I installed Barnett springs with the original clutch. It slips a little but only at WOT which I don't do much of. I might look into shimming the springs to increase the clamping force a little. Interesting that at 800' you were so rich. I run a DJ140 main jet with 2n needle position and get 65mpg all the time. Could be a little lean or rich but I can live with the mpg and it runs good.

 

I use an EBC DRC212 with Barnett spring 501-25-06043. I run Rotella 15-40 dino and it does a good job. I also remember that the 351 seemed to have a stronger vacuum signal to the carb so it did run a bit rich on jetting for the 250.

 

Yea I'll have to wait until it's broken in to see how it's reacting in the higher rpm range jetting wise, but for now I seem to be close.

I may change the oil again too ... I was running Kawi M4 mineral oil and then the last oil change I used Motul 7100 100% synthetic (before I ordered the 351 kit). I talked to Bill and he suggested non-synthetic so I picked up some Castrol GTX for the time being. I changed it twice to get the Motul out but it's still slipping pretty bad. Anyways, I ordered the 501-25-06043 springs this evening, I'll see how they work with the stock clutch. I don't mind getting a new clutch, it's all part of the fun!

Re: Stronger vacuum with the 351, I was thinking the same thing. The bike was drowning in fuel with the only changes being a single washer under the e-clip and one main jet larger, crazy.

It's going to be a balmy 7 degrees C tomorrow, I should be able to put 50-100km on it before I freeze

 

Iirc on another site planet klx a recommendation on using kx125 plates (not sure what yr) helps. I'm running that ebc clutch kit w Barnett springs and still have slippage in 4,5,6 if on the street/wfo. I was going to try to use washers to preload the springs but haven't seen anyone do that yet so I'm hesitant. But I will try the kx plates next.
Wonder if there are any compatable springs besides the Barnett replacement springs. I remember using cr500 clutch springs in a 250 (3 cr500, 3 stock oem) and that helped but lever pull was affected as well.

 

I was doing a bit more reading and found that you can use three of the springs built for our bike (# 501-25-06043 ) and three heavier #501-40-06017 springs. Supposedly the latter are 38 pound springs. Does anyone know where to find a list of Barnett's spring specs?

 

I would replace the clutch plates, IMO they retain oil and you will never get it out no matter how many times you change the oil. I would not recommend using other than standard oil, it just works, what else do you need. Going to syn oil has no advantages on the mileage/time for a dirt bike.

 

I ended up breaking one of the bolts holding the springs in today so I'm definitely ordering new clutch plates. I was pulling away from a stop sign and it went, I immediately shut it off. I got the bolt out and put three stock and three heavier springs from a YZ 2 stroke I had lying around until I get the Barnett springs and new clutch plates. I have ~130km on the BB kit now.

 

Any issues other than the clutch springs? I had the shop put heavier springs in when they replaced my clutch pack in preparation for the 351

 

No issues with the piston/cylinder at all. I did have the slide stick open in the carb today after I pinned it a bit in second. The diaphragm has expanded so I'm guessing I didn't get it perfectly back in the groove, I think it's good now.

 

Edit: Did some reading, looks like the EBC DRC works for other members here, I have ordered it.