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  • 2011 Valencia MotoGP Saturday Round Up: On The Happy Demise Of The 800s, And The 2012 Silly Season   2 years 42 weeks ago

    The tires, the closed motors, the limited gas.

    These things make predictable, processional racing. All these things are staying next year.

  • 2011 Valencia MotoGP Saturday Round Up: On The Happy Demise Of The 800s, And The 2012 Silly Season   2 years 42 weeks ago

    The reason the racing is said to be boring is because Stoner is capable of putting 1s/lap into Pedrosa on a bike with the same potential.

    That suggests that the rider has too much influence, not too little... if close racing is what you value most.

  • 2011 Valencia MotoGP Saturday Round Up: On The Happy Demise Of The 800s, And The 2012 Silly Season   2 years 42 weeks ago

    1. Linear momentum of the pistons etc sums over all the cylinders and so is largely ignorable.
    2. Even in a big-bang engine where it doesn't cancel, the time average is exactly zero. Hence if at one instant the pistons are resisting the change of axis, a few ms later they are helping.
    3. I think you need to look up angular momentum, which is what produces the resistance to change of angle you are thinking of. It is dominated by the rotation of the crankshaft and is proportional to the product of the moment of inertia and rpm. Hence a heavier crank need not have greater angular momentum if it is in a lower revving engine.
    4. Piston sizes will not increase in the Ducati. We do not know bore vs stroke figures for the other bikes, but assuming they are close to the 81mm limit, the same may apply. So no need for heavier pistons (or heavier counterweights on the crank).
    5. If the bore remains the same, the stroke must increase by 25%. However if mean piston speed is to remain the same (it's a good indicator of longevity) then peak rpm must decrease by 25%. See comment above about calculation of angular momentum.
    6. In fact they'll probably get away with slightly higher piston speed because peak piston acceleration increases with rpm squared, so they'll probably have slightly higher AM... but I reckon the improved auto-blip and other slipper clutch type mods had a bigger contribution to increased corner speeds.

  • 2011 Valencia MotoGP Saturday Round Up: On The Happy Demise Of The 800s, And The 2012 Silly Season   2 years 42 weeks ago

    If Cinderella's castle and Neuschwanstein are the same building, you're posting on the wrong website. However, I suggest you stay and learn the difference between Teutonic masonry and a parking garage with a tilt-wall facade.

    Both can be enjoyed in their own way when they are understood. But if you take family pictures at Cinderella's castle in your lederhosen, you look like an asshole. Just giving you fair warning.

  • 2011 Valencia MotoGP Saturday Round Up: On The Happy Demise Of The 800s, And The 2012 Silly Season   2 years 42 weeks ago

    They are stroking the engines to get them to 1000cc, and some reports indicate that Ducati reduced their bore dimension to meet the 81mm limit. If engine parts are getting heavier in the 1000cc era, it will likely be the rods which may get longer to preserve stoke-rod ratios.

    If engine internals remain unchanged, but the stroke is increased from 38.8mm to 48.5mm, the engine should produce about 18% less acceleration at peak rpm. They have piston acceleration calculators you can use for free on the net. If that were the only variable in this equation, the 1000s would generate less gyroscopic forces. However, the amount of gyroscopic force is determined by far more variables than we have access to, and we don't know how reciprocating engine parts will change as a result of 25% more stroke.

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    The difference in acceleration was not evident until both riders were well out of the corner, straight up and down and already well beyond the rumble strips. This was not simply a different line or good drive scenario!

    The partially wet race and tricky conditions led to longer lap times and therefore more fuel available at the end. I know that there are on the fly mapping switches on the bikes, maybe Casey hit the full power turbo win it or bin it setting, whilst Ben was busy trying to make it to the line? Who knows.

    This speaks to something that I've suspected for a while now - that the Yamaha makes decent power, but Honda is way ahead in fuel management. Therefore Honda can make more use of the available fuel whilst Yamaha has to dial down power to maintain fuel consumption and finish races.

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    I am more interested in what both the riders had to say, and that's what I quoted. Spies and Stoner had more than one interview, and you should read them to get a full rider perspective. I said in a previous post that traction has been a Honda strong point for the last season and a half, but the last corner was not just about Honda traction. It was about how Stoner used the traction when he found a gripier piece of track. It was also about mental strength: a guy who has just wrapped up an almost flawless championship and decided to take a risk to win the final race versus a guy who has recently had several crashes and injuries and was happy to settle for second rather than risk crashing again. Things are not always what they seem on TV.

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    I knew Spies was in trouble as soon as he came out of the last corner. His exit was really wide and put him on the paint and curb, partially in the pit entry even...he just couldn't get on the gas when he wanted to.

    Great race nonetheless, good riddance to the 800s.

  • 2011 Valencia MotoGP Saturday Round Up: On The Happy Demise Of The 800s, And The 2012 Silly Season   2 years 42 weeks ago

    There's not much Dorna hasn't fiddled with during the 800 experiment, but so far the laws of physics have managed to stay out of their reach.

    Larger pistons are heavier pistons. Heavier pistons increase the gyroscopic effect of the motor in the context of its relationship with the other forces acting on the bike. These forces are at play within the engine at all rpm, and have a direct effect on the way that the bike behaves.

    The bike still weighs 145kg, same as the 800, but now instead of 4kg of ballast to bring it up to minimum weight let's say there is now 3.98kg of ballast, as there is an extra 50g per piston to take the bike to 1000cc (wild guess, the actual increase in piston weight is not important in this). How can that affect how the bike rides? The thing to consider is that the 200g we are talking about is now dynamic, rather than static. And not only is it moving, it is moving at insane speeds. That mass is multiplied by velocity to give momentum and because larger pistons mean more momentum, the amount of secondary force required to change the relative direction of that momentum must also be increased. I will attempt to explain it here, but please note that I'm no scientist - I did far better in English and Music than in Maths and Physics at school - and corrections to my analysis are welcome.

    There are two factors in play here. The first relates to piston movement in the bore. Force = mass x acceleration. Increase the mass of the piston and either Force or Acceleration will be affected. Since we know that a piston going from BDC to TDC will accelerate up at the same speed for any given rpm regardless of piston mass (all other things being equal), the force involved (the vector quantity) will therefore be higher for a larger piston.

    A force has magnitude and direction. We will presume that the force acting on the larger piston in the 1000cc engine is acting vertically (well it is probably angled forward for an I4 and either forward or rearward for a V4, but easier in the example to say vertically). Meaning it is acting in the same plane as our initial lean angle in the left hander.

    But now that we are transitioning to the right hander, the force on the piston is no longer acting in just one direction, because our second factor - lateral force - has come into play. The piston is still going up in the bore (we'll get to down later), so it's moving vertically in the plane of the bike, but it is now also going sideways. So now that we have more than one force at work, the only way to quantify the forces involved is to use the parallelogram rule of vector addition - meaning that the two vectors in question are represented by two sides of a parallelogram. The sum total of the two vectors is now represented by the transversal of the parallelogram, which is the actual vector for the combined forces:

    http://en.wikipedia.org/wiki/File:Vector_addition.svg

    So if you increase 'a' (being the weight of the piston), then 'b', which represents the physical forces required to change the direction of the piston (from the angle of full left lean to the angle of full right lean) MUST be increased to keep the same resultant vector 'a+b'. If you don't maintain the vector quantity 'a+b' then you have simply gone slower through the corner because reducing it means you have reduced the secondary force acting against the piston. And remember that we have four pistons, and if we assume a steady 10,000rpm and three seconds from full left lean to full right lean, each piston will have gone from top to bottom and back to top of the bore again five hundred times while the bike is changing direction. Say the stroke is 45mm - that's a distance of 45 metres traveled (22.5 in each direction) in three seconds, and our extra 50g has come to rest then got going again 1000 times! In three seconds! Over all four pistons our 1000cc engine has an extra 200g travelling 180 metres in the three seconds it took to change direction. 4000 stationary moments too, and it had to be accelerated again after every one of them.

    Across four pistons, that's two thousand 'a' vectors using the physics explained above - or four thousand when we count the down strokes as well, which are of course measured as force vector quantities too, along with the secondary forces acting against them.

    The riders, tracks and tyres will be the same as for the 800s, result will be that the 1000s will be slower to change direction and they will not brake quite as well as the 800s for exactly the same reasons. They should accelerate just the same or faster though, also due to the laws of physics - the extra power means extra force, and force equals mass x acceleration so if we have extra mass plus extra force we should see the same acceleration values as the 800s have.

    The riding style required will involve braking earlier than on an 800, then getting on the power hard to use the torque to get out of the corner with a combination of bar input and steering on the throttle. Just like in the 990 days. The upshot of all this is that we should see more passing under brakes than during the 800 era, and we have Newton and his laws to thank for that, not bloody Dorna : )

  • 2011 Valencia MotoGP Saturday Round Up: On The Happy Demise Of The 800s, And The 2012 Silly Season   2 years 42 weeks ago

    All that left is who can jackrabbit start to the front,mand what's the power to weight on the bikes.

    That's why Pedrosa is champion then?

    Oops, the best P/W guy finished ... 4th. Last of the Repsols in fact.

    Oh, it was raining at Laguna Seca when Lorenzo led for 2/3 of the race (and finished 2nd)?

    And at Motegi... ? Where the straight allows the highest top speeds of any circuit, obviously a Honda circuit. Yep, must have bucketed down for Lorenzo to win...

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    Spies said in one of the interviews that he had it pinned out of the corner and that he just got "motored" to the line.

    I tend to believe him, since he was there.

    If you can't see in the videos that the Hondas were pulling Spies out of the corners all race (and all year) then I don't think my point of view will convince you. Oh well.

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    per Lorenzo's color commentary, Bautista braked late. and indeed looking at it again that speed difference did seem noticeable. Still, just a racing incident

    farewell to jLo's distal-phalanges also.

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    Paragraph three, indeed, it doesn't get any better.

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    Stoner has confirmed in an interview that he found a line out of the last corner that was giving him a lot more grip than Spies, and he also used first gear. It was a premeditated move. Spies also confirmed in another interview that he was a bit tentative through the last corner because of the crashes he has had in recent weeks. Spies admitted that he had decided that he would be happy with either first or second. He just didn't want to crash. So Spies was being careful, but Stoner decided it was the last lap of the year so he took a risk and went for it. Stoner wanted the win more than Spies. That's why he beat Spies to the line. Let's give credit where credit is due, and not pretend that it was just Honda power that got Stoner over the line.

  • 2011 Valencia MotoGP Saturday Round Up: On The Happy Demise Of The 800s, And The 2012 Silly Season   2 years 42 weeks ago

    Actually I'm pretty sure the reason Stoner uses little TC has nothing to do with it "reducing the skill required" but everything to do with him turning faster laps times with it at a minimum. If people think that suddenly all this electronic tech should be banned from MotoGP for the reasoning of closer racing well here's some advice-go watch some local club racing. Watch some lower level racing like BSB or AMA DSBK. If all you care about is close racing then go do that. If you want to see the best riders on the most advanced machinery with two wheels then tune in next year to MotoGP!

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    Something went wrong with Spies exit, and it looks like it started mid-corner as he went for the apex. From the overhead, Stoner was much tighter onto the apex, over the paint earlier, than Spies was. This let Stoner exit the corner on a tighter line, and you can see he's on the gas much cleaner, in a tighter line. Spies bike seemed to just get a little upset just as he got on the gas, somehow forcing him out a bit, and costing him his drive. Whether that was related to his slightly slacker apex, I don't know.

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    All race (year) long the Hondas were accelerating out of the corners faster than the Yamaha, not just the last corner of the last lap.

    Casey is a fantastic rider and sure, he got a good drive out of that corner, but that was most assuredly not why he beat Spies to the line.

    I can't wait for next year.

  • 2011 Valencia MotoGP Saturday Round Up: On The Happy Demise Of The 800s, And The 2012 Silly Season   2 years 42 weeks ago

    "phoenix1 on Sun, 2011-11-06 22:25. Dispassion is a qualitative human perception......"

    [......and so on, till eyes bleed]

    Sounds like you haven't enjoyed anything in the last 5 years of Racing, with all the shortcomings you list.

    Some people like to over-analyse things until all the joy is sucked out of them. Your mini-essay did that for me. Try presenting your argument to your average punter at a racetrack, and witness the glassy look in their eyes as you drone on about why Modern Motorcycle Racing is not giving you the perfect spectacle that you so richly deserve.

    I'm sorry that the last 5 years of Motorcycle racing has so frustrated your sensibilities - but it seems like you have missed the point of Racing. Just enjoy it, and try not to sweat the details. You'll give yourself an ulcer.

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    I can't find the words to describe how good this is. Sir, you deserve an award.

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    Stoner got the last corner perfect, Spies didn't. Stoner made up four tenths on Spies on the last lap, and it looks like it was all through the last corner and leading up to the finish line. Stoner is clearly faster through the corner than Spies, and is closing on him. He then sits the bike up earlier than Spies, and on a different part of the track, about a meter inside the edge of the track. Spies runs out over the rumble strip. In these greasy conditions on slick tires certain parts of the track will give a lot more grip than others.

    Fuel should not be a problem in wet conditions when they can't use full power. Spies didn't mention having any problem. In my opinion, it was mostly brilliant riding by Stoner, plus of course the great traction of the Honda out of corners, which has been the Honda's strength for the past season and a half.

  • 2011 Valencia MotoGP Race Result: Weather Throws A Curve Ball, Race Settled At Line   2 years 42 weeks ago

    Perhaps if Dovi could perform like that a little more often then he would have been more valued at Honda

  • 2011 Valencia MotoGP Race Result: Weather Throws A Curve Ball, Race Settled At Line   2 years 42 weeks ago

    Sorry, I meant "lost his seat... in MotoGP". Edwards gets to stay in MotoGP though, presuming the bike materialises. Edwards has had 8 years, and is near retirement age anyway (he's only a year or so younger than Loris). Aoyama has had only 1 proper season in MotoGP - in which he's done quite well really.

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    Is it possible that Spies' bike was running short on fuel? Given all the bikes have enough power to loop over backward in the first 4 gears, the difference in acceleration seemed unreasonable...

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    All the riders were moving right to prepare for turn 1. Bautista braked too late and had, contrary to all those around him, sharply move left in order to avoid crashing into Rossi. Instead he ran into Dovi and skittled Rossi et al anyway. Just look at the speed difference Bautista had relative to other riders, was it really all the others who were wrong?

  • 2011 Valencia MotoGP Sunday Round Up - The Very Many Goodbyes Of 2011, And Hello To 2012   2 years 42 weeks ago

    would be more accurate to my mind. A ten second lead with five to go until conditions became even more dicey.

    That on the line past was the difference between a perfect hook up and a not so good one. Not the difference between RCV and M1.

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