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Photos of 167 hp 2-Valve Guzzi


ALLAN

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on the anima guzzista website now the story of the engine. Great reading

in google english:

http://translate.google.com/translate?sour...5fmariani%2ehtm

 

 

The angle between the valves on that motor is one of the narrowest I've ever seen for a 2 valve motor!! The power of that motor must combine torque and horsepower to exceed even the Buell engine!! I would much enjoy seeing that bike on a racetrack!!

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The angle between the valves on that motor is one of the narrowest I've ever seen for a 2 valve motor!! The power of that motor must combine torque and horsepower to exceed even the Buell engine!! I would much enjoy seeing that bike on a racetrack!!

 

Very interesting article, if you can get past the massacred (machine) translation. Particularly interesting was the bit about improving the Guzzi's combustion dynamics with increased swirl. Absolutely follow the link even if only to scope out the pics at the bottom of the page: nice shots of sectioned cylinder head(s), displaying the water cooling galleys, the combustion chamber, etc. Notice also the details like roller lifters & rockers [i've only mentioned these like 1/2 dozen times since joining v11LM! ;)] in addition to the 106x76mm cylinders? Yowza!

 

I wonder if they'll really be making this available as a kit, like they hinted at in the interview text?

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Guest goffredo

The angle between the valves on that motor is one of the narrowest I've ever seen for a 2 valve motor!! The power of that motor must combine torque and horsepower to exceed even the Buell engine!! I would much enjoy seeing that bike on a racetrack!!

 

 

It surely is the narrowest I have ever seen. Men, this is a paradigm shift in Kuhnian terms!

2 valves only, heron-type combustion chambers, pushrod and rockers (but do check the designs of those cammes...) to deliver around 167 hp...

Put it simply: no Guzzi ever - factory or tuned - has ever came close to such performance...

 

:mg:

 

G.

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So I have to ask, why does the Breva 750 make such modest power? Or maybe I should say: wow - the Breva 750 has some real power potential? <_>

 

It's all about the intake tracts: air has mass, making it turn 'round corners (change direction) requires force, force requires energy, energy taken from the moving column of air slows it down, yadayadayada.

 

These guys did their homework; if you take the time to stumble thru the horrible machine translation of the article, [which, btw, w/ todays computer power & AI programming you'd think the translation programs would have search patterns for idiomatic expressions & brand names built in, so that "Moto Guzzi" for instance would be translated as "Moto Guzzi," instead of "Guzzi motion..." all the time] you'll find that they really focused on application of modern combustion theory; Carcano was designing the Guzzi big-block V2 40 years ago, and the factory hasn't really changed the details all that much in the intervening years... and there's only so far you can go w/ 1940's technology! :huh2:

 

Between water-cooling the head [which allows higher compression before pinging sets in] and comprehensive design of the combustion chamber & intake tract [more of the same, + better breathing], and added displacement [no replacement for displacement, as they say!], the Big Bore is a great indicator of which way the factory could go [if Piaggio wanted.]

 

Conversely, the Tonti-designed small block in the Breva 750 is pretty much stretched to its limits; without a comprehensive redesign of the intake tract similar to the Big Block [which will net smaller %age gains vs. the hemi heads on the big block Carcano motors], it just can't breathe well enough [there's some web data to support this out there (Eurospares, for one)] to do it, plus there's not enough strength in the cases [which started life w/ half the Breva's displacement, don't forget!] to handle too much more power.

 

Anyway, that's the story as I heard it... ;)

 

Ride on!

:mg:

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It's all about the intake tracts: air has mass, making it turn 'round corners (change direction) requires force, force requires energy, energy taken from the moving column of air slows it down, yadayadayada.

 

...

 

Thanks Skeeve. Appreciate all the info in your post - explains a lot.

 

For some reason I though the Herron head was inherently (no pun) inefficient. Obviously not the case, otyher things (as you point out) being equal.

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