Reed Block Spacers

[Mick22]

Miles off.
A common fallacy is that the decending piston creates 'pressure' in the crankcase. It's dwarfed by the pressure above the ring.

Hey Lozza can you explain what you mean by this, is it that the vacuum created above the ring draws the charge up instead of being forced up by the piston?
Do the after market reed cages for later model bikes offer any real improvements or are they just a marketing exercise?

[ChrisACT]

Miles off.
A common fallacy is that the decending piston creates 'pressure' in the crankcase. It's dwarfed by the pressure above the ring.
Case volume is a bit like a trumpet players cheeks, larger volumes have more for the pipe to 'draw' on.
Both Freaky, the Kart rules are very strict so sneaky stuff must be employed, we needed more punch off turns, got that but it lost 500rpm off the top, add spacer we had our low end punch and restored the top end rpm.

I'm pretty sure that a trumpet does not suck air out of the player's cheeks. 

But I take your point.  The resonance and shockwaves in the pipe scaveng the mixture into the chamber thus it is actually sucked into the chamber rather than being "blown" into the chamber by the piston.  Although, that only happens when the engine is "on pipe"  If the pipe isn't working, then the piston has to do more of the work.

The result is the same though.  Larger crankcase volume = slightly less cylinder pressure but a wider powerband and will rev a little harder.

[Lozza]

Sure about that Chris Yeah a shocker analogy.Remind me to email you some SAE papers.
Mick no vaccum above the ring that's below, there is much more pressure above the ring(even before the spark event) for anything to be 'forced' out the transfers from a descending piston.
NO V-Force are probably the best and cheapest bolt on HP out there.

[Freakshow]

errrrrr.