Ducatis To Get 3kg Weight Reduction

It is the fate of the World Superbike class to be ever surrounded in controversy. At the heart of the problem lies the so-called parity rules, the rules which have been drawn up to ensure that the different engine configurations can compete on a more or less level playing field. Each time these rules have been modified, there has been an outcry, and the latest switch - the expansion of the rules for twins to allow Ducati's 1200cc 1098 to compete in 2008 - was no exception. When the capacity for the four cylinders was raised to 1000cc, the Japanese factories raised an outcry, over the limited tuning they were allowed to do to the engines. But the expanded capacity made it much cheaper to run a four, making the (then 1000cc) Ducatis incredibly expensive to run, as they were full of lightweight components and needed constant revision.

With this experience behind them, when the capacity for twins was expanded to 1200cc, the parity rules were not set in stone, but a set of parameters were set out under which adjustments could be made to the rules, based on a simple and elegant scoring system. Under this rule, if an engine configuration of one type was leading the championship, and the two highest scoring bikes of that configuration had outscored the other configuration by an average of 5 points per race weekend for three races in a row, then first the weight limits, and then air restrictors would be adjusted for the twins, to make the racing more even.

That milestone was passed this weekend, when despite Michel Fabrizio's clear victory in the first race at Kyalami, the leading four cylinders scored an average of 5 points per event better than the leading twins over the past three races, and the Superbike Technical Director has taken the first steps to return to parity, by reducing the minimum weights for the twins from 168kg to 165kg, to be allowed from the next World Superbike round at Miller Motorsports Park on May 31st. The weight reduction is the first of two possible reductions, the next step being to reduce the minimum weight for the twins from 165 to 162kg.

The weight reduction is likely to meet with a mixed reception, for although the Ducati teams have clearly been at a disadvantage this season, none of them have been calling for a reduction in weight. Instead, the cry has been for the 50mm air restrictors to be enlarged, a move which will not be permitted under the rules unless the Ducatis continue to score badly for another 6 races in a row. Only once the restrictor size has been upped from 50mm to 52mm will the Ducati teams be happy, as the problem the bikes have is a lack of horsepower compared to the four cylinders, rather than an excess of weight. Indeed, neither the fours nor the twins are believed to be anywhere near their minimum weights, and efforts to get down to that weight would involve spending exorbitant amounts of money on components made from exotic lightweight materials.

But as elegant and clever as the parity rules are, both the 2009 and 2010 season demonstrate just how great the human factor still can be. In 2009, an American called Ben Spies came into the series, and dominated from the moment he got on the bike. The exceptional nature of his talent was apparent from the state of his teammate Tom Sykes, a BSB front runner, and a rider who has impressed since moving to the Kawasaki. Take away Spies from 2009, and the Ducatis would probably have received at least one weight increase last year, if not two.

And Spies appears to be responsible in part for the reversal of fortunes for Ducati, as his defeat of Xerox Ducati's Noriyuki Haga has left the Japanese rider a mere shadow of his former self. With Haga - formerly a rider who could be counted on to consistently win races, and compete at the top of the championship all season long - completely out of form, the baton has been passed to his teammate Michel Fabrizio, who is fast but notoriously inconsistent, and the privateer Althea Ducatis of Shane Byrne and Carlos Checa, whose bikes have been detuned slightly to ensure reliability and keep down costs.

There's a saying that motorcycle racing is still about 80% rider and 20% bike, and World Superbikes' parity rules seem to underline the truth of that aphorism. For though the rules focus only on the bikes, the exceptional form of Leon Haslam, and the revival of Max Biaggi suggest that it really is about the rider, and not so much about the bike.


"Indeed, neither the fours nor the twins are believed to be anywhere near their minimum weights, and efforts to get down to that weight would involve spending exorbitant amounts of money on components made from exotic lightweight materials."

You are in a better position than I to know the truth, but this statement boggles my mind. My POV is from the world of Le Mans and F1 - the top cars in those series need ballast to meet the minimum weight regulations. In fact, almost all F1 cars are underweight and have several locations "on the floor" where tungsten ballast can be placed, so as to optimize the vehicle CG for the track in question (or the driver's style). Le Mans prototypes are similar, but only the top teams like Audi and Peugeot have gotten their designs to the point where ballast is a luxury they have.

I know that a racing motorcycle is a completely different beast, but are you telling me that these engineering marvels are "[no]where near their minimum weights"? Is the same true for MotoGP? I need to look back at my Neil Spalding MotoGP Technology text.

Total votes: 49

I think what you're overlooking are the differences between cars and bikes. For a start, F1 and (if I understand it correctly) Le Mans are prototype series, with vast freedom to design and build chassis. They are not constrained by being forced to use production engine cases and production frames, which his where the majority of the weight is. Secondly, budgets are incomparable between the two series, with budgets in F1 probably two orders of magnitude larger than in WSBK. Thirdly, because the bike is a relatively minimalist design (once you strip off all the parts needed to make it road legal), there is not all that much more weight that can be dropped. Certainly, carbon fiber wheels may drop 5kgs off the total weight, but forks are forks, and there's not that much to weight to be lost for them, at least not while maintaining performance and stiffness.

This problem cannot be underestimated: Most MotoGP bikes - built with complete freedom and much larger budgets - are also over the minimum weight, and some of the Moto2 bikes are as much as 10kg over the allowed minimum. In all motorcycle racing series, we are well into the area of diminishing returns in bike design, where costs are starting to spiral exponentially.

Total votes: 53

David - thanks for the explanation. I suppose it would be an outstanding engineering leap if someone COULD get bike weight below the minimum. Maybe the FIM can offer a prize (similar to the X-Prize) for the first MotoGP team to do so - any win a race. :-)

"In all motorcycle racing series, we are well into the area of diminishing returns in bike design, where costs are starting to spiral exponentially."

Your very well written analysis and commentary of this (was it two yeasr ago?) returns once again.

Total votes: 38

according to my maths.

Philip Island saw the twins get 20 + 16 pts race1 and 25 + 16 pts race2, event average = 38.5; the fours got 25 + 13 in race 1 and 20 + 13 in race2, event average = 35.5

Portimao saw the twins get 13 + 10 pts race1 and 13 + 9 pts race2, event average = 22.5; the fours got 25 + 20 in race 1 and 25 + 20 in race2, event average = 45

Valencia saw the twins get 11 + 8 pts race1 and 25 + 20 pts race2, event average = 32; the fours got 25 + 20 in race 1 and 16 + 13 in race2, event average = 37

Averaging the event averages: twins on 31, fours on 39.2 - more than 5pts gap and Haslam leading the Championship, hence a weight reduction was due.

Not sure why it didn't happen.

Total votes: 40

i read it as being a single average for each event, so there needs to be 5 points difference at each of the 3 events

at philip island your math shows a 3 point difference at philip island which is why it doesn't count

may be wrong but it's how i saw it

Total votes: 51

1. By taking the race points of the riders of the best two 1000 cc 4 cylinders
and best two 1200 cc 2 cylinders in each race, and calculating an average will be calculated after every event, the ‘event average’.
If there is only one finisher from one of the configurations, the ‘event
average’ will be calculated from the first rider of each configuration in each race.
No ‘event average’ points will be calculated if one of the configurations has no finishers. The ‘event average’ will then be calculated, based on the results of the other race from the same event.
2. ‘Wet’ races (as declared by the Race Director) are not taken in account for the calculation of an ‘event average’.
3. After 3 events, the average value of the ‘event averages’ of each configuration will be calculated.

From the official calculations linked below they work out an event average as being a single race, ie divide my numbers by 2. As my average of averages were for events, ie both races, they also need dividing by two. Hence the gap is only 4.1
It was the phrase "event average" that caught me out *blush*. At least my maths was OK!

Total votes: 45

I have always hated restrictor plates. Even though I have never seen one.

As a result, I have a question that I have been unable to find the answer to.

I have to guess that the 50mm restrictor is total 50mm and not 2x50mm (one for each throttle-body), is that correct?

If so, I am stunned that the Ducati's are even able to finish as well as they have. My Buell has a Rotax 1125 v-twin and 61mm throttle-bodies. I realize that these are huge even for a large v-twin but still that would be nearly three times the size is a single 50mm restrictor.

MotoTheory.com - MotoGP Data & Statistics

Total votes: 47

The air restrictors are per throttle body. So the Ducati has two restrictors, each with a diameter of 50mm. 

Total votes: 43

And this comes after this weekends races when the broadcasters on Eurosport made a note to point out the variety of different makes running up front and also winning this season and how that's a clear indicate to them that the rules were just about spot on.

And maybe this is just my memory but it always seems like it's Ducati that get's the rules bent in their favor. Maybe if their riders this year would just ride as hard as the rest of the guys up front they wouldn't need to increase the size of air restrictor's or drop weight.

Total votes: 50

..despite all the differing points, WSBK has thrown up some fantastic racing so far this year, Flamminis must be doing something right!..tell you what it is..?
They had the courage to stand up and say.."OK if that's the way you feel, there's the door"..something Ezpeleta could bear in mind while sorting out the MSMA.

Total votes: 43

What I am missing in this article is that the weight reduction for twins is not a weight advantage. The limit for them was 168 kg, now it will be 165; fours have a limit of 162 kg, so the 1200cc twins still have a weight penalty. And then there's the 50mm air restrictor, another limitation the fours don't have. People seem to think you have to restrict the twins because they have 1200 cc, but the major restriction is simply the fact they only have two cylinders! That restricts revs and valve area, and therefore they get more capacity. It's a simple engineering fact. It strikes me as very twisted that then they get several restrictions because of their capacity advantage, as if everybody immediately has forgotten they have only half the cylinders. I guess a large part of the public does only understand capacity and not the engineering limitations of twins compared to fours. Still, the rulemakers should be smart enough.

Total votes: 50

It not about number of cylinders, it's about balancing the torque of the twin with the top end power of the fours so that no one type of engine has a big advantage. The only thing wrong is that the factory xerox boys as previously said,.. are underperforming.

Total votes: 50

Sure the twins have more torque because of their 1200 cc's (not because they are twins), but since they cannot rev as high, they need longer gearing to reach the same speeds, and the longer gearing means the force at the rear wheel is reduced. So while the engine torque is higher, the driving force at the rear wheel will be the same as with the fours, as long as they make the same horsepower. So the twins don't really have an advantage from the higher engine torque, it just means they make their power at lower revs. And yes, it will feel very different.

Total votes: 52

That sort of doesn't tell the whole story. A twin of the same displacement as a 4 will not be able to rev as high. Two motors that produce the same torque but rev to different cielings will produce different hp numbers. If a twin can only run to 12k RPM while the 4 revs to 14k and both produce 80 ft/lbs of torque (just numbers pulled out of the air) the twin will only produce 182bhp while the 4 will produce 213bhp.

Regardless of gearing, the twins are at a disadvantage if they are of the same displacement. It isn't just a matter of where they produce that peak torque.

MotoTheory.com - MotoGP Data & Statistics

Total votes: 46

You are absolutely right. Twins cannot make the same power as a four of the same capacity (if they are at the same level of engineering!), because power comes from a combination of torque and revs, so less revs means less horsepower. This is why it is fair that the twins are allowed to have more capacity, like I already mentioned in an earlier comment above. So we totally agree.
In this case here I was only reacting on the remark that the 1200cc twins supposedly have an advantage because of their higher torque. This seems to be a very widespread misunderstanding, helped by the fact that it is mentioned by tv commentators over and over again. Not many people seem to realise the influence of the longer gearing. I even heard respected team managers like Ronald ten Kate complaining when the limit for twins was upped to 1200 cc that it was not fair, "because it is not just about power, they will have more torque than us". Well, it IS about power, because that determines the driving force at the wheel at a given speed.
Actually, I think 200 cc extra for a twin is not really a big margin on an engineering basis.

Total votes: 49

In general: making rules to give more or less equal chances for different cylinder counts is a good thing, especially with roadbike-based racing. That makes for interesting grids. The rules should be primarily based on engineering principles though, not simply on results, and especially not during the season. That way you would punish factories and teams that do their job well, and reward the ones that have not done proper development. I mean, if you do a really good tuning job and make a fast engine, you get smaller restrictors, and if you do nothing and score bad results, you get larger restrictors as reward? That's not really motivating, is it? Of course this thing would hardly play up if there were more manufacturers with twins, but at the moment it's just Ducati, so the performance of their bike will directly influence the rules.
Basically, this sort of ongoing rulechanging means that the organisers wil determine what results you are allowed to score, not your own performance. (Funny, it reminds me a bit of communism.)
Still, this year the rules seem to work out perfectly fine, given the mix of bikes at the front. It's so much better than MotoGP! I would't mind giving the twins the same 162kg weight limit as the fours though, seems fair enough.

Total votes: 48

This is why I am uncomfortable with WSBK rules. NASCAR does the same sort of thing. Yes, racing is close. Yes, results are unpredictable but how do I know who is actually the best rider? How do I know who has the best bike?

It is hard for me to actually care who wins in WSBK.

MotoTheory.com - MotoGP Data & Statistics

Total votes: 40

The Flamminis have previously stated that in MotoGP people follow a rider, in WSBK they follow a brand.
Whether this is true from a fans perspective is largely a moot point, as this is the attitude of the people who make the rules.

Total votes: 46

Motocross bikes in the AMA have used ballast. I remember watching a factory mechanic ('87?) replace the major bolts with titanium and then put on a lead skidplate to bring the weight up to the minimum.

Honda used to put the fuel where the airbox is and the airbox up high. They needed a fuel pump, but they got cleaner airflow with some wind force behind it.

Now they run production bikes & can't experiment as much.

Total votes: 46