TM K9

Larry Westenhaver · Joined: 11 Dec 2011 Posts: 9

Hoping I could gets some tips on tuning for a K9. I was wondering about carb settings like most common jet sizes and how to adjust it properly? New to the sport from dirtbikes and just trying to learn my new engine.

Thanks!

Steen Carstensen · Posted: Sun Dec 18, 2011 10:02 am Post subject:

Tuning any high performance 2 stroke very much depends of altitude and the local weather conditions. I would suggest you buy a good air density gauge and keep records of your progress.
Base setting for the Dellorto VHSH 30 MM is:

Emulsion tube DQ 266- 268
Needle K 22 second clip from top
Main Jets 145- 155
Idle emulsion jet B45-B50
Idle jet 60
Idle air screw 21/2 turn open

I have been using VP C12 or VP MS 98 with Motul oil at 25:1 with very good results

Larry Westenhaver · Joined: 11 Dec 2011 Posts: 9

Thanks for the help Steen. I live in California in the central vally. Would you change any of those number based on my elivation compared to BC?

Steen Carstensen · Posted: Sun Dec 18, 2011 11:59 am Post subject:

On a day where the temp is around 68 degree F barometric pressure 1025 and humidity around 65%, I would start out with an emulsion tube DQ 268 and a 155 main jet, K22 needle in P2 (second groove from the top) idle emulsion B-50, 21/2 turn out on idle screw and then work your way down on the main jet and maybe go to a DQ 267 if the midrange is flat, leave the needle in P2. Check the top of your piston for burn pattern and color and also for signs of detonation. You can google 2 stroke tuning and find lots of pictures of what the piston top should look like.

Tom Barth · Posted: Mon Dec 19, 2011 5:15 pm Post subject:

Not trying to upset the applecart here but I would like to pass along some info I have, that has given me a new set up for the KZ (ICC) carburetor.

About a year ago I switched to a set up that came from Tec Sav (the great engine tuners from France). It has worked great and I have never looked back. If you want super performance without worrying too much about main jetting try this:

DQ264 atomizer
K93 needle
CD1 inner idle
60 outer idle
130 main jet
idle screw at 2 turns

I used this set up at Super Nats and with the support from Tec Sav ended up with a 128 main jet. Temps fluctuated from middle 60's during day to lower 50's in the evening. Never changed main jet from 128.

Looked at piston & combustion chamber when I got back home. Perfect.
_________________
Tom Barth
http://www.greenflagkarting.com/

Power is good...more power is better... too much power is just right!

Steen Carstensen · Posted: Mon Dec 19, 2011 6:26 pm Post subject:

No worry Tom, you gave me the Tec Sav set up a while back, works like a charm, but thought the more conventional jetting would give Larry a bit more room for error.

Joe Ricard · Posted: Mon Dec 19, 2011 6:29 pm Post subject:

Yup when I put Tom's jet package in my Vortex RVS all I could say was Holy Crap!!! This is awesome!!!!!!!!!!
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Arrow AX-8/ Rotax Sr.

Larry Westenhaver · Joined: 11 Dec 2011 Posts: 9

Hey thanks guys.. Took my kart in this morning and the problem was detonation. Won't be until the end of the week before he gets to mine so I'm hoping to be back out by next month. I'll give him the settings you've suggested and see what we can work out.

Thanks again

Antti Kinnunen · Joined: 13 Dec 2010 Posts: 72

What fuel and what squis/chamber volume gives you detonation in what condition? I'm wondering how low I can go with euro-98 ocatane fuel and those jettings...

KZ2 rules dictate min volume 11cc if I recall, but is that a lot or not?

Tom Barth · Posted: Tue Dec 20, 2011 5:16 pm Post subject:

Larry,

The only way you would get detonation with any KZ (ICC) is have some completely wild chamber volume or ignition timing. I don't believe a KZ set to specs can detonate. Let us know what you find out.
_________________
Tom Barth
http://www.greenflagkarting.com/

Power is good...more power is better... too much power is just right!

Sebastien Levesque · Joined: 21 Jan 2013 Posts: 28

Randy Pierson · Posted: Sat Jan 26, 2013 7:42 am Post subject:

Sebastien...check your pm's

Sebastien Levesque · Joined: 21 Jan 2013 Posts: 28

Tom Barth · Posted: Wed Jan 30, 2013 8:28 am Post subject:

Please use jetting that I have suggested. It came directly from Tec Sav and works anywhere, anytime, assuming weather conditions are not excessively extreme. It works on sprint and long track. Use this jetting on any KZ make.

11 CC's is actual combustion chamber volume and is not excessive.
_________________
Tom Barth
http://www.greenflagkarting.com/

Power is good...more power is better... too much power is just right!

scot smith · Posted: Sat Feb 02, 2013 1:24 pm Post subject:

Tom, I don't have my inner idle jets in front of me but I think they all have numbers. What does a CD 1 inner coorelate to in number sized inner idle jets? What clip position are you running on the needle?