AP 1,2,3 mods

[yofrankie]

I checked out Von Beard's page and was wondering if I did just the AP mod #1 would it make a difference and help with my delayed throttle response. Can I do just #1 or do I have to do both? I have the problem prone 04 x. Any help appreciated.

[highmarker]

Not sure what 1,2,3 are? but just do a thick oring (not wire). The pump travel rivet mod etc are more applicable to the 40mm carbs vs our 37's. Would also add that a bog or delay when it's cold is normal. How it rides when warm is what matters.

[yofrankie]

Beard's pdf has three parts to the mod. If I use an o ring do you have recommendations in size?

Thanks

[keviwa]

I used the O rings from a spare 520 master link. Just the right size. Runs great. Have you rejetted it yet? If not, the JD jet kit will come with the correct O rings.

[yofrankie]

? I reread the pdf and it recommends 5/16 ID 7/16 OD

I am going to piecemeal this one. I'll try doing the first part and if its a fix then great , if not then I'll try #2.

Thanks for the info.

[danny28]

i just did the ap mod and before i did it i was wondering the same thing cause i saw the same article that you are reading. that article was from a 450. on the 250 you dont do the 2nd stage.just the first one. and its so simple it only takes 2 seconds once you are into the carb. i got my o ring from the jd kit so not sure what size the o ring was but thats alot easier than screwing around with wire.

[daveindenver]

? I reread the pdf and it recommends 5/16 ID 7/16 OD

I

As I recall, that is the right size o-ring. Its fairly thick and just barely fits over the screw without much, if any, stretching. I found one at a hardware store. JD will also send you a thinner one, but use the thicker. I used a twist tie to help pull the o-ring onto the AP arm and then just slid out the twist tie.

The rivet shaving in step 2 applies to a 450. All you should do is step 1. If the timing of the squirt is off, you can adjust that via the timing screw. I haven't tried that yet.

[stretzhs459]

I did the 1st step on my 250x. Hopefully I'll be able to tell a difference this weekend.

[yofrankie]

Hardware store purchase did it. I barely got a 1/2 turn to close the gap though. Hmmm. It just seems pretty finicky and makes me want to post a thread of why I dislike the 250x. I basically had to disassemble the bike from midway back just to get enough room to access the carb (all in 22 degree weather). Man I hope this fixes it b/c I don't want to do that again. Now I don't wonder why I ride and work on my 2 smoker more.?

[highmarker]

yep, those fat alum twin spar frames look trick but really suc when you need to work on the bike.

1/2 turn. you really didn't need to make that adjustment, another confusion from the 450 thread IMO.

Hardware store purchase did it. I barely got a 1/2 turn to close the gap though. Hmmm. It just seems pretty finicky and makes me want to post a thread of why I dislike the 250x. I basically had to disassemble the bike from midway back just to get enough room to access the carb (all in 22 degree weather). Man I hope this fixes it b/c I don't want to do that again. Now I don't wonder why I ride and work on my 2 smoker more.?

[yofrankie]

Well all that pissing and moaning......it was around 52 today so I fired her up with the QS already in place and the AP mod #1 complete. It really did seem to be a fix. Why would I rejet though? I notice some of you have.

[daveindenver]

The bike is generally lean as it comes from the factory. My suspicion is so that it passes California emissions. If you're jetting is ok, then no need to rejet. Many folks use a 42 pilot jet to help get rid of the bog. Some use a 45. Many fatten up the main and raise the needle especially after they open up the airbox.

Think of it this way....a bike that is jetted perfectly with the stock airbox and filter screen in and with stock exhaust, will need to be rejetted to regain the ideal air/fuel mixture if a significant change is made to the airflow through the motor. More air requires more fuel or it will be lean. The biggest change comes from opening the airbox. I've read where some people have said they didn't need to rejet after changing the pipe. Maybe they were a tad rich before. I don't know. I've got a stock pipe and don't plan to change that. I've not yet seen anything about the impact of just removing the filter screen after the air box has been previously opened, but I may try that next year. I'm guessing you'd need at least one size bigger main...key word is guessing.

[yofrankie]

Wow, with the AP mod done its like having a new bike! Its unbelievable what a difference it makes, no more cutting out over logs or in tight corners. What a kick ass day I ended up having in the woods.