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Discussion Starter #1
I'm guessing by now a few have seen the GranTurismo V4 engine driving the new Multistrada. So they have done away with the desmodromic valve system and flipped to springs and collars.

Claudio number 1 dominoe stated it increases the service cycle to 60 000km.
That's an Interesting shift in technology!!
 

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Something that we speculated about regarding 32 valve adjustments for a touring bike.

I wonder if it's still a big bang engine or has a traditional firing interval?
 

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Discussion Starter #5
Something that we speculated about regarding 32 valve adjustments for a touring bike.

I wonder if it's still a big bang engine or has a traditional firing interval?
My guess is that it fires like a V2 with two on the horizontal and two on the vertical cylinders firing together. That suggests to me it's a big bang engine.
 

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Amos, I think the crank pins are offset so that the two side by side cylinders are slightly out of phase but not two 270 crank pins firing together.

Big bang Duc 90 degree V4: 90-200-90-340 (3am, aprx 9:40am, aprx 12:40pm, midnight) (check my math)

Standard 90 degree V4: 180-90-180-270 (6am, 9am, 3pm, midnight)
 

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Yeah, it's an offset pin so it fires left cylinders 90 degrees out of phase with each other, then the right cylinders fire 180 degrees around, 90 degrees out of phase. They call it a "twin pulse" or something, same as on the other Ducati V4's. My rudamentary understanding is that it's the same basic V4 motor with a slightly larger bore and spring heads, with a limited top RPM to manage maintenance intervals.

It also has the ability to deactivate the rear bank of cylinders under cruise to manage rider heat and reduce fuel consumption. Here it fires like a parallel twin with a split flat-plane crank.
 
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