Ok, got it. Some will like the power "hit" , others won't. I also believe this rush of power is mis-diagnosed by some as problematic fueling - as the biggy power 6k and up makes the low/mid's seem weak..

Anyway, I agree with you that the combo of lidless, certain slipons (DG-O in your case, PC4 in mine), and proper fueling, seems to have a particularly interesting impact on the power curve. All other combos I've tried produce powerful but linear power curves.

BTW, as always, I was running the MCM when I experienced a similar power curve to yours with just the FMF slipon. I am thinking my "hit" occurred somewhere around 6k RPM. My "hit" was pronounced enough to ultimately be undesirable to me. Being an old 2 smoke guy, I didn't like it coming from the KLX. But I did have a great weekend playing with the "hit"..

When you get a chance, please let me/us know when over-rev begins..

 

Ill have to purposely check and feel for it and get back to you, but right off the top of my head Im thinking it starts to flatten out noticably around 9000.

Im surprised you experienced the hit running the MCM-- I am thinking it has more to do with the stock cam timings than anything else. Even when my bike was bone stock the power seemed to pickup noticeably at the same point. Like you said, at this point I dont believe it is a fueling issue, I think its more a function of the factory valve and ignition timing. Theres nothing wrong with it, especially for road use-- but I think that type of tuning would better serve the street than the dirt. If the MCM does what I think it will do, thats something I would be very interested in.

Both my quads, having nearly identical bore and stroke, etc. have a much smoother feeling power curve-- I visualize their curves looking a lot like the ones in your sig, while I def would not believe my KLX curve would be so smooth and gradual looking.

 

Yeah, it's certainly not a fueling issue, but you can imagine that if someone hasn't experienced a 2 stroke coming up on the pipe (which is becoming the norm.) this kind of powerband would be confusing.

I haven't asked whether you like your current powerband or not..?

Also note that I always ran DJ stuff - slide spring, needle, main jets.. So, this powerband is not exclusive to a drilled slide, stock spring, N1TC, and K jets.

I'm thinking the FMF slipons must be "tuned" for biggy scavenging, with the stock header, starting at 6-6.5k.. ( There are a lot of other things going on at this particular point - I.E. the slide has just fully uncovered the main jet, the cams are rapidly ramping up TRQ, the ignition curve went "all in" at 5K but it's augmenting the ramping of power.)

 

MCM increases TRQ and ramps the TRQ curve quicker while the increased overlap carries the TRQ throughout the RPM range.

Now, that being said, I can't PROVE it with before and after Dyno charts. This is from my personal experience along with a few years of researching..

The MCM would be totally "unleashed" with your current lidless CVK setup. I am sure you'll be overjoyed..

 

interesting discussion. I can definitely feel the same thing on my setup with the two bro's. I also just change my ignition map to mimic the 300. 5deg @ 1500 ramping up to 40deg @ 3000. Feels like I gained response/power in the mid range but still a noticeable hump at 6k or so. Probably the rpm the intake and exhaust lengths are tuned for.

 

Thats what Im thinking. Wont know for sure until I do the MCM though.

How did you alter your ignition mapping?

 

I have a paray programmable CDI installed.
KLX CDI module

 

Very interesting. Is there a reason you didnt just go with the pre-programmed Aussie timing?

I also updated my timing spreadsheet as I wasnt sure which one was the Aussie one-- it is written very strangely in the service manual. Your link cleared it up for me. The Aussie has more timing advance, similar timing to the Mojave.

 

No, I know. I was just stating that I dont think theres a problem with it (ie thats how it was designed to be). Not really saying whether I like it or not, it is what it is.

 

The reason I'm able to play with the timing is that they sent me a link cable to perform the update.

I ran for a while with the "aussie" advance curve but decided to try full advance earlier like the 250r and 300. I need more seat time but it really seems to like full advance at 3000. Im also currently running 92 octane fuel so no pinking with the extra advance, and i can run the stock map for 87. I was also running a bit rich on the pilot circuit and I think it can be leaned out a bit now with the 5deg initial advance.