.....Other than my YZF450 two wheeler, I love to relax on my quad and turn the smaller dunes into a playground with my kids. After riding my Yami all summer at the local tracks, I was really dissapointed when I hopped on my KFX this Holloween out at G. I had ridden my KFX all last year too. I had just forgotten about how much of a difference there was between my two machines as far as power goes.
.....My KFX is paid for, and I don't want to take a 7k dive just yet, so I ordered a pipe and jet kit from http://www.hmfengineering.com.. They are calling for a 170 main! I am told the bike comes stock with a 150? And I have been reading here about using 165's & 160's and such. I know how to properly jet a 2 stroke, but clueless when it comes to a thump...
Anyone out here ever use the HMF stuff?
Thanks in advance.
Spode.

i have a z400 which we all know is the samething. i put the full hmf system on my bike and the bottom end is great the top is also good.

the stock jet in the z is a 130 hmf told me to put in a 175 jet put that was way off.
i have a 155 in there and it works great i have the pro-flow air filiter using a uni with the lid on and snorkal off. you could use a 160 or so if you took the lid off.
hope this helps.

Wow, yeah that does help. Here I am thinking 170 all this time. Couple more questions for ya if it's cool.
How did it run with the 170?
Also did you try other sizes and narrow it down to the 155?
And, how did it run with a 155 and stock air filter?
Thanks a bunch.
-Spode.

I have an HMF and I was using a 167.5 main on my Predator

when i had my Z i ran the Yoshi pipe with the Alba adapter(no lid/snorkel) and K&N....with a 155 mikuni mainjet.....

Id guess you will be somewhere bewtween 155-165....probably lower than 165

My local hole in the wall Kawi dealer had a 155 in stock. I am going to give it a shot. Thanks a bunch guys!
-Spode.