Carb jetting 83 250r

[dunn]

Hi guys I'm new here but have been around 3 wheelers since an early age. I just recently purchased my first 83 250r and I'm loving it. It's in good shape and runs well. It's been bored .020 over and fresh top end. The issue I'm having is when I stab the throttle 3rd on up it wants to bog. I opened up the carb and the main and slow are 130 and 50 there was a little fuel in the air tube also. I did a plug chop twice and both showed black and a little moist. That means rich and need to downsize main jet correct? What numbers do I go to? Also removed the air box lid and it made some improvement.

[dunn]

Hi guys I'm new here but have been around 3 wheelers since an early age. I just recently purchased my first 83 250r and I'm loving it. It's in good shape and runs well. It's been bored .020 over and fresh top end. The issue I'm having is when I stab the throttle 3rd on up it wants to bog. I opened up the carb and the main and slow are 130 and 50 there was a little fuel in the air tube also. I did a plug chop twice and both showed black and a little moist. That means rich and need to downsize main jet correct? What numbers do I go to? Also removed the air box lid and it made some improvement.

I've also been told to check the reeds and the float level as well that they play a role too. Any suggestions or advice would be greatly appreciated.

[350for350]

Well you know that you're on the right track. It's trial and error. I'd try a 128 main and go from there. Go in small steps, it's easy to go too far and not know it. I have a Tecate 4 with a 330 kit in it and the carb came from the engine builder. I had to go from the 340 main that came with the carb to a 430. That's alot of jets to go through! Just keep at it.

[dunn]

I have a 128 main on the way as well as a 48 and 45 slow. I'll keep at it and hopefully won't be scratching my head too much longer. Thanks for the advice!

[dunn]

I placed a 128 main and changed the reeds. I left the stock 50 slow jet in place. Ran for a bit and bogged out. Clip is 3rd down from top of needle. I adjusted the float level a little bit. But still not getting the best response from her. Should I continue going down on the main? How about the slow jet?

[350for350]

I want to start by saying that I'm no jetting expert and there's way more experienced guys here than me. With that out of the way, I think I would try a smaller slow jet. IMHO, if it won't idle, it won't be jetted completely right.If it will idle for a while and then die, you're probably close on the slow jet size. How did it run at higher rpm's with the smaller main? Did it still bog? If so, maybe try the next smaller main. Just do one step at a time though. If you do more than one, you won't know which one made the difference, either better or worse. Also, if you're not sure about it, try a new spark plug. It can make a big difference.

[dunn]

I want to start by saying that I'm no jetting expert and there's way more experienced guys here than me. With that out of the way, I think I would try a smaller slow jet. IMHO, if it won't idle, it won't be jetted completely right.If it will idle for a while and then die, you're probably close on the slow jet size. How did it run at higher rpm's with the smaller main? Did it still bog? If so, maybe try the next smaller main. Just do one step at a time though. If you do more than one, you won't know which one made the difference, either better or worse. Also, if you're not sure about it, try a new spark plug. It can make a big difference.

Dropping the slow jet size made a big difference. Went from a 50 to a 45 I have a 48 and will try it b/c there is just a small amount of hesitation at the top end. But nothing like before. Took her for a run and made much better response so I feel like I'm just about there. I would soon like to place a new exhaust system but does that mean I'll have to tune the carb again as well? Thanks for sharing advice!