Reed cages and spacers - why?

[michael950]

OK, so I know the purpose of reeds...

What I can not figure out is what the reed cages are (rather why you would want replace stockers), and why the need for a spacer...

Anyone?

 

[Boris]

Cages hold the reed petals and spacers move the reeds away from the cases.
In some setups the reeds partially interfere or block the intake ports (VF3's in a GPR) and need to be spaced out.
Keeping them out of the air flow also made them last longer.

 

[demolition_x]

i know there are stuffers and spacers.

 

['Crockett]

Aftermarket reed cages, such as R&D's "M-16" cages are larger and thus have a higher flow rate. I run modified Kawi 750 Cages in my Yamaha's because they are slightly larger than the stock Yamaha cages.

The purpose of the reed spacer is to increase case volume and increase the turn radius into the transfer ports.

Reed stuffers increase intake tract velocity and reduce turbulence inside the reed cages..

 

[michael950]

So in some setups, there are aftermarket cages with a spacer and stuffers?

 

[Superjetjim]

So in some setups, there are aftermarket cages with a spacer and stuffers?

Correct... the stuffers focus the velocity and direction of the air, the spacers step the manifold and reeds away from the crank by about 10mm - helps with airflow into the boost ports apparently...

When I had my 62T 701 ported and bored to 753 I was told it was mandatory to have a manifold spacer.. not sure why..

Anyway - they're cheap and shiny! - that's what really matters!:Banane01:

 

[michael950]

What do the angled reed (manifold) spacers do?

Found this in Reed spacer ??, any additions?

 

[duckman1]

Correct... the stuffers focus the velocity and direction of the air, the spacers step the manifold and reeds away from the crank by about 10mm - helps with airflow into the boost ports apparently...

When I had my 62T 701 ported and bored to 753 I was told it was mandatory to have a manifold spacer.. not sure why..

Anyway - they're cheap and shiny! - that's what really matters!:Banane01:

Sounds like you had to run because someone wanted to sell you one. They are not needed in a 701 stock or big bore set-up, they actually increase intake tract length, thus giving you less throttle response. As for saving the reeds, never made any difference on any of my machines. I also asked Tim at novi, and jeff jensen who did all of team kawasaki's porting, both said they were just a waste of money on the Yamaha twins. I didn't ask about the others, every engine is different.

 

[suva]

On dirt bikes reed spacers are marketed to "increase low end power and torque"- the main thing I noticed was easier starting on my kx500 when I installed them, I was told that the spacer reduced "secondary compression " and that's why it srarted easier.

 

[egbrig]

Case compression is called "primary compression". Reed spacers move the reed petals back to aid entry into the boost port or ports and to move the petals away from the crankshaft pressure fluctuations that can eat the petal tips, they can also be used to aim the incomming charge more directly into the cases. Give Randy at WATCON a call, he has some books available that will explain everything two stroke. Reed cage stuffers keep the velocity up when the charge enters the cage. The cages area increase drastically at the entrance, which lets the incomming charge slow down (bad). The cage stuffer keeps the cross sectional area minimal until the charge passes though the cage petals. Then there are case stuffers but thats another story.
Erik

 

[SUPERTUNE]

I build all my motors with very carefully designed intake manifold set-ups using my custom CNC'ed reed spacers and stuffers with different cages and aftermarket cages, This is a way to really increase throttle response when done PROPERLY!