Spacer plate

[300rman]

ok, for a 84 R, running a spacer plate for the intake is supposed to make a difference.
what i dont know is where to put it.
Between the intake boot and the reeds, or between the reedcage and the head?
what if you ran 2 spacers, between the reeds and the intake boot?

[RedRider_AK]

It's between the reed cage and the head. All the spacer does is flattens out the flow and gives you more torque and low end. I guess 2 spacers might make more difference, but I think the change gets less noticeable the more spacer you put in.

[cr480r]

A spacer is a tuning aid to alter crankcase volume... it may or may not be a good thing...

[Rustytinhorn]

Oh Gads...
Lets not ctitisize here as I attempt to nutshell what I have learned on this subject.

If you put the spacer between the cage and block, then it will increase crankase volume. Put it inbetween carb and reed cage and it will increase inlet length and inlet volume, not crankcase volume. Whether a spacer will make a noticable performance difference, you will just ahve to try and see for yourself, especially where you have ported engine and oversize carb. Try it on both sides and see what happens, as lots of factors play into its performance.

First off, the engine speed X, at which maximum delivery ratio is produced, decreases with an increase in the ratio of the crankase clearance volume to the piston displacement.
Inlet Length:
The engine speed giving a maximum delivery ratio decreases and the maximum delivery ratio becomes gradually higher with an increase in inlet length.
The opposite is also true, the higher the rpm and larger the crankcase clearance volume, the better delivery ratio is obtained with shorter inlet ratio.
The engine speed X changes almost in inverse proportion to the square root of the clearance volume.

So in a nutshell:
larger crankcase volume=better production ratio at lower rpm's
longer inlet length=maximum delivery ratio at lower rpm's
At higher rpm's= The shorter the inlet, the more percentage of performance difference it makes, until a certain point.
There is a point were maximum delivery ratio is obtained. As the speed increases, the overall delivery ratio will drop, but having a shorter inlet will
help maintain the better ratio, even though it is still falling. Adding a spacer drops the engine speed at wich maximum delivery ratio is obtained.

Other components affecting performance at given rpm's:
Adding a bigger carb usually decreases bottom end because velocity is lost through the ports.
At low speeds (1000rpm) induction and discharge of the air are accomplished early in the inlet and scavenge periods, respectfully, due to the excessively large port areas.
Delivery ratio decreases with higher compression. (You obtain higher compression by decreasing piston displacement area. According to the above statement, increased crankcase to piston diplacement ratio will lower the the rpm at which maximum delivery ratio is produced. I believe this is true with the exception of increasing compression by replacing leaky rings.)
Pipes: "In short- the maximum delivery ratio obtained by the use of the tuned pipes increases with a decrease in clearance volume. However, the rate
of its increase falls gradually. No advantage seems to accrue from making the clearance colume excessivvely small." With two strokes you are able to use the inlet and exhuast pipes to create "ramming" affects, where you are able to actually "ram" more air/gas into the combustion chamber than what the engine would normally be capable of sucking in itself.

Disclaimer-This is my 2 cents, which I have obtained through research and tests, and that I believe in for the time being. I awknlowledge the fact that other theorys exist and that not everyone may agree with my above statement, which I concluded in a "nutshell" type format, as I dont feel like trying to defend every tiny little nit-picky detail in depth.