Motor shimming?
 

Ive noticed on some of the threads that has been posted on hear about shiming such as if you run 30% then you need to have atleast 3 shims and if you are running 20% then its less so what is a simple way of knowing how to shim a motor and the amount of thickness they need to be. Cause what I belived to be right is starting to sound way wrong I just thought the less shims that you had then the more compression but from the few threads Ive seen it sounds all wrong.

you need to shim for the fuel...

it should specify in the motors manual..

most race motors now come with shimming for 25-30%

the best way to know is to get some solder bend in in an L shape stick it down the glow plug hole and turn the motor over
measure the head clearance (how smashed the solder is)
and re shim according to fuel percentage.

My motor is a Axe Rosi Mammba Evo x1 The instrucions was very vague meaning it did not mention that just said the fuel and oil content mix it is made for 30% witch I am running 30% Byrons fuel

Now could you give me the diameter of soldering to use and what the shiming should be for the amount of mash that is done to the solder Now that I have heard before with the soldering just forgot the diameter to use but did not know that the amount of mash could give you the indication of how much shim to use

you will have to search around for that as will i because i dont seem to have it bookmarked anymore.

Use 1/16" (.062) or close for solder. I prefer non flux core as you get a better measurement.

General rule is .023-.025" clearance is a good start for 30%.

thanks jimmy i have this thread bookmarked now,

.19-.22 is good for 20% right?

Uhm Yes (.019-.022) :)


.1mm = .004"


Just be careful and pay attention to plug readings.

Thanks for your help

ae rossi x1 comes shimmed for 30% should be a 3 or 30 on the top of the head button

Thanks reply sent