So ,how do they do that ????

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Garnet
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Re: So ,how do they do that ????

Post by Garnet »

Sibbo wrote:What is this carb ? I don't recognise it .
Freakin expensive. :ugeek:
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jjwithers
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Re: So ,how do they do that ????

Post by jjwithers »

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.
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Sibbo
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Re: So ,how do they do that ????

Post by Sibbo »

Garnet wrote:
Sibbo wrote:What is this carb ? I don't recognise it .
Freakin expensive. :ugeek:
http://keihincarbs.com/special/FCR39XR400/gate.html Probably these .
"You ain't gonna learn what you don't want to know"
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mattcfish
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Re: So ,how do they do that ????

Post by mattcfish »

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

So many questions.
Bellingham, WA USA
1975 BMW R90/6
1975 BMW 2002
1971 VW Westfalia
1985 VW Vanagon
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Garnet
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Re: So ,how do they do that ????

Post by Garnet »

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.
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mattcfish
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Re: So ,how do they do that ????

Post by mattcfish »

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.
Bellingham, WA USA
1975 BMW R90/6
1975 BMW 2002
1971 VW Westfalia
1985 VW Vanagon
http://advrider.com/index.php?threads/b ... s.1074183/
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Re: What sort of charging system is it?

Post by Deleted User 62 »

Race bikes don't need no charging system.
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mattcfish
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Re: What sort of charging system is it?

Post by mattcfish »

Tim Shepherd wrote:Race bikes don't need no charging system.
oops :oops:
Depends how far they wonna race. ;)
Bellingham, WA USA
1975 BMW R90/6
1975 BMW 2002
1971 VW Westfalia
1985 VW Vanagon
http://advrider.com/index.php?threads/b ... s.1074183/
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vanzen
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Re: So ,how do they do that ????

Post by vanzen »

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.
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