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I've been riding lately in temperatures around 45 - 50 degrees and am thinking of changing my jetting to better suit the weather (still seeing ice in some of the puddles and hitting snow at higher elevations). I'm getting a little more bog than usual that I can't fix with minor fuel screw adjustments. I have an 04 250X with the JD jetting kit installed. 42 pilot, 160 main, red needle 4th clip, air box mod, baffle removed from exhaust and backfire screen removed. Pretty standard set up. Riding in Southern British Columbia (sea level - 3000') and don't expect to see temps over 55 on a regular basis for a while (couple months). I am trying to decide wether to go with the blue needle or just raising the clip on the red needle one position to the 5th spot. I'm not sure if this does the same thing or both would fix different problems. Has anyone had any experience with trying these settings, or can some of you jetting gurus lend a helping hand with this? I could just try both, but I hate trying to get at the top of my carb and playing around. Thanks.

I think the JD kit comes with a 165 main if I remember right. I don't have his chart in front of me, but I think he recommends his blue needle for temp's below (40° is it??). You could try that, or throw in the 165 main jet. I'd vote for the bigger main because it's easier to get at. Is it the right or best thing to try -- maybe not, since he's included the blue needle for coooold temps, but you might find you like the 165 main jet anyway, and still want to throw the blue needle in there to see if gets yet even better. Jetting is like that -- it's like, "oh, what a difference, that's fantastic! Now what can I do to get it even better"....

Where in the throttle is the bog???

We run the 158 and the red needle on the 5th clip at 1500 to 4000'. I would think at lower elevations you would run it there all the time.

The bog is from closed to 1/4 throttle. Just when I snap it open quickly it hesitates a little. Worse when the fuel screw is out of adjustment. When it was warmer I could adjust the fuel screw and pretty much eliminate it. But now that its colder it seems much worse and it stalls some times after a loud pop (is that decel popping?) Always at slow speeds and closed to 1/2 throttle. I had it in the 5 clip on the red needle (sorry my bad, not the 4th) and have a Boyesen APC cover installed. No o ring mod as of yet (its in the mail from James). I think I'll try the blue needle in the stock clip position like the directions say. Colder temps means your bike needs more fuel right? So with the red needle I would need to go from the 5th clip position to the 6th clip position? Is that the thinking or try the blue needle. My pilot is at 160 and I don't have to many problems at 1/2 to full throttle. I ride very technical terrain as it is and don't spend lots of time WFO. Thanks.

Agent- Honda should put you on the payroll. I would never buy another brand of bike knowing I can't get the support I have here. I couldn't imagine trying to figure out all this stuff on my own. I've been riding for 20 years on and off and I've learned more in the past year on this forum than the past 20 combined. Great members, great advice.

Hey Red...
what size pilot are you running?
have you gone to an after market pipe?
I had the same intermittent issues with my bike, crack the throttle and pop... stall. (it would happen once or twice a ride. just enough to lose a little confidence)
I went to a 45 pilot and a 162 main and found the problem gone away
I'm riding in cold weather too but have not seen the problem even at -5 (C)
Van

redrider666 wrote:The bog is from closed to 1/4 throttle. Just when I snap it open quickly it hesitates a little. Worse when the fuel screw is out of adjustment. When it was warmer I could adjust the fuel screw and pretty much eliminate it. But now that its colder it seems much worse and it stalls some times after a loud pop (is that decel popping?) Always at slow speeds and closed to 1/2 throttle. I had it in the 5 clip on the red needle (sorry my bad, not the 4th) and have a Boyesen APC cover installed. No o ring mod as of yet (its in the mail from James). I think I'll try the blue needle in the stock clip position like the directions say. Colder temps means your bike needs more fuel right? So with the red needle I would need to go from the 5th clip position to the 6th clip position? Is that the thinking or try the blue needle. My pilot is at 160 and I don't have to many problems at 1/2 to full throttle. I ride very technical terrain as it is and don't spend lots of time WFO. Thanks.

Agent- Honda should put you on the payroll. I would never buy another brand of bike knowing I can't get the support I have here. I couldn't imagine trying to figure out all this stuff on my own. I've been riding for 20 years on and off and I've learned more in the past year on this forum than the past 20 combined. Great members, great advice.

Decel popping is what you may experience when de-accelerating from speed. You just close the throttle and poppity-pop, as you coast down. If you have it jetted correctly you won't hear any of that. It's from the fuel screw and pilot combo. If the pilot is correct, you can usually cure the decel with the fuel screw. If you can't then you probably need to step up one size on the pilot, and/or block off the smog if you have it.

Your bog is "normal" for these carbs until you jet it correctly, and add the o-ring mod. Get that done and then worry about the mains if you still need to.

Joe

Tried the blue needle with the clip in the 4th position (stock). Pilot is a 42, Main is a 160. It was a little on the rich side when I started climbing up the mountain and gaining elevation. So I have decided to go back to the red, but try the clip in one lower position (6th). From what I have read this would raise the needle slightly thus allowing more fuel to flow? Hope I got that right. Not sure if this is the correct thing to do, but I am getting good at changing needles in my carb. Afraid I'm going to wear out my seat, shroud and tank bolts! hahaha

Thanks for the input guys. I guess I will have to get on that o-ring mod once it comes in the mail. Ugh. I took a look and it would appear one would have to at least lift up the subframe to get to it. Oh what fun.

Oh yeah- pipe is stock minus the baffle (all the way out) and no smog stuff since I'm up in Canada!

Good post redrider666, I've had the same things happening here in Washington when it was cold. Now that its warming up I haven't noticed any issues this week. I am a complete noob and this post was very help.

Pulled out the blue, went back to the red needle with the clip in the 5th position. Of course I put this off through our coldest months (DEC and JAN) and now the temps are hitting mid 50's all the time. I thought about trying the clip in the 6th position, but new I would be back in there in two months time and figured, why bother. It seems the o ring mod will solve most of my problems with the hesitation I get when I snap open the throttle at a dead idle. Thanks for all the help guys. Can' t wait for summer.