Top end power on kdx 200

[JZ05220r]

As some may know I struggled with headgasket issues for awhile. I ended up finding a new kdx 200 cylinder and swapped all my kips parts over. Just got it out for the first time today. It feels very good and surprised me with how responsive it was off the bottom to midrange. I noticed the bike wasn’t smoking very much and when at wot it seemed to pull sorta flat. I could definitely feel the kips start to open and it made great power during that transition but once totally pinned it seemed borderline flat. The lack of smoke worried me abit. There is some oil starting to build around the ID of the end cap. I have the airbox lid on with the rb carb set up with jets within the typical baseline for the kdx 200. I also am using a pro circuit platinum 2 pipe. I’m not hearing any pinging indicating a lean condition. Obviously I went with the “ride it hard break in” but I gave it a good bit to warm up while varying the rpm’s. I already pretty much know the kind of responses I will get here but thought I’d share this anyways. I’ll recheck the kips operation though I really doubt that’s an issue cause I can feel the power kick in for when it opens for sure. Everything kips related was triple checked on assembly.

[JZ05220r]

To update this I just realized the timing is advanced between the mid mark full advance mark on the stator plate. That’s gotta be a contributing factor.

[bufftester]

On 2Ts advancing the timing effectively moves the power band down making it feel flat on top as RPMs increase in the KIPS activation range. Try setting your timing to the stock position without changing anything else and then ride it and see how it feels.

[JZ05220r]

On 2Ts advancing the timing effectively moves the power band down making it feel flat on top as RPMs increase in the KIPS activation range. Try setting your timing to the stock position without changing anything else and then ride it and see how it feels.

Changed it back. Have you ever experienced this when playing with timing? Also I’m running the platinum 2 pipe after exclusively using the desert pipe since right after I got the bike so that might be a factor. Only rode the bike for like 15 minutes after changing it. Didn’t really focus too hard on it but seemed better. KIPs is still definitely opening as I can feel the rush of power right out of the midrange. I’ll have to hold the throttle wide open for a few seconds to really see if there is a difference. I took my sweet time and really checked over absolutely everything over the winter. Everything kips wise is timed up perfectly. Oh yea.. before first start I did noticed it kicking back twice before it turned over, another thing that I believe was ignition timing related. Thanks for your response

[JZ05220r]

To update this, the bike feels a lot better. (I think it was combination of the rings still seating and the timing) I really like the way it’s running. Just gotta sort out an idle issue I’m experiencing. I have dealt with the problem on both kdx’s. Switching to a different gas station helped my 1991 200 to the point where it idled pretty much flawlessly and steady. Still using that gas station on both bikes. Regardless I’m still getting the dipping idle after sitting for a bit with the rpm’s hanging a bit after throttle blips.

[bufftester]

make sure you set your float level to 18mm instead of the stock 16, that should help with that little bobble

[JZ05220r]

I rechecked float height and got between 17 and 18 but most importantly the fuel level is about 1mm above the mating surface using the clear tube.

[JZ05220r]

I put a bit over an hour on the bike so far. It’s starting to smoke more now with some spooge starting to develop. It’s somewhat interesting to me. It’s shown me firsthand that the majority of smoke produced by a 2 stroke is related to the amount unburnt oil residue/build up inside the pipe. Makes sense when I hear that spooge out the silencer can’t usually be eliminated safely as their is a need for some unburnt oil, my goal is to find a safe balance of exhaust/exhaust port temps and amount of unburnt oil based on premix ratios and oil choice…. Does seem to have some intermittent stumble partial throttle due to my current set up loading up when I lug the bike around. I’m switching from the Maxima premium 2 oil at 40:1 on this first tank to 32:1 using Kawasakis 2 stroke oil. I have read good things thing about it. Not trying to say “oh, I have a Kawasaki so I’ll use Kawasaki oil!”, but it was attractive to me after reading the specs and talking with jaguar about it he explained how it’s very unique in a good way to have a synthetic blend that doesn’t consist of group 1 oil. Specs show group 2/petroleum oils mixed with group 4/synthetic. The Kawasaki oil also has a lower flash point at 255 degrees vs the maxima at 280 degrees. As for the idle I’ll wait till my switch up on oil and ratio first then mess with jetting.

[KDXGarage]

I wouldn't worry about how well it idles, but how well it goes. :-)

Congratulations on the new cylinder and getting things much better sorted.

[bufftester]

and keep in mind that any changes to mix ratios will drive jetting changes

[JZ05220r]

and keep in mind that any changes to mix ratios will drive jetting changes

Yes absolutely, I feel the bike is already running rich especially based on the stumble I feel when I’m light on the throttle off the bottom acceleration. Wick the throttle open fast from any position and there is no stumbles. I have always stayed away from a leaner mixture of 32:1 thinking it will just spooge and smoke more. After all the time and money I have put into the bike I’ll feel more comfortable with the extra oil once I get the jetting sorted and I bet there will be less excess oil/spooge than my current baseline carb settings. I’ll have to wait and see though, I might be wrong.

[JZ05220r]

I wouldn't worry about how well it idles, but how well it goes. :-)

Congratulations on the new cylinder and getting things much better sorted.

Thank you! I would only be worried about an air leak somewhere on the paper gaskets on the top end causing the idle to hang slightly but I brushed blue hylomar on all paper gaskets and torqued every single bolt to spec. The stuff isn’t as messy as I would’ve thought after removing a few gaskets when I went to double check some things, I had some spare gaskets that I replaced the ones I wasted while double checking as well. The hylomar doesn’t dry but for the most part clings to the paper gaskets and doesn’t really remain on the aluminum when disassembling. I’m confident I couldn’t have done a better job assembling the top end.