shaving my head??

[billygoat500]

After making a custom reed spacer and installing boysen dual stage reeds, I am completely amazed. The tourque and power is just nuts!!  From the posts that I have read I know that boosting compression will boost low end.  I am slowly trying to build my bike into a two wheel dirt tractor.  1:flywheel weight, 2:reed spacer/reeds, 3:soon to come FMF GNARLY.
I am doing these mods separatly to see what each one does. After the pipe I am contemplating shaving the head.  This will finish my mods and my bike will be the ultimate woods machine.  How much should I shave the head and can I get a local machine shop to do it? Or should I get some 2 stroke guru to do it?
This bike is a freekin adiction!!
This site is awesome and any help would be awesome!! Thanks Guys!!

[kx666]

there is no given answer to how much you can remove. the best way to shave the head is to take a thin piece of lead (such as soder, make sure it is flux free) and shape it into an "L" shape. remove the spark plug an place the lead down into the cyil. making shure to reach the quench band. Then slowly turn the motor over. the compressed thickness of the soder will give you a base measure.

depending on the build i wouldnt recommend going down past .060" quench band (unless you know what your doing  and dont mind risking your motor).

take your head off the bike, pull the allignment pin out CAREFULLY. lay some fine sanding paper on a planning serface (could be a thick glass, at least 3/4" but i use a good planning serface made from granite.)

KEEP IN MIND, you can always remove more later. dont get too greedy. i hope this helps, PLEASE only use this a a referance if you dont feel comfortable doing somthing dont do it.

have fun turning you 2 stroke into a 4 

[kx666]

annother thing i forgot to mention, on the k5 i recomend opening up the upper powervalve ports a little when milling the head... makes it so you dont compleatly loose you top end and keeps the bike a little cooler. 
~steve

[Polar-Bus]

After making a custom reed spacer and installing boysen dual stage reeds, I am completely amazed. The tourque and power is just nuts!!  From the posts that I have read I know that boosting compression will boost low end.  I am slowly trying to build my bike into a two wheel dirt tractor.  1:flywheel weight, 2:reed spacer/reeds, 3:soon to come FMF GNARLY.
I am doing these mods separatly to see what each one does. After the pipe I am contemplating shaving the head.  This will finish my mods and my bike will be the ultimate woods machine.  How much should I shave the head and can I get a local machine shop to do it? Or should I get some 2 stroke guru to do it?
This bike is a freekin adiction!!
This site is awesome and any help would be awesome!! Thanks Guys!!

There is no need to shave your head. Shaving the head is an old skool method of raising compression. Kawasaki tunes most all stock KX500's using the .4 mm thick head gasket to run on 94 octane pump fuel. If you want more bang, all's you have to do is swap the stock h/g for p/n 11004-1187. This optional thinner gasket is .2 mm. You absolutely need to run at minimum 50/50% race fuel/pump fuel. Even better would be 100% uncut race fuel. I run 100% Cam II, and when properly jetted, you can't believe the instant, crisp brutall snap and torque my 500 has!!!

[gowen]

After making a custom reed spacer and installing boysen dual stage reeds, I am completely amazed. The tourque and power is just nuts!!  From the posts that I have read I know that boosting compression will boost low end.  I am slowly trying to build my bike into a two wheel dirt tractor.  1:flywheel weight, 2:reed spacer/reeds, 3:soon to come FMF GNARLY.
I am doing these mods separatly to see what each one does. After the pipe I am contemplating shaving the head.  This will finish my mods and my bike will be the ultimate woods machine.  How much should I shave the head and can I get a local machine shop to do it? Or should I get some 2 stroke guru to do it?
This bike is a freekin adiction!!
This site is awesome and any help would be awesome!! Thanks Guys!!

Ahh! a 4 stroke 2 stroke!!! There is no need to raise the compression on your 500. It has plenty stock, but as polarbus said.. get a thinner gasket first.. If that is not enough, then consider it and be careful. And if you want to keep power, run race fuel. As pump fuel will detonate and cause the engine to heat up prematurely and lose power.. resulting in engine troubles too.

[kx666]

oops... i forgot to mention the thinner gasket, thanks for keeping me in line typeing wile i "work" sometimes i miss things .3

keep in mind you can change the position of the jug to change you static compression.

cometric also makes a good gasket and if i remember correctly the base gasket was thinner than stock as well as the head gasket.

[Polar-Bus]

Many 2 stroke engine tuners will play with base gasket thicknesses to alter port timing, and move the peak powerband output. Generally speaking the thicker the base gasket, the later the peak powerband, the thinner, the sooner the power peaks.

[FuriouSly]

You know, I shaved my head down about 2mm off the deck with some mild porting on the backside... definately got some different airflow but I didn't really notice any significant increase in power.  My wife thought I should go back to stock... 

Sly

[Johnniespeed]

My 500 is fast enough, I am not doing that to my head ! The pictures really do help to imagine the modifications.

[billygoat500]

Thanks for tho info guys!!
My wife says that if I shave my head using FuriouSly's Meathod she's leaving! I think I'll try the base Gasket Meathod.
Do I really have to buy race fuel? Or will some high quality NOS octane boost work?  While Im in there I think I'll change my rings.They are still original.

[kx666]

Do not use octain bosters.
they usually use methyl-tertiary-butyl-ether or other alcohols that will not mix with most fuel pre-mix oils