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Rossi vs. Ducati...and more spoilers

Started by gm2, April 11, 2012, 06:33:00 PM

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gm2

ok, now it deserves it's own thread:

http://www.autosport.com/news/report.php/id/98702 
Like this is the racing, no?


zooom

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El-Twin

Rossi's quote reads:

"Unfortunately, I lost a lot of time in the beginning because when I had new tyres with good grip, the rear pushed a lot, making it very difficult under braking."

Can someone explain this to me? I don't understand how the rear end can push. Loose? Yes. But push from the rear, I don't get.

I thought the problem with all of the Ducati GP machines is that the L-twin motor doesn't allow enough weight on the front end to load the tire enough to give feedback. Then, when they rotated the motor backwards to compensate, it also raises the center of gravity. Make sense?
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zarn02

If the GP12 understeers, then perhaps the riders compensate by sliding the rear out and flat-tracking it around the corner. A fresh, super-grippy rear tire might not allow for that, meaning lost time.

Or at least that's how I worked it out in my head that it could make sense.
"If it weren't for our gallows humor, we'd have nothing to hang our hopes on."

El-Twin

^^^ That makes sense to me, thanks.
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If I ever find myself on a winding road, holding up a line of cars with a motorcycle, I will carry the shame to my grave.   -PETER EGAN

MadDuck

However you slice it Rossi is giving them a huge list.

1.  From all riders --- the lack of front end feel. Too stiff??  Not enough front weight bias??

2.  It understeers. Won't tighten up in a corner once you got it turned. (Gee, where have we heard that before, and not just in MotoGP land?   [laugh] )

3.  The rear tire pushes.

4.  The engine needs a softer power delivery.  Rossi had that problem with some of his earlier Yamahas too.

So what then?  Other manufacturers have used and currently use a V configuration engine. So is that it?  They've tried different frames and still have the same problem? How can that be? Is it a rear suspension geometry problem coupled with the engine? Somewhere in all of that there must be some sort of constant that someone either doesn't want to change or that in all the variations somehow keeps coming back.
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thought

The only thing they havent played with is the 90 degree angle of the v4 right?  Could it possibly something weird coming off the rotational forces in that engine config?  Seems like a long shot though...

And i'm wondering, if ducati went back to the trellis frame, something they have a lot of xp with, would that help to solve the front end issues?
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zarn02

Quote from: thought on April 12, 2012, 10:00:16 AM
The only thing they havent played with is the 90 degree angle of the v4 right?  Could it possibly something weird coming off the rotational forces in that engine config?  Seems like a long shot though...

I don't remember hearing all these complaints when they had it sat in the trellis frame, so I wouldn't think the cylinder angle itself is the issue. Maybe weight distribution, which would be a side-effect.

Quote from: thought on April 12, 2012, 10:00:16 AM
And i'm wondering, if ducati went back to the trellis frame, something they have a lot of xp with, would that help to solve the front end issues?

Maybe, maybe not? The trellis-framed GP bikes also existed in the 990 era, with tire choice, etc.

As I recall, they abandoned the trellis because they couldn't get the airbox volume they wanted while using it. How big a problem this actually would be, I don't know. You don't hear anybody saying the Ducati is underpowered.
"If it weren't for our gallows humor, we'd have nothing to hang our hopes on."

JoeP

They've tried everything with the bike. They need to start modifying Rossi. Reflash his PR unit and back out his b!tch screw a half turn or so.

BMiller

Quote from: JoeP on April 12, 2012, 10:22:37 AM
They've tried everything with the bike. They need to start modifying Rossi. Reflash his PR unit and back out his b!tch screw a half turn or so.

[laugh]
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gm2

Quote from: BMiller on April 12, 2012, 10:53:29 AM
[laugh]

+1  [laugh]


and yeah, the only thing they haven't done is mess with the actual shape of the engine.  when they went to work over the winter there was zero latitude on sticking with the 90°.
Like this is the racing, no?

Raux

Personnally would love for them to bring back the trellis

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Triple J

The 90* configuration causes problems because it makes the motor longer, which limits how things can be oriented in the frame to affect weight distribution (i.e. put it as far forward as a 60* V motor and the front wheel hits the cylinder head). A smaller angle between the cylinders leads to a more compact engine and more options.