KDX pipe/silencer jetting

[BeatKDX]

I just added a Pro-Circuit Platinum 2 pipe and 296 silencer to my 2004 KDX220. It really woke the KDX up alot. I removed the airbox lid and rejetted it. I had a few jets lieing around, so I used them. I changed the main to a 160 and raised the needle a clip. I didint have a pilot jet, so I kept that stock, but I ended up with an airscrew setting of about 1 turn out.

What is a good baseline jetting for a KDX with these mods?
Am I heading in the right direction? I think my main jet is rich, but it doesnt seem like it.

 

[m0rie]

On a stock 220 (without boring the carb out) a 160 main seems way out in left field. What main did you have in it before?

-Maurice

 

[Phil McCrackin]

Stock is (should be) 145 main, 42 pilot and middle clip position. Where are you located?? With similar mods, I'm using a 148 main, clip in second from top and stock pilot, A/S is 1 1/4 out. Like Maurice said, the 160 main may be a bit much.

 

[BeatKDX]

Actually, I just changed the jet to a 155 and it ran O.K, it seemed to pull harder off the bottom and have a more pronounced hit, but soon after, the power fell flat and nearly stalled the bike in 6th gear, it was not doing this before. Its getting cold, so I think i will leave the 155 as is, as long as it doesnt splooge or foul plugs, which is hasnt yet. Before I went to the 160, I had the stock jet in it. As far as the needle it concerned, what clip are you running at? Also, im located in Ridgefield CT, just south of Danbury...I normally ride in Unionville/Burlington however.

Thanks

 

[BeatKDX]

Ok, I forgot to include that I dropped the needle back to the stock position. Also, Just a few mintutes ago, I think I got the airscrew really set well. I think I did this right...I set the idle really low and the air screw about .5 turns out. I began to slowly turn the screw out to lean it until it made the most rpm's, and began to lean surge a little, and turned it back a bit untill it idled highest and consistently. It seemed to have really snappy throttle response.

I also removed the plug and removed the excessive carbon build up and re-gapped it, that helped alot...riding tomorrow will be great.

 

[BeatKDX]

Good news...the KDX is now officially a screamer. Turns out the KDX had the wrong plug in it, the 9 heat range. I switched to an 8 and it really lit up the powerband, such a crisp throttle response, like nothing the bike ever did before.

 

[bereal]

jetting

When you add aftermarket pipes and/or reeds you need to lean the bike out. I run a 140 main, a 40 pilot, and dropped the needle one position. My bike screams, you might wnat to try going in that direction!

Eric