I took the bike out for about 90 miles today. It seems that the spring and the hole made the bike run 10x better when lugging. I also figured out that the 351 is too much torque for the clutch. I was testing it out by putting it in 5th and slowing way down then opening the throttle. It pulled hard every time. After 3 or 4 times, it spun the clutch so I had to ride more gingerly. It still seems rich in spots, but it has tons of power all around. I really wish there was another klx around here to compare side by side. I'm going to try to schedule a dyno run on Thursday so hopefully I'll have some data to share.

 

When you say "rich in spots", what exactly are you sensing? Are you still having stumbling/stammering - Which is actually aberrant slide behavior..

Actual overfueling with the CVK is denoted only by a minor "flat area" during sustained acceleration - or surges of power during sustained acceleration..The "flat area" is typically very hard to feel. The area of flatness is usually 5-7k. It is noted by a good, strong, pull, starting from 3.5-4k but this pull surges with additional power once the engine speed ''catches up'' to the overfueling and ''takes off''.. It took a dyno run to convince me that DJ150/1N was inferior to DJ144/1N (due to overfueling) as my dyno butt said otherwise..


On another note. Your dyno runs should be in 4th gear, so if your clutch is too far gone to pull 4th gear @WOT from 3.5k - 10K , you'll have to fix it before you can get good dyno data..

EDIT: nevermind, I see your edit on top post.. We need to figure out if you still have a malfunction or a slight flat spot during sustained acceleration as the engine passes through 6500 rpm..

6500 rpm is the point at which the slide achieves "full open" on a stockbore with stock spring and lift port. I have no idea if a 351 produces the same slide "operation" as a stockbore - but it would make sense that it would go full open sooner than 6500 rpm with a 351 sucking on it..


Anyway, if you still have a malfunction, that's easy.. As before, if the issue occurs at 6500 rpm, during acceleration from a WOT roll-on/snap, regardless of starting rpms ranging from 3.5k to 5K, you still likely have a stuttering/stammering malfunction. The problem area will persist in a "set" RPM range(E.G. 6500-6700 rpms) but is quicker to "work through" with a higher starting RPM and slower to work through with a lower starting RPM.. A WOT snap starting from 6000 - 7000 will produce only a few miliseconds of a "hiccup" ...

 

You hit the nail on the head with the flat spot from 5 to 7. Just doesn't have as much power right there. I may be being picky at this point. Not sure. Its good enough to hit the dyno and get actual data to York with. There is no stuttering any more.

 

Alright.. Hope your clutch is up to the task.. BTW, if you are running a synthetic oil, you'll probably help the clutch with a change to regular dino squeezins..

 

Here is the Barnett KLX clutch parts link - Kawasaki KLX250S (2006-2014) - Barnett Tool & Engineering

The $23 spring kit has been a successful "fix" on 351's when the rest of the clutch is in good shape..

 

Cool. Thanks. They're on order. I'm running real oil in the bike. 10-40 valvoline for motorcycles.

 

Got more miles on the 330, still breaking in, seems faster everyday.

I also have a flat spot about 3-5k, however, it is much less severe then when I was running a 250 on 144/1N. An interesting note..... I really only notice this flat spot when gradually accelerating (<20% throttle), and it is most prominent when the bike isnt fully warmed up. When in this flat spot, it will mostly go away if I whack open the throttle like a real man.

Not sure what that tells us... but thats all I can offer

 

I hope I haven't opened up a can of worms regarding "flat spots" .. On a KLX250 that is modded for, and running, one of the "1N" setups, the only way you can sense actual CVK 5k-6k "flat spot overfueling" is through careful repeatable testing of WOT power @ 3.5k - 9k+ , between 2 (or more) CVK setups. More pronounced and obvious "flat spots" are most certainly malfunctions. Slide stiction etc etc..

You can overfuel below 5-6K by using lower clip settings and/or bad combinations of lift port size and the DJ spring..

 

I don't think there is any misconception, its fairly obvious to my butt dyno that there is something not perfect between 3-5k now whether that's too rich/lean, too much slide, too little slide, I have no idea. I think it was pretty clear it only happens to me at part throttle operation, WOT it is not very noticeable, but it was also more pronounced when I was a 250.

Whenever my kk kit is done breaking in I'll see if I can get a dyno to get me AF ratios at part throttle operation and in this region.

 

I will also add to the collective now that my jk is broken in a bit, I have taken it to redline on a few runs, it pulls cleanly all the way to cutoff. Although it does tail off over 8500rpm, IMO to my calibrated ear/butt dyno I need a bigger jet up top and mid range is still overfueled