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Unbelievable how there is still speculation about the chassis. The twins spar al. frame was tried and flopped ........ get over it, its not the frame.
I have given the cure, but I'd even be happy to see them cant the engine back so that the cylinders are 45/45 from the horizontal. . They can work on the narrower V later.
Forget the chassis, its not the major problem. Its having piston motion too close to a perpendicular of the force trying to hold the bike on the track, and causes a difficulty in changing the direction, ie, the bike going round a corner, hence exceeds what the grip can cope with, and it pulses andchanges with engine revs ( don't crack the throttle!! ) Unless you can let the arse end hang out ...... then the front regains a bit of grip emphasis in the whole front v's back grip balance. But you have to steer with the back .... not a Rossi thing to do ...... so fix tat engine!!
The chassis can be playdough or glass or cereal box toy plastic then ......
Forget the chassis..... its been done to death ...... its an absolute waste of time until Ducati fix the main problem ....... almost horizontally acting cylinders, or angles getting close to that!.
I have given the cure, but I'd even be happy to see them cant the engine back so that the cylinders are 45/45 from the horizontal. . They can work on the narrower V later.
Forget the chassis, its not the major problem. Its having piston motion too close to a perpendicular of the force trying to hold the bike on the track, and causes a difficulty in changing the direction, ie, the bike going round a corner, hence exceeds what the grip can cope with, and it pulses andchanges with engine revs ( don't crack the throttle!! ) Unless you can let the arse end hang out ...... then the front regains a bit of grip emphasis in the whole front v's back grip balance. But you have to steer with the back .... not a Rossi thing to do ...... so fix tat engine!!
The chassis can be playdough or glass or cereal box toy plastic then ......
Forget the chassis..... its been done to death ...... its an absolute waste of time until Ducati fix the main problem ....... almost horizontally acting cylinders, or angles getting close to that!.
Do you think Ducati will surely modify the engine angles? I'm pretty convinced too that the frame is not the problem, but the engine and its configuration relative to centripetal forces are impeding the bike to lean easier.
Sorry, sarcasm removed.
Have turned over a new leaf, but sometimes have slight relapses.......
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Nobody has complained about the ability to lean the bike over easily ...... so that's not a problem.
The occasional Ducati rider has complained about the front just letting go when they do lean it over though.
Matter of fact you do raise an interesting point about the "ease of lean" ..... this again would have been in Stoners favour, as in the technique he used to get it round a corner, once initiated, the slide is maintained by body position, throttle and or rapid changes in lean angle and a matrix of combinations thereof according to what was happening at that millisecond.
Fast adjustments of lean angle would be very advantageous. With rapid changes of lean angle people forget that the bike does not only pivot around the tyre contact patches but it also pivots around the bikes longitudinal centre of gravity. In short pulling the bike rapidly inward, whilst in a lean gives a force at the tyre that attempts to lose grip. Inward ( leaning it more ) to get the back out and outward ( picking the bike up ) to gain grip. ( think of a steel bar in space and its struck/enacted at the top by a lateral force ..... what happens to the bottom of the bar? It kicks the other way with the bar spinning around the mass centroid ) Hang your body well off the bike inwards and you have a lot of available grip adjustment in your arms merely by pulling the bike in or out. Keep you weight well up front and its the back that should react to those adjustments more than the front.
Again a useful concept used in Aussie dirt track racing to maintain a slide, especially as modern tall mx bikes began to be used as opposed to the old low slung "sliders", still works for both bikes though. Must have been mindbogglingly annoying for Stoner when he could not rely on the front to react to merely adding more weight to bias the grip balance and ensure the front stayed planted..
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Ummm ...... nothing really to discuss there, apart from one posts worth ........ have you anything valuable to add?
Did you even need to tell the world this? ...... just NEEDed to be involved somehow did you?
Barry, interesting and good post.
Would rotating the engine in the chassis negate the piston movement-perpendicular of the force keeping the bike rubber side down and is that not the main reason they've gone for a twin spar chassis-so they can change the position of the engine....or have they got it all completely wrong...again? I'm no mechy engineer, as you can probably guess!
Would rotating the engine in the chassis negate the piston movement-perpendicular of the force keeping the bike rubber side down and is that not the main reason they've gone for a twin spar chassis-so they can change the position of the engine....or have they got it all completely wrong...again? I'm no mechy engineer, as you can probably guess!
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I think the twin spar is just a knee jerk reaction to all the other chassis failures to date.
But then again Preziosi did say they are planning to build a huge amount of "adjustablity" into it so I guess there are some benefits. ie. Perhaps they can now try engine positions and attitudes with the one frame rather than the hassle of always getting another set monocoque piece made for each thing they wanted to try.
But apart from Ducati it sounds like nobody really has much of an inkling of what they have done at present. Its all pretty hush hush.
But then again Preziosi did say they are planning to build a huge amount of "adjustablity" into it so I guess there are some benefits. ie. Perhaps they can now try engine positions and attitudes with the one frame rather than the hassle of always getting another set monocoque piece made for each thing they wanted to try.
But apart from Ducati it sounds like nobody really has much of an inkling of what they have done at present. Its all pretty hush hush.
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Damn!! twin posts!! let alone twin spars!
Yeah, i think after 2011 they're shitting themselves and its very possibly a knee jerk reaction... Still, they have to try, process of elimination and all that. Theyre gonna feel so sick if it is indeed the engine thats the cause of all these problems though!
Today nothing new, only Checa tweeting this:
"[font=Arial,]1st test this year recovering good feelings on bike (Is he speaking of himself or the bike?), we are working well. I can't say so much, tomorrow more work. Ciaoo!"[/font]
Krop, du have any new info?
thanks.
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I wish they would just out and say what they have done to the bike. If it works, I want to take the cred. for fixing it!!
But then again if they did do what I said, and it was down to "some guy off the internet" ....... how bad would that look
Still wish they'd "fess up"
, just for the ole "techo-nerd" interest's sake.
But then again if they did do what I said, and it was down to "some guy off the internet" ....... how bad would that look
Still wish they'd "fess up"
Good idea to get checa to test even apart from nicky and valentino not being allowed to during the winter testing ban, he has experience of a traditional ducati trellis frame bike which works, albeit in a different formula with a V2 engine.
Trellis frame with V2 engine? All their trellis bikes uses testastretta engines wich is an L-Twin, isn't it?
It is called an L because it is a 90 degree V as opposed to the narrower "V" angles of others, and the motogp engine is basically two of them put together, as I understand it.
Curious.
But a V is a V because of narrower angle, otherwise would be an L (or a wide V lol). I think a V of 90° does not truly exists. The V letter cannot be described with right angle, then a 90° engine is not a V engine.
But I understand, many call the L-Twin just a V2, but dunno if it's a correct statement.
