Author Topic: Kawasaki Drifter 340 Non Econo-Jet Carb Jetting.  (Read 4743 times)

0 Members and 1 Guest are viewing this topic.

sparky55

  • Newbie
  • *
  • Posts: 4
Kawasaki Drifter 340 Non Econo-Jet Carb Jetting.
« on: November 17, 2018, 03:48:26 PM »
Hello I am new here. I was given a decent Kawasaki Drifter 340. The original carb ,a vm-32 econo-jet, is beyond repair. Luckily I have a carb (not econo or power jet) from another sled That I was able to install the pilot jet in (35). However I need some help with what main jet to install. The bad carb originally had a 180 main and a 120 econo-jet. The carb I installed has a 280 jet in it that causes the engine to run quite rich. I installed the 180 and it ran 100 times better but, to the spark plugs, puts me in fuel mixture territory that I would rather not be in. Could anyone tell me what main I should install? I would prefer it to be a little on the rich side, but not too much. I ride in between 40 down to 0 degrees Fahrenheit at about 1065 above sea level. Thanks! 

mswyka

  • Hero Member
  • *****
  • Posts: 1791
Re: Kawasaki Drifter 340 Non Econo-Jet Carb Jetting.
« Reply #1 on: November 17, 2018, 04:14:27 PM »
In the manual for the 1980, it  lists a 30 pilot, 200 main, and 90 econojet.  Added together that would be 320 total less your 35 pilot would be 285.  So, you must be close with 280.
Intruders:  1978, 1979, 1981 Custom (Pink)
Invaders:   1980 440
Projects:    1981 Invader 440

rminier

  • Hero Member
  • *****
  • Posts: 507
Re: Kawasaki Drifter 340 Non Econo-Jet Carb Jetting.
« Reply #2 on: November 18, 2018, 10:13:29 AM »
 I agree with mswyka.
I have a 1975 Sno Jet with a 340 fan cooled engine and a single VM-34.
 It would be very similar to the Drifter in HP and RPM and it uses a 250 main jet.

 I then looked in a John Deere manual I have had for years.
 The 340 Trailfire used the same TA-340 A engine as the Drifter, but with a regular (non power jet) VM-34carb
Here is the jetting for sea level to 4000 feet and zero degrees and above:
Main      190
pilot        30
jet needle    6F27-3
needle jet    166-06
cut away      3.0

I was surprised to see the main only 190.
 If your sled was definitely too rich with a 280, you might try around a 250, then "sneak" down from there.
Heck, the 190 may be what you need, but you need to figure out what needle jet and needle you have so you don't run too lean in the mid-range.
75 SnoJet Astro SS, 79 Kawasaki Invader 440 (two of them), 81 Scorpion Sidewinder, 82 Blizzard 9500, 83 Yamaha Vmax 540, 97 MXZ 670....and holding...for now.

sparky55

  • Newbie
  • *
  • Posts: 4
Re: Kawasaki Drifter 340 Non Econo-Jet Carb Jetting.
« Reply #3 on: November 18, 2018, 05:08:47 PM »
I kind of figured I was close as this carb came from a sled (Ski doo citation 4500) which has just a few more ccs than this one. I’ll give a 250 a shot and see. It was defiantly causing a rich bog as if I let off a little back into mid range it would clear out and run fine again. If I wot again it would eventually load up again. I killed the engine when this happened and the plugs came out jet black. I switched to the 180 jet and the plugs came out a dark gray. Regardless of throttle from about 1/2 to wot. I tried at many positions to see if I could change the needle up or down. Thanks for the advice.

mswyka

  • Hero Member
  • *****
  • Posts: 1791
Re: Kawasaki Drifter 340 Non Econo-Jet Carb Jetting.
« Reply #4 on: November 19, 2018, 06:29:51 PM »
It is possible that the throttle response may be the result of another factor.  How much do you know about this engine?  How  is the compression?  And  since Jim has not asked yet, have the crank seals been replaced?
Intruders:  1978, 1979, 1981 Custom (Pink)
Invaders:   1980 440
Projects:    1981 Invader 440

sparky55

  • Newbie
  • *
  • Posts: 4
Re: Kawasaki Drifter 340 Non Econo-Jet Carb Jetting.
« Reply #5 on: November 19, 2018, 06:57:40 PM »
I don't have a tester to try this with at the moment so it is unknown. I cant seal the spark plug hole with my thumb when I pull it over though. I replaced the crank seals when I got it. (Propane torch to the recoil hole almost immediately rose in RPM.) I changed between these two jets twice to observe the reaction and it is pretty constant.

sparky55

  • Newbie
  • *
  • Posts: 4
Re: Kawasaki Drifter 340 Non Econo-Jet Carb Jetting.
« Reply #6 on: December 02, 2018, 09:51:58 AM »
Would anyone know what the difference between BZ9ES and BR9ES is and if BR9ES works fine in this sled.

Interceptor398

  • Administrator
  • Hero Member
  • *****
  • Posts: 2057
Re: Kawasaki Drifter 340 Non Econo-Jet Carb Jetting.
« Reply #7 on: December 02, 2018, 05:49:12 PM »
Up thru 1979 Kawasaki used BR-9EV spark plugs, there are resistor style plug.  From 1980 on they used BZ-9EV plugs due to using restore type plug caps-----I think.  I've heard you need to use the correct plug for the year of your Kawasaki or they can run poorly.  Again I am not an expert on this so maybe someone else can chime in and set the record straight.

mswyka

  • Hero Member
  • *****
  • Posts: 1791
Re: Kawasaki Drifter 340 Non Econo-Jet Carb Jetting.
« Reply #8 on: December 03, 2018, 10:59:53 AM »
Would anyone know what the difference between BZ9ES and BR9ES is and if BR9ES works fine in this sled.

I don't claim to be an expert either, but we have run BR9ES in the past but have switched all our sleds to BR9EYA.  My sense is that the EYA foul less and we change them less often.
Intruders:  1978, 1979, 1981 Custom (Pink)
Invaders:   1980 440
Projects:    1981 Invader 440