2006-newer Carb tip

[puTTs]

I finally had some time to mess around with my GFs 2006 250ex. We bought it brand new and it never ran quite right, eratic idle, sometimes stumbling, popping on decel, and the plug always showing a bad lean condition(white/light gray). So i pulled the carb off and found it had no needle adjustment(without shimming), 95 main jet, 42 pilot jet, and an air bleed that needs some fancy tool to adjust.

So I put in a 97 main, and left the 42 pilot. Used a small flat head screw driver to get the air bleed out, not fun. Took a grinder with a cut off wheel and notched the air bleed adjuster so a normal flat head screw driver can turn it with the carb on. I had a small junk flat head screw driver I cut down to about 2 inches so it would fit up in to adjust the air bleed with the carb on and engine running. I found that at 1.5 turns or less it ran bad(stock was 1 turn out) and at 5.5 turns or more it ran bad so I went in the middle with 3.5 turns.

This thing runs 10x better then it ever has. There is zero popping on decel. It idles dead smooth, it can idle for ten minutes straight with out one miss fire or change in rpm. Zero stuttering at any where in the rpm range. It feels so alive compared to what it was. Cold start I keep it choked for about 10 seconds feathering the throttle, then open the choke fully and it will idle perfect from there on. That was in 40 degree weather this morning. After a little riding I checked the plug, it looks much better but still a bit on the lean side I would think a 98 main would be perfect rather then the 97 I put in.

Just thought I would post this for people who have problems with there stock 250ex. :)

[BERT306]

I did the same thing to the air screw, it was a PITA before!!

[hondariderdylan]

i never really had problems with the stock jetting

[puTTs]

Originally posted by hondariderdylan
i never really had problems with the stock jetting

"Just thought I would post this for people who have problems with there stock 250ex.:)"

I know a lot of people have the same problem, there's tons of post on this message board and others. My GFs had the problem as does two other guys we rode with last weekend. Your from Georgia, your thin warm oxygen less air doesn't count. :D

...no negativity intended

[ryanh250ex]

stock jetting leaves alot to be desired. Your results could have been achieved without changing the pilot jet, but the point is messing with the fuel screw and adding fuel via the main jet does make a difference.

With no choke, mine fires up after 2-3 cranks anywhere from 5 degrees to 95. And yes, I've tested it within that range.

[hondariderdylan]

Originally posted by puTTs
...no negativity intended

none taken;)

[puTTs]

I didn't change the pilot, just the upped the main to 97. Then turned the fuel screw out 2.5 more turns then stock. I started it again this morning when it was 30. I can't believe how easy it starts and purrs like a kitten now. I'm going to have to mess with my 400 now.

hondariderdylan - How are those AC Nerf bars on the 250? What size Kenda Knarly's you running? The only thing I hate about the 250 are those stock balloon tires in the rear, so spongy feeling.

[hondariderdylan]

the AC nerfs are great they just dont have that good of a fit, the throttle side bolthole on the frame didnt line up for crap, but other than that they are great, and they can take a beating

i have 20x11x9 they are pretty good tires, i was used to the stock tires with NO tread, absolutly bald so they had a little too much bite for my tastes, but when they wear some they should be good to go