I'm still alive. I haven't done anything with the bike yet, been a little busy lately plus it's been raining when I do have time to play with the carb. I will definitely post an update with some results when I get the chance to actually ride the bike.

 

Just a quick minor update: Still haven't adjusted the jetting. By the time I got around to doing it, the upcoming winter temps were cold enough to skew the AFR readings into the proper range. Gonna wait till spring when things warm up.... or so that was the plan (still kind of is). I was at a gas station and saw what I thought was a KLX450R, I went up to the guy and it was. We started talking and turns out he was selling it due to having trouble getting it registered to be street legal (I don't know why nor am I concerned about it). I mentioned my KLX250s already being registered and possibly making a trade which he is interested in doing. I will still get it jetted properly before him taking ownership (and log the process of course). Its a bit off subject and there's no section for the 450 here, but I figured I would get an opinion from some people that have probably dealt with more bikes than I have. Has anyone ridden a KLX450R and if so how does it compare to the 250s? Is it like the 250 but bigger? How is the streetability? I know the KLX450R based off the KX450F with some minor changes so I would assume I'm going to like it better than the KLX250s I have now. I love my 250 but it seriously lacks power... there are lawn mowers with more HP than it which makes me very sad. I know I could just be like a normal person and get a different bike that does have the power.... but apparently I'm not normal. I've always liked Kawasaki and after seeing the abuse my KLX has gone through I don't have any interest in other brands. I never thought I would sell my KLX but the 450 seems like a good reason, unless someone here thinks otherwise

 

If he can't get it registered, how are U going to do it?
If your just riding offroad, 450 is more HP for sure.

 

I know they have more power, its exactly double actually. And the 2 bikes weigh the same too, so theoretically it should feel like the 250 with a crapload more HP. I've done pretty much all the reading I can about them. I was looking for insight from someone that's ridden both and can give pretty good details on how each feels compared to the other. And its not going to be just off road, there will be street riding/commuting as well. not really any highway stuff though, learned my lesson with that on the 250. I'm not worried about the reg because it has all the lights, blinkers, and correct safety stuff. DMV sucks in CT and if you don't have every single piece of info they want it can be a nightmare to get a plate for a "converted vehicle" (which includes swapped/combined vehicles). I know someone that does nothing but go to DMV and register vehicles, he'll have all the correct info to get it done. The bike does have a title so it's not like it doesn't have papers or anything like that.

 

Okay, ill jump in to the fray.

My bike has the BB351 kit, TM33/34, removed snorkel and full Barker exhaust. Jetting is #40 on the pilot, and a #142.5 on the main. Needle position began in the middle (#3) To monitor AF/Rs, im using a Dynojet wideband controller, POD200 display, and a fresh WBO2.



The wideband is mounted in a piece of exhaust pipe with 20" of extension to eliminate reversion pulses from effecting the reading. I use the setup to tune Motorcycles and ATVs frequently, and have very good results.



Now, on to my readings. All readings were taken at a locked throttle opening after the initial squirt from the AP is burnt off.

With the initial jetting, fueling at low throttle openings was acceptable. Idle was stable at 12.4:1 AFR, and I'd see 13.2-13.5:1 when slowly accelerating. A bit rich at 1/4 throttle, but overall it's not of much concern.

Once I rolled in to the throttle, the fueling quickly started to worsen. At 100% throttle, I was dipping down to 10.8:1 AFR at 8500rpms before the bike would start to break up.

I tried no air box lid, but the turbulence caused fueling to be all over the place. Using my trusty Dremel, I opened the inlet up to 1.75"x5" and reinstalled the lid.

Success! Fueling at WOT was now 12.8:1-13:1 all the way out to 10,000rpms. Going back to reevaluate part throttle cruise, I was still seeing very rich AFRs. 1/2-3/4 cruise at 6k RPMs were dipping clear down to 12:1, and causing my abysmal fuel mileage.

To correct this area, I dropped the needle one notch. Unfortunately work called, so I will test again and update my results later in the week.

 

Update after dropping the needle to notch #2.

Idle AF/R seems happiest around 12.5:1-12.8:1

1/16th to 1/4 throttle is around 14.5:1

1/4-3/4 throttle dips down to 13:1

WOT is 12.8-13:1 through the rev range.


With my testing, it seems that the needle taper is a bit too aggressive and/or the needle's diameter is too small. I may look into changing out the needle to see if I can get my cruise AF/R's up in to the 14.2-14.5:1 range in order to boost efficiency. I firmly believe that this needle is the #1 reason people are reporting drastic MPG drops when switching to the TM33/34 over the CVK carb. Rideability is fantastic, throttle response is very crisp and power is strong up through 9000RPM's. Spinning much higher than this is just making noise, as the head flow is insufficient with the 351cc big bore kit.

 

Was writing a long winded post to ya.. All about getting the WB Lambda mounted on the midpipe instead of modifying the performance of the Barker system by extending the entire system with your pipe.. The whole subject of the ports supporting 351cc in the upper range.. Got bored with it.. So.. Short and sweet:

Assuming whatever "hole" you cut in the lid is large enough to allow a significant increase in airflow ( over just the stock hole) , and If you can get WOT to stay between 12.5 and 12.8, you can yank off your "midpipe extension pipe" , the airbox lid , and feel the power of a "pretty well fueled" fully uncorked 351.. The powerband above 6500 rpm should be noticeably enhanced.

 

So today I will finally be getting back to Jetting the carb and will be starting completely over. Once I get all my data I will start a new thread pertaining to the TM36-68 since the title on this was for TM33.