Boxerworks.com

Sibbo wrote:What is this carb ? I don't recognise it .

Freakin expensive.

holy crap... i was amazed for the first few seconds... but when i saw the gastank flip, i think i flipped!

WOW. Love the rear set plates too. Very well done.

Garnet wrote:

Sibbo wrote:What is this carb ? I don't recognise it .

Freakin expensive.

http://keihincarbs.com/special/FCR39XR400/gate.html Probably these .

Single plugged? Why not dual with all the other expense?
Why did he change valve covers back and forth?

So many questions.

mattcfish wrote:Single plugged? Why not dual with all the other expense?

There is a school of thought developing that dual plugging has it's bigest benefits at lower RPMs and diminishing returns to the point that at 7000 ish there is no need for a second flame front. The theroy is that 2 flame fronts make the ignition happen faster in time. As revs increase the combustion event happens faster anyway to the point that it can't happen any faster. This is a gross over simplification but sorta the jist of what I've read recently.

I'm sure the bike has some fancy ignition that makes one big huge spark. Again my asumption.

Garnet wrote:

mattcfish wrote:Single plugged? Why not dual with all the other expense?

There is a school of thought developing that dual plugging has it's bigest benefits at lower RPMs and diminishing returns to the point that at 7000 ish there is no need for a second flame front. The theroy is that 2 flame fronts make the ignition happen faster in time. As revs increase the combustion event happens faster anyway to the point that it can't happen any faster. This is a gross over simplification but sorta the jist of what I've read recently.

I'm sure the bike has some fancy ignition that makes one big huge spark. Again my asumption.

Yah, I've heard that about high RPM's as well. I would like to know what kind of ignition the racers use. What sort of advance curve works on a high RPM airhead? It seems to idle fine. From the movie it looks like it's cam driven, but the ignition is unrecognizable. What sort of charging system is it? I can't see much of an alternator.

Race bikes don't need no charging system.

Tim Shepherd wrote:Race bikes don't need no charging system.

oops
Depends how far they wonna race.

I will bet that, given the way the Ritmo boxer REVS –
The crank is a mere ghost of it's former (stock) self
and that the counterweights are just a memory.