 178 or 180. I run a 178 on my 426, 11:1, S2HC, ground welds, piped, lid off

Also definitely get yourself an adjustable needle, there is a good chance that with your mods now you will need to adjust that needle setting.



ya thats what i was thinking. im gonna actually probably switch to a 04-05 450r carb.


so i ran it for maybe 5 minutes total. i have a 175 main jet in and i definitely need to step the pilot up to a 42 from a 40, and i need to hit about 180 on the main because it was definitely lean. I also need to get some better gas in it cause once it heated up, it got like a knock noise that i attributed to bad gas since the gas that was in the tank is several months old (september maybe?). so i only ran it for five minutes. once it warms some more up outside im gonna throw in some bigger jets, check my valves clearance, and then puse a vp110/93 50/50 blend of gas in it and then give her a go then. Ive got some other odds and ends i need to work on it without running it.

[JOHNDOE83]

It will be to rich when it wont rev out anymore from to much gas and it will stutter out like a early rev limiter, 170-180 almost any stock 400ex can take I dont care what anyone says, if you havent tryd it you dont know what your missing.

you should do like cheater suggested and go to www.jetsrus.com and read how to rejet. I would buy oem equivalent jets from 170-215 and start with 215 then work your way down "if needed"

I just jetted a Honda shadow with a 1/16 drill bit and a 60lbs wire fishing leader.....true story. Shadow has dual 115 main jets, the 1/16 was equivalent to like a 200 main jet. Runs WAY BETTER THEN EVER!!!

Anyway take a old jet and a 1/16 drill bit, try it out, you might not need to order any!

[ben300]

It will be to rich when it wont rev out anymore from to much gas and it will stutter out like a early rev limiter, 170-180 almost any stock 400ex can take I dont care what anyone says, if you havent tryd it you dont know what your missing.

you should do like cheater suggested and go to www.jetsrus.com and read how to rejet. I would buy oem equivalent jets from 170-215 and start with 215 then work your way down "if needed"

I just jetted a Honda shadow with a 1/16 drill bit and a 60lbs wire fishing leader.....true story. Shadow has dual 115 main jets, the 1/16 was equivalent to like a 200 main jet. Runs WAY BETTER THEN EVER!!!

Anyway take a old jet and a 1/16 drill bit, try it out, you might not need to order any!


ive tried the jets-r-us method and its the same exact method that i use. i have every jet made for my stock carb. im just looking for a good starting base. it currently has a 175 main in it, and one point in time last summer, i had a 190 main it it dicking around. in stock form, from 185-190, i could feel no chainge in the top end, it wouldnt totally rev out, but i think in stock form, it was getting way to much fuel at 180+. i fully expect to need in the 180-190 ball park and a 42 pilot, and like 2001400exrida said, i need to get an adjustable needle till i get a 450 carb.


thanks for all guys