99 WR400 Throttle stop

i have searched this site for the past 2 hours and cant find a solid answer on how to shorten the throttle stop screw. i disconnected the grey wire and JD jetted the carb. this is really the last thing i want to do to this bike. i have seen NUMEROUS post about just getting a YZ screw instead of cutting the one i have. can anyone give me a part number as i like that idea a whole lot better! also can you tell me how the stop works? i mean i know how it works physically, the name is pretty self explanatory. what i mean is do you have to adjust it or do you just take the WR screw out and put the YZ screw all the way in? any help would be appreciated!

i thought the wr400's did not have a longer throttle stop? :smirk:

maybe not. thats what im trying to figure out. i guess ill check it when it i take the carb off whenever my new fuel adjust screw comes in lol. i did disconnect the grey wire which did make a difference.

I'm pretty sure you don't have to change your throttle stop. When you have your carb off for changing your air/fuel screw, open the throttle fully and see if your slide opens completely. Maniac

yeah ill try that. just waiting for the new fuel/air mixture screw to come in so i dont have to take it off twice lol. it had a YZ carb on this bike when i got it. seemed to run a lot harded but never consistent with it. i changed it back to a stock carb and am wondering if maybe now i should just put the YZ carb back on and try to tune out its problems. any thoughts on if the YZ carb works better? seemed to do good even though it didnt have the hot start button. at least with it the bike cranked first kick everytime. seems harder to start with the stock one on for some reason.

The throttle stop on the 400's is non-existant. You can open the beast all the way without having to change it!

Do the Eddie mod (see my post in the carb sticky) to get rid of the bog, and then rejett it. I'm not quite positive though that the JD jet kit is best. I wound up needing a 180 main jet, they only included a 170.

where did you get the 180 jet. i may need a little more on mine. it has a little loss in the mid range area.

can u give me a link to the post you are talking about? i looked but cant find it.

never mind i found it lol

i ride belox sea level (louisiana) and it is around 90 to 100 degrees here. what would you suggest i set my needle on the JD kit and what size for a main? i have is set in the center on mine now.

where did you get the 180 jet. i may need a little more on mine. it has a little loss in the mid range area.

The better dealerships will have a box of them, and they are only $4 or so each. Also JD jetting was quick to mail me one after all my dyno tuning.

I ran my bike at Albany MX Park this past Saturday and it ran like a bat out of hell, so it's definitely worth running a 180. I have the airbox lid removed though, along with a full FMF exhaust!

i ride belox sea level (louisiana) and it is around 90 to 100 degrees here. what would you suggest i set my needle on the JD kit and what size for a main? i have is set in the center on mine now.

I'm pretty sure his standard directions should be okay. If you remove the airbox lid though and have a pretty good exhaust, going up to a larger jet size may help you out!

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