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Hi, engine runs good but unfortunately it does not rev up high.
So here are the infos, bought the bike, crank seals were bad so I did rebuild the whole thing new bearings, wiseco piston, replated cylinder, Boyesen 607 reeds, FMF desert pipe with the old stock silencer and original 33mm carb. I ran the bike before tearing it down although it was winter here so did not run much. I did run it enough to notice the KIPS was not moving a bit (the pin was broken by previous owner). So after I did all this the engine started fine but I did notice it was not running well at high RPM. I had plans to jet it so no problems. Bought a kit from JD jetting and started to the recommended jetting @ 0-3000ft from the kit’s instructions which is main 155, pilot 42 and red needle at clip position #4. Put new spark plug and It does not want to rev at all when engine is cold or hot. Looking at the KIPS moving it does not rotate all the way it should but it is moving a bit. It looks like the revs are not high enough to activate it more. Or is it my problem??? I was pretty cautious assembling the KIPS with with the manual and pictures I had from disassembly. What I’ve done so far: rechecked my timing marks because it is so constant on where it stops revving I thought I messed the timing. All good. Suspected a vacuum on the intake side so I did spray WD-40. Looks ok. I did notice when the petcock valve is ON it idles a few minutes, then it revs up and dies. It runs good with the petcock on RES. I will change this old petcock. What you guys think. Silencer clogged? Too rich jetting? Engine air leak? I’ll continue my troubleshooting and keep you posted.

Being a 220, and when with the stock carb, head, and pipe, they don't rev out and sign off really early. I see you have the stock carb so not much you can do about that except really dial in your jetting. The Desert pipe is the best choice for the 220 and helps wake up the top end considerably over the stocker but the carb limits that to a degree. Is the head stock or did you have the squish corrected?

That said, double check that you installed the KIPS pawl (diagram number 16085 - they call it a gear) in alignment. Also wouldn't hurt checking on the stock silencer and making sure it is free flowing. To find and air leak on a 2T you really need to do a leak down test as there isn't a constant vacuum in a 2T but a push/pull of vacuum and pressure.

On your carb, make sure everything is up to par. Check your float level (don't follow the manual! - set at 18mm), test your jet block gasket, only use genuine Keihin jets, and get that petcock sorted. Also, how's your air filter? It's clean and not over oiled I hope.

Another thing to check, make sure all electrical connections are clean and tight and especially so on the grounds. Make sure your spark plug wire is fully seated in the coil and not burnt or loose anywhere. How is your spark plug? Make sure to run a fresh NGK BR8ES if you are not currently.

One way or another, we'll help you figure this out!

I would try the stock jetting, 145 main, 42 pilot.. your main seems very rich and also it's been mentioned on the forum make sure your reed cage isn't 180 deg off it could definitely make it run bad up top, just my thoughts

I have a 220 with a 33 and JD jetting and mine would run exactly like yours with clip 4 and a 155. Mine even stutters with a 145. Not saying you need the same jetting as my 33 (40 pilot, red #2, and a 140 main) but I would say you’re way too rich. I love the JD needles but the main jets aren’t correct for the 220.
Even my 35 carb doesn’t run right with a 155. Plug chop is good with 145.

Ok guys it was RICH! It is almost running good now!
I went to clip #2 on the needle and a 142 main jet. Fouled a plug riding slowly with the kids but she was able to give me a smile since she is now awake and made me feel like when I was 15 years old! First time on a 220 I must say it is quite different from what I remembered from the 200 I rode back then but a lot of fun to have once I’ll have it jetted right! Again thanks for the advices my friends!

That’s great to hear but now you’ve got to get your pilot jet and air screw set up. Typically you start there and then onto the needle then the main like the jetting guide here on this site describes. Read through it if you haven’t already. Having the pilot jet set right is where you’re going to get the most fun out of the 220, having that instant off idle torque. You should be able to follow the kids around as long as you want and not foul a plug.

A quick test that I use for the air screw setting is to get it fully warmed up take a few high rpm blasts to make sure it’s cleared out. This test only works if the needle and main are close to good. Then ride slow, like 5 mph in first gear. Twist the throttle wide open and back to 0 throttle as quick as you can. 1 finger on the clutch always for safety.

If it stutters it’s rich
If it bogs like it’s out of gas it’s lean
When it’s right the front wheel will pull off the ground instantly

At first make big 1/2 turn changes to the air screw to see what’s happening. Once it’s in the ballpark then you go 1/8 turns at a time.

If the pilot jet is the right size you should find that sweet spot between 1 and 2.5 turns out from lightly seated.

Just remember that the early circuits are still in use as the throttle opening goes up. Each new circuit is in addition to the previous circuits.

Thanks for the help. I have already read through the jetting guide on here and I plan on following that right after the few weeks of family vacations (with the wife = no dirt bikes involved)