4 stroke GPs

[racer69]

Although there will be a variety of the make up of bikes on the grid next year, do you reckon that as time goes on everyone will start to choose the same engine configeration. In F1 everyone used the V10 engine, and in Superbikes the V Twins are proving dominent, so others are joining.

[gomick]

possibly, time will tell - what is kenny roberts modenas team doing next year and the year after with there 3 cylinder bike......seems they have been around for a while now, wouldnt make sense to quit now would it

[asha]

Racer69 yeah I can see that happening already!
If you look at what suzuki are doing right now, or should I say not doing!! Suzuki have no plans to run a four next year. And have announced that they are not funning a 4 till 2003.
I guess they reckon that sitting on your hands is a good plan, and why spend a **** load of money just to end up copying someone else in the end anyway!

As far as TeamRoberts goes I think they are just going to keep plugging away at it!!!
I don't have time to look at the moment but I'm sure the answer will be at this link!!
http://www.robertsgroup.com

[elephino]

It's an interesting question actually. With 4, 5 and 6 the most likely formations it could go to any of them really. It will be a few years before it happens at least.

[asha]

Should be just as interesting as who will be riding!!

I wouldn't really expect a team to have two different machines but it maybe the case, you would think that team development would dictate it, but I guess its the same as having a v-twin and a v4 (a la Shell)

This just in:
Poncharal plans to give both riders a YZR 500, although an impressive performance by Nakano in private tests at the Catalunya circuit on the 7th and 8th of this month on the M1 has led the Frenchman to admit that Nakano could ride the 4 stroke machine should Yamaha desire so. Nakano set a best lap of 1'45'7 at Catalunya on the M1, just 0.2 seconds off Valentino Rossi's pole time from this year.
(motogp.com)

[Robbieracer]

Hi all. the question of which engine will shake out to be the optimum in GP1 is unlike any other racing we have seen.
Using current Formula one technology, even a V twin can produce about 235 hp at 14800 rpm.
Using the highest tech valve gear in the world (short of pnuematics), for example indycars, a triple would be an almost exact transplant from their 2650 v8, with allowances made for the fuel notwithstanding.
One engine ( made by Ilmor 2 years back) allowed for a 90.8 mm bore, and 14,400 rpm max. Easily enough revs for 230+ hp at 14000 rpm.
Moving to a 4 cyl motor, well just enlarging the 192 hp (at the gearbox) RC 45 would give 229 hp and 13810....
5 and 6 cyl motors would of course allow for more power, or perhaps the same power at lower revs...allowing the use of heavier vtec valve gear for example. In this way, a variable valve V5 Honda might have the mid range of a twin, and the top end beyond anybody els's dreams!
The RC45 analogy would equate to a maximum 247 hp at the gearbox..add 3 years new ideas ..
Add to the mix the possibility of fuel usage being an issue, and the plot thickens.

And if the rear tyre remains the limitation, the engine with the best controllability may win, regardless of the number of pistons.
2 or 3 piston bikes are allowed to be lighter than 4/5's . They may well find there is no need to give them this advantage.

The GP1 organisers may well have produced a set of rules where any number of combinations could win over a year.
:-)
Rob

[asha]

I guess the only question left then Rob is what about the sliencers on the 4 stokes???
Has anyone heard any news on this??

[Robbieracer]

Apparently everybody is complaining about the quiet Yamaha, to the point where the organisers have been trying to talk them into making it louder.
Japanese politics, and the idea of good citizenship may mean that Yamaha remain unmoved.
Honda, however, have built an engine that sounds amazing, and at a press release, played a recording of it VERY LOUD!!!!
Modern silencer tech is good enough now for power losses to be insignificant, so the noise is up to the engineers, or the rules- that peg it to 120db post race, as in BLOODY loud.

[asha]

Mick rode the 4stoke before the 8 hour at suzuka.
But I haven't seen or hear any footage of it? (I didn't see RPM)
I can't beleive its not out there??! There was only a few thousand people there!

I've heard the yamaha M1 (motogp.com webpage).
I thought it sounded like a GP car.

120db!!! common now my stereo gets louder then that!
TURN IT UP!!

[Robbieracer]

Ask, and you shall receive ;-)

http://www.motorcyclenews.com/racing...cumentID=77261

You need real player installed first

Rob

[Gerrit]

The optimum road racer already exists- it is the 500 V-4 two-stroke.
The best 500s give around 200 hp, which is what current chassis, suspension and tyre technology limit bikes to. Building something that develops 240 or more hp is pointless; tyres won't last- it is as simple as that.
And if tyre, chassis and suspension won't limit power, then fuel will. Kevin Cameron was quoted a consumption of 5.6 km/litre for the Honda RC51. Taking Assen as an example, 120 km race distance plus sighting and warmup laps give a minimum consumption of 5.5 km/ litre based on the 24 litres the four-strokes will be allowed next year. Using this figure, the RC51 finishes- barely. But with the 22 litres as of 2004, the consumption has to improve to 6 km/litre- the RC51 doesn't finish. And the RC51 does not develop the power required to run with the NSRs, YZRs and RGVs. Given equal engine efficiency, more power means more fuel required. Race with the two-strokes, you don't finish, and don't win. Slow down to finish, you don't win either. Catch-22.

[Robbieracer]

Hi, it is well known that thr RC51 in road and race guise sucks fuel.
Remember that it is a road engine, with technology perhaps 15 years behind formula one..and formula one rules are more restrictive than the GP1 rules...........
Formula one engines obtain insane power not just through revs, but by being very efficient.
This efficiency will save a huge amount of fuel.
Two strokes obtain their power by firing twice as often.
Their porting is better, and they have nice combustion chambers.
They are also very dirty, SUCK fuel, and can be vicious things to ride.
The new engines will almost certainly be more ridable, so we should see less difference between riders.
Tyre and maybe fuel usage will be the key: so their will need to be a skill shift by the teams and riders.
It will become less of a battle, and more of a science..just like 500cc has become over the last few years.

Beacuse a 2 3 4 or 5 cyl can all make enough power, there will prolly be many engine configurations for marketing reasons as much as anything else.
This is probably a good thing!
Rob

[Gerrit]

Yes, the RC51 is a road engine.... but a homologation special using a lot of race technology to make it WSB legal.
Specific fuel consumption of F1 engines is not all that hot- but F1 cars are aerodynamically far more sophisticated than even the very best bikes and a lot of F1 performance comes from this fact. So the RC51 figures are a fair indication of what the new Wonder Weapons will actually do.
As for restrictive F1 rules, the only real difference is that F1 has outlawed oval pistons- a Honda monopoly.
The fact is that current engines are already very efficient. If the RC51 produces about 165 hp for 5.6 km/litre, 200 hp will require 20% more fuel. This increases consumption to 4.6 km/litre.
As for two-strokes, assuming they use all of the 32 litres for the same 132 km, this gives a minimum requirement of 4.1 km/ litre to just reach the finish line. BUT- they not only reach the finish line, they also complete the slowdown lap and enter the pits without spluttering to a halt, so they actually get at least 4.3 km/litre. Not that much different from the four-strokes- so much for "fuel-guzzling two-strokes".
And if necessary, they can always switch to injection. The NSR500 injection which Shinichi Itoh rode in 1993 gave, according to HRC figures, a saving of 5%. And the injected Aprilia 500 which Jeremy McWilliams rode last year gave a saving of some 10%.

[Robbieracer]

When I was referring to efficiency, I was talking about the aniout of friction in the engine, anf it's specific fuel consumption.
For F1 engines to achiev 850+ hp from 10 cyl 3000cc at only 17500rpm, they are massively more efficient than any road or normal race engine.
This comes partly from coatings and materials technology, and partly from the tightest tolerances ever used.
A company like Ferrari or Ilmor (Mercedes) produce race engins + - one quarter of a percent. Give ot take 2 hp out of 855.
That is accuracy!
it is a fact the at fuel used per horsepower on the current 2 strokes is much higher....especially at part throttle.
There is nothing stopping designers using direct fuel injection, AUdi saved 8% at full thrittle, 15% at aprt, at Le mMans, and that was over an already ideal system.
As I understand it, direct fuel injection is not legal for the 2 strokes.
Formula one is not a good guide for fuel usage, as their wings increase cornering speed, but also fuel efficiency.
Take the wings off an F1 car, and the fuel saving would be massive..

Anyway it matters not if a 2 stroke is more efficient: the rules have been written to make them obsolete.

p.s. never compare an rc51 with a formaula one engine: or what is available under the new GP1 rules.
175 odd hp per liter versus about 235 if built to the current F1 rules: no comparison,.
Further thoughts: many things are legal in GP1 that are not in F1: pistons that are not round, beryllium, metals and composites above a certain stiffness, no limits on water pressure and temperature, no limits on having round poppet valves, far more pistons per liter are allowed.
SO if Honda, BMW or anybody else wants to go wild, they can break the "gentleman's agreement re materials and produce an incredible efficient motor.
We will be heading towards maybe 215 hp at only 1100 rpm

Rob

[Gerrit]

I don't know where you got the information from that DI is illegal for two-strokes, but I have not found anything in the rulebook that prohibits it. Indeed, if the idea is to develop new technology, banning DI would prevent precisely that.
Beryllium pistons, oval pistons, coatings etc etc? Very nice, but who can afford that? And who have direct experience with these? Only Honda- who are the ones behind these crazy rules in the first place. The money simply isn't there in motorcycle GP. As Kevin Cameron remarked recently, "If there really is so much money available for motorcycle racing, surely we would have seen it already?"
Repsol pay HRC $ 4 million this year to sponsor three riders on NSRs- Rossi, Ukawa and Criville. But for next year, they want no less than 12 million. So... what do Repsol get? Guess what- three NSRs and ONE RC211V- in other words, for the privilege of sponsoring ONE bike more, they have to cough up another 8 million. This 8 million would get you SIX NSRs. Guess which is the better deal for a sponsor. And not only that, Repsol will no longer have a say in who rides the bikes. Will Repsol suddenly treble sales of their bike products, to justify such an extra outlay? Hardly likely, is it. Sponsors are business people first and foremost- and six NSRs is a better deal than one RC211V.

[Robbieracer]

Hi, beryllium is not hugely expensive. Pistons can be bought off the shelf. It might be the cheapest way of making a light bike, rather than titanium gearboxes or tricky steel, magnesium with a short working life.
Why is it so? Because it is tough! The pistons last much longer.
So do bores.
This information is freely available in the specialist press.
It's banning in F1 had to do with politics, plus the cars would suddenly be maybe 40 kg further under their weight limit, in a time where some teams carry as much as 65 KG ballast already.
I think it is very important to view the regs and technology against what has already been done in Indycars, Formula one, and rev limited classes like touring cars.
Who said racing was meant to be about progress or developement?
It is about commerce, and the Manufacturers, rightly or wrongly, have brought these rules to bear.
Another thing to consider is that 2 strokes have a limited market, and no appeal to those new to road motorcycling.
4 strokes brings plenty of marketing relevence, and some technical relevence to the top formula.
repsol may be getting the biggest bargain: the cost relative to the publicity might be the best deal Grand Prix motorcycling has seen for years!
On the subject of ultimate, it is interesting to see just how little the current GP bikes get for there 250cc above the 250s or superbikes.
If tyres are the limit- and this is likely to be even more so in the future, surely we will end up with a whole lot of technical grandstanding, and the championship decided by the tyre usage.
We may well have the world GP! back tyre championships.
Bizzarre

[Gerrit]

Beryllium, in case you did not know, is toxic- not the metal to use if one wants to promote environmentally friendly bikes. And have you calculated how much weight a set of beryllium pistons would actually save? Very little. Furthermore, it is more expensive than the most expensive aluminium piston alloys.
Two-strokes can be cleaned up, thanks to new DI technology. And while they may not have much relevance to Highway Donkeys like Gold Wings etc, they do have relevance for sportbikes. They offer manufacturers sharply reduced manufacturing costs, costing about 70% of a comparable four-stroke. They can be much lighter than four-strokes, with the trend going to lighter and lighter sportbikes this is an easy weight saving which does not require the use of magnesium engine castings as used on the ZX-9R and others. DI won't cost the earth, and with more and more bikes being fitted with injection systems anyway, cost can hardly be an excuse.
Two-strokes a limited market? No appeal to those new to motorcycling? Has any market research been done on this? I doubt it. Manufacturers to a large extent abandoned them for environmental reasons in the 1970s, yet they happily continued to race two-strokes ever since. So that reason for switching is hogwash, if it was so important they would have done so years ago.
Repsol have been getting enormous publicity for years, and the RC211V won't get them more.
As for how little 500s get for 250cc over the 250s, will the new bikes get so much more? And can anybody answer me why four-strokes "deserve" double the engine size of 500s? If four-strokes are oh so superior, let them prove it the hard way- on equal terms, not by cheater rules. In reality, those rules just prove what a hopeless engine the four-stroke really is, if they can only get competitive with two-strokes with double the engine size.

[Robbieracer]

Four strokes pollute vastly less. They use far less fuel per horsepower. They are what most maufacturers want to promote, so the superriority or otherwise of an engine system is really just an idealised notion.
We could measure engines many ways: power per litre, fuel used per horsepower, pollution per horsepower, commercial relevence, engine note, weight per horsepower...
And by the way beryllium is only pisonous in dust particles of a certain size. Nothing to do with anything outside of a good clean machining operation in the production room.
Berryliium could be used for almost any aluminium part on a bike....
Frames, wheels, blocks, heads, pistons...you name it..
The new 4 strokes have created vastly more press than the 500/fours, especially in the non-specialist press.

[ChrisUSA]

you bring up some good ideas. let me bring another - 2 strokes use up less space - a far more precious commodity these days than fuel. let's face it, a 500cc 2stroke takes up the same space as a 200cc 4stroke, and makes the same power as a 900cc 4stroke. yes it is less efficient with fuel. but i have never heard - ever - of a race or racing event based on fuel mileage, or emissions for that matter. also, i believe noise pollution to be far worse than any air pollution - how come high performance 4strokes(both roadracing and motocross) are given the ok to be obnoxiously loud?

[JGM]

An obnoxiously loud two-stroke is simply a pain in the ears. An (to some ears) obnoxiously loud, multi-cylinder four-stroke can be compared to, well, a symphony of the mechanical arts. How many of you have heard the 250cc or 297cc Honda six bikes as ridden by Mike Hailwood. If we ever get even remotely close to this again I'll be well pleased.

[f2001]

i cant see maufactures like honda and aprlia breaking tradition...

[moto1]

Suzuki are running the four stroke as you all Know. Honda will be the kings of the four stroke class, and the road! new V5 fireblade anyone? after all the true reason they changed to four stroke is SALES. And what about the MuZ project? I'd like to see a return of the V8, isn't that bloke from AUS building one? aaarrrrrhhh yes the drysdale, isn't it?