Pilot screw

[yelian103]

So I've tried looking for it everywhere and can't seem to find it. I'm looking for the longer aftermarket pilot screw for a 2005+ 400ex. Trying to fine tune now with the temp change and that "D" shape oem pilot screw is a pain to get to. If anyone has a part # and a site where I can buy it that would be great. Also, if I turn it clockwise is it receiving more or less fuel/air?????Any info would help guys, Thanks.

[CJM]

They dont make one. All the longer screws you see are for FCR carbs, not keihin round slides like ours. You might be able to get an FCR type screw to work but IDK for sure.

heres what ya do to tune it.
1. Remove it and use a dremel or a hacksaw to make a slotted cut in it or buy a regular one.
2. Loosen the carb boots on both the motor and airbox.
3. turn the carb towards you
4. Turn the screw about 2.25 turns out
5. Put carb back in place
6. Test it.

Trying to do it while its running without special tools is near impossible

[yelian103]

Thank you for the quick reply. No wonder I can't find it. Yes, I've done the hacksaw thing already in hopes to be able to get in there some how but there's no way. I put it @ 2 turns out when I bought the bike in the summer(I cleaned out the carb) but now with the change in the temp it's got a little hiccup and stalls out a bit until it's completely up to temp. If I take it out to 2.5, is that leaning it out or giving more fuel? Thanks again!

[bcleveland]

Turning it to 2.5 gives you more fuel. Pretty much all 4 stroke carbs are that way. A lot of the carbs on 2 smokes are the opposite.

[CJM]

If anything if you have the stock jetting in the carb its lean anyways. They come lean from the factory.

Stock pilot is 38, change it to a 42 regardless and you will easily start up. Also change the main to a 150 while your at it.

[yelian103]

Yup, that's why I asked. I sold my 250R and bought the 400 and it's the complete opposite. Good to know. That's exactly what I've read. They come a bit on the lean side from the factory. Reliability is the reason for the swap. I found one from the original owner and even had the factory tires/manual etc.. for $1500. Had to do it. Keep in mind it's 100% stock. Do you think I should still up the pilot/main?

[CJM]

yea, upping the pilots a must and the main itself in most cases is quite lean.

The reason these quads dont like to start up when cold is the pilots too small period. Very common to go to the 42 pilot. I also prefer the main be slightly rich to account for temp changes. Ratherbe rich than lean and blow it up.

[powerbomb400]

Pro Motion makes a screwdriver that is about 12" long and has a 90°place bend on the end. You turn the handle and it turns a slotted bit at the other end. Its marked on the handle to let you know each quarter turn. I think it was 20.00. I use it on mine and my wife's 250ex since it has the upside down air/fuel screw too. I got it from Rocky Mt Atv/MC.

[kt1148]

Originally posted by yelian103
So I've tried looking for it everywhere and can't seem to find it. I'm looking for the longer aftermarket pilot screw for a 2005+ 400ex. Trying to fine tune now with the temp change and that "D" shape oem pilot screw is a pain to get to. If anyone has a part # and a site where I can buy it that would be great. Also, if I turn it clockwise is it receiving more or less fuel/air?????Any info would help guys, Thanks. This is what I used on my 400ex to replace the d-shaped screw. A lot easier to adjust since I removed my snorkel, I can do it with it running...http://worksconnection.com/details.php?id=568

[yelian103]

Originally posted by kt1148
This is what I used on my 400ex to replace the d-shaped screw. A lot easier to adjust since I removed my snorkel, I can do it with it running...http://worksconnection.com/details.php?id=568
That's exactly what I was looking for.
It doesn't specify for what bike/carb it's for though. Would this be good for an 05?

[kt1148]

I have an 07, so I'm pretty sure it will work. I don't think the carbs are any different.

[yelian103]

Just wanted to thank you guys for the tips on jetting. Bumped them up to 42 and 150. It cold starts great now with no hiccups on idle. Didn't notice too much of a difference on 3\4 to wot with the main but atleast I know I'm not as lean as I was before. Happy Thanks Giving and safe travels. Thanks again, Yelian.