500cc

<div class='quotetop'>QUOTE(J4rn0 @ Nov 20 2007, 10:44 AM) [snapback]101554[/snapback]<div class='quotemain'>
Interesting can you expand on this a little bit?


Well the 5 and 4 cylinder weight limit happened to be the same for the 990's. Real convinient for Honda because apparently all they needed to do was add a cylinder to the RC45 engine and they were laughing.

<div class='quotetop'>QUOTE(Tom @ Nov 20 2007, 11:48 AM) [snapback]101556[/snapback]<div class='quotemain'>
Well the 5 and 4 cylinder weight limit happened to be the same for the 990's. Real convinient for Honda because apparently all they needed to do was add a cylinder to the RC45 engine and they were laughing.


RC45 engine? That was a limited production bike aimed at WSB. Why limit yourself to an existing, and aging, WSB engine design? Honda could surely afford to design the RC211 MotoGP engine from scratch...

<div class='quotetop'>QUOTE(J4rn0 @ Nov 20 2007, 02:23 PM) [snapback]101579[/snapback]<div class='quotemain'>
RC45 engine? That was a limited production bike aimed at WSB. Why limit yourself to an existing, and aging, WSB engine design? Honda could surely afford to design the RC211 MotoGP engine from scratch...


Its always better to start with something you already have data for, even if the finished product strays far away from the starting point. Thats why Kawasaki started their project with a modified zx7r chassis and why yamaha tried to stick with the frame from the old 500, and used carbs.

<div class='quotetop'>QUOTE(Tom @ Nov 20 2007, 11:48 AM) [snapback]101556[/snapback]<div class='quotemain'>
Well the 5 and 4 cylinder weight limit happened to be the same for the 990's. Real convinient for Honda because apparently all they needed to do was add a cylinder to the RC45 engine and they were laughing.


The RC45 twist was new to me, but multi-cylinder is expencive and Honda was the only one exploring the 5-cyl alternative and as you said it was conviniently regulated to the same weight as 4 cylinder. RPM = power and a 5 cylinder should easily become more powerful than a 4 cylinder and it was.
What I did hear was that going to 800 Honda wanted to base their enigine on the 5 cyl RCV211 by removing one cylinder, at the same time closing the door for any 5 cylinder 800cc with increased weight for that configuration.

<div class='quotetop'>QUOTE(Tom @ Nov 20 2007, 03:57 PM) [snapback]101585[/snapback]<div class='quotemain'>
Its always better to start with something you already have data for, even if the finished product strays far away from the starting point. Thats why Kawasaki started their project with a modified zx7r chassis and why yamaha tried to stick with the frame from the old 500, and used carbs.


'Adding a cylinder' sounds simple but involves really a major redesign - certainly a brand new crankcase and lubrication system, new and longer shaft... In the end what is left of the 'original' engine? They could have used the same cylinder-head units but I doubt the RC45 cylinders, pistons and heads were up to the MotoGP requirements in 2002.

The RC45 developed 118HP and the MotoGP engine 225HP. I guess the extra cylinder that added the 100+HP was a really large one ?

<div class='quotetop'>QUOTE(crvlvr @ Nov 20 2007, 11:47 PM) [snapback]101657[/snapback]<div class='quotemain'>
The RC45 developed 118HP and the MotoGP engine 225HP. I guess the extra cylinder that added the 100+HP was a really large one ?

KTM are still developing the 2 stroke, see the 300EXC for example.

They are experimenting with fuel injection on the two strokes...

<div class='quotetop'>QUOTE(RCV600RR @ Nov 21 2007, 04:20 AM) [snapback]101680[/snapback]<div class='quotemain'>
KTM are still developing the 2 stroke, see the 300EXC for example.

They are experimenting with fuel injection on the two strokes...


Sure, both they and Aprilia are developing their engines but it's not like there are huge spendings on motorbike 2-stroke engine development world wide. If it was the development would have been faster.

<div class='quotetop'>QUOTE(Babelfish @ Nov 21 2007, 05:00 PM) [snapback]101757[/snapback]<div class='quotemain'>
Sure, both they and Aprilia are developing their engines but it's not like there are huge spendings on motorbike 2-stroke engine development world wide. If it was the development would have been faster.

That's because the 2-stroke is "seen" as being impossible to make clean.

Actually Orbital in the 90's with their direct injection engine were getting as good results as 4-strokes of similar power.

The only thing that will always be "negative" (I personally disagree 'cos I love the sound) about 2 strokes is the fact that the frequency of the noise they produce is similar to human speech and so they sound "louder" then the dB reading implies.

Technology could have found a way to make strokers just as clean and efficient as the latest 4-stokes (remember a lighter engine will translate to more mpg) but opinion (not engineering facts), has made the 2 stroke an undesirable beast. Honda's dislike of them was a final nail in the racing fraternity coffin - hence it was not worth wasting the research on for road use - car or bike - by any manufacturer.

<div class='quotetop'>QUOTE(yamaka46 @ Nov 21 2007, 10:29 PM) [snapback]101796[/snapback]<div class='quotemain'>
That's because the 2-stroke is "seen" as being impossible to make clean.

Actually Orbital in the 90's with their direct injection engine were getting as good results as 4-strokes of similar power.


What is this orbital thing? A two stroke vankel?
And does it have anything to do with a piston engine?
<div class='quotetop'>QUOTE<div class='quotemain'>
Technology could have found a way to make strokers just as clean and efficient as the latest 4-stokes (remember a lighter engine will translate to more mpg) but opinion (not engineering facts), has made the 2 stroke an undesirable beast.


While the outboeard market has shown development promise on the two stroke it's hard for me to belive that it can get clean. It has huge inherent disadvantages as it rely on fresh gas to spool out the exhaust. It's hard to see how they can make that efficient.

<div class='quotetop'>QUOTE<div class='quotemain'>
Honda's dislike of them was a final nail in the racing fraternity coffin - hence it was not worth wasting the research on for road use - car or bike - by any manufacturer.


Well, when everyone has left it for dead, there is allways the slight possibilty that they do it for the most obvious reason; it had no future.
The guys researching this knows an awful lot more about engines than we do so just maybe they did just the right thing.

Besides, if someone outsmart the difficulties I see no reason why it shouldn't come back.

<div class='quotetop'>QUOTE(Babelfish @ Nov 22 2007, 11:11 AM) [snapback]101816[/snapback]<div class='quotemain'>
What is this orbital thing? A two stroke vankel?


Don't worry Babel .....the orbital was an engine from the 70's here in aust. It was never a high performance engine, it was a compact engine ... thast as far as it got.... the best thing about it was Sarich managed to sell "the idea" to Ford

I think a lot of Sarich's ideas have made it to outboards though ....??