2-strokes in MotoGP?

[mr bucketracer]

l can't think of a 2 stroke road bike from 1990 that benefited 500 gp technology, even years well before that

[F5 Dave]

The point was they were fighting emissions from well before the last hurrah and 500s had stagnated for many reasons, potential not being one of them

[mr bucketracer]

The point was they were fighting emissions from well before the last hurrah and 500s had stagnated for many reasons, potential not being one of them

thats it . in a nut shell a 500 2 stroke uses the same amount of fuel as a 1000 four stroke and that because a 4 strokes fire half as much , lasts way longer , better controllable power, and still better on fuel , most bikes on the road are 4 strokes , most cars are 4 four strokes apart from the odd old dog . so can see why they did what they did.

[Drew]

thats it . in a nut shell a 500 2 stroke uses the same amount of fuel as a 1000 four stroke and that because a 4 strokes fire half as much , lasts way longer , better controllable power, and still better on fuel , most bikes on the road are 4 strokes , most cars are 4 four strokes apart from the odd old dog . so can see why they did what they did.

A forced induction, direct injected two stroke would have the same emissions as a four stroke. Capacity not withstanding of course.

The power could then be made controllable, and reliability just as good.

The system would, simply put, be more efficient all round.

[mr bucketracer]

A forced induction, direct injected two stroke would have the same emissions as a four stroke. Capacity not withstanding of course.

The power could then be made controllable, and reliability just as good.

The system would, simply put, be more efficient all round.

so why did they not do it ?

[husaberg]

Actually I thought I had read that was one of the reasons Bimota flagged development of a GP bike because DI wasn't allowed.

Honda didn't test DI in GPs did they? - no they tested conventional in 2 races (obtaining fastest speed for quite some years).

Hoda weren't going out of thier way to advance 2 stroke technology were they? They wanted to race 4 strokes, just they couldn't on equal terms (NR500 anyone?)

Capacity was 990 vs 500 at the start, 800 was some years later well after 2 strokes written out of the rules.

No they (honda) didn't test DI in GP's as far a i know cause as i said and will say again it makes less power than indirect injection or it did then.
You said they never tested it maybe other than the EXP...... (which is obviously incorrect) i disagreed and was totally correct.
The fact that Bimota developed the DI for GP proves me more right unless they never bothered to read the rules..........
Honda were out to advance 2 stroke technology (when it suited them) Case reed for instance was on the RC125 years before Suzi...
Atac Herp RC valves water injection, fuel injection etc.
The EXP was a total 2 stroke technology showboat... (a corporate wank session)it was its only reason for existence....
Honda gave up on the NR then built the NS500 and were hugely successful building something different. reed 3 vs disk 4 but from memory with the NR Spencer did put it on pole at its last outing and won a race on it.Think it was non GP though.
The NR was also a show off of what they could build look at the rads the Forks the Carbon fibre.......


Re you saying it only had 2 outings on the duel injected NSR500 Itoh raced it for a season 93 (the article mentions he only did 2 races in 94) bar a couple of rides on Doohans bike when he was injured (Itohs best results were on a Doohans Carb bike though)

Remember that Yamaha killed the open MX with their want to build a Foul stroke...... People brought them in droves other manufacturers followed suit.

[husaberg]

so why did they not do it ?

Forced induction was only allowed half the capacity......
Honda did build a 250 turbo 4 stroke for Spencer to race in the 500 class that made incredible power. Not sure if it was actually raced but it was built...
Someone mentioned the Power of a 12a i say BS...... unless it was on funny fuel and blown........
The FIM rates rotary as 2x the swept.
Norton was effectively a 1100 racing against 750's cause they bent the rues in Blighty(to suit the Norton)
It still was pretty as was the 92 Honda.

[slowpoke]

um. . .I struggle to see the relevance of your point. No really. You're talking entirely about diesils in a 2 stroke related thread.

My bad, I thought you mentioned road spin off's, and MotoGP.......oh wait, you did. My point was that what we see in MotoGP does not automatically translate to the road and that road bikes can and have developed quite well without MotoGP. Same would apply for any 2T tech in your alternate reality if you stopped to think about it.

I was of course talking about the development of the DI 2 stroke. If it was raced there would be development. Its a different technology, not a progression of a roadbike.

Spin off could have been DI NSR250 et all & potentially larger capacity bikes again once emissions could be reined in which was the stumbling block and why 2 strokes disappeared from the road in diminishing engine sizes. if allowable emmissions for a vehicle is x amount then a 125 spewing 10% out is half the amount of a twin 250.

DI is all well and good in theory but it isn't the magic bullet for 2T's, have you thought about the effect of fitting catalytic converters to a 2T? DI alone isn't going to be enough to get them anywhere near increasingly stringent emissions testing regimes. And with 2T's extremely exhaust sensitive it ain't gonna be easy....imagine having to package 4 x cat's on an RZ/RG500.

[Drew]

so why did they not do it ?

Dunno. It's worked for ages in diesel applications.

Forced induction is frowned apon in racing, outside of rally for some reason.

[Drew]

DI is all well and good in theory but it isn't the magic bullet for 2T's, have you thought about the effect of fitting catalytic converters to a 2T? DI alone isn't going to be enough to get them anywhere near increasingly stringent emissions testing regimes. And with 2T's extremely exhaust sensitive it ain't gonna be easy....imagine having to package 4 x cat's on an RZ/RG500.

That's why I said forced induction. Control the inlet and exhaust with valves, and the exhaust all of a sudden can be just like that on a four stroke.

[husaberg]

That's why I said forced induction. Control the inlet and exhaust with valves, and the exhaust all of a sudden can be just like that on a four stroke.

Go back and read Honda has done it with a Converted 4 stoke already......
Click on the arrow Drew.

Some stuff in the text from memory was wrong but what the hey........

I hate trying to read the articles like that. Does nothing good for my eyes.

then click and click again until the plus with the magnifying glass appears then click again they will blow up huge bigger than full screen about 4x full screen.

Lastly this is how cheap the 500's were to run until they got "lifed" out by the increased output Honda made Yam go to later.

See above and below for the cost of running the Yamaha latter on. Until they were made available by Yama at Kenny request ya were either a works rider or had an old old RS500 and finished a lot of laps down.........

[Drew]

Go back and read Honda has done it with a Converted 4 stoke already......

I hate trying to read the articles like that. Does nothing good for my eyes.

[husaberg]

Last of the Yamaha privateer stuff has the costs of running etc.

[Dave-]

Couple of Journal articles and thesis papers I just pulled up:

Development of a novel uniflow-scavenged two-stroke gasoline direct injected engine
Thermodynamic analysis of supercharged fuel-injected two-stroke cycle engines
Direct injection of hydrogen, oxygen and water in a novel two stroke engine <-- fucking cool
Exhaust emissions of low level blend alcohol fuels from two-stroke and four-stroke marine engines
Advanced modern low-emission two-stroke cycle engines
Study on manifold injection of LPG in two stroke SI engine.

Here's a couple you guys should be able to view:

Control of Exhaust Emissions from Copper Coated Gasohol Run Two Stroke Spark Ignition Engine with Catalytic Converter
http://www.ccsenet.org/journal/index...cle/view/12104

Fuel Injection Pressure Effect on Performance of Direct Injection Diesel Engines Based on Experiment
http://www.doaj.org/doaj?func=openur...ue=3&spage=197

Put down those poppy magazine articles and read something with a bit of substance. I'd crack through all eight if I didn't already have 20 ECU and data acquisition papers to read through....

edit: Fuckin' hell the English in that 2nd one is a bit wobbly.

[husaberg]

Couple of Journal articles and thesis papers I just pulled up:

Development of a novel uniflow-scavenged two-stroke gasoline direct injected engine
Thermodynamic analysis of supercharged fuel-injected two-stroke cycle engines
Direct injection of hydrogen, oxygen and water in a novel two stroke engine <-- fucking cool
Exhaust emissions of low level blend alcohol fuels from two-stroke and four-stroke marine engines
Advanced modern low-emission two-stroke cycle engines
Study on manifold injection of LPG in two stroke SI engine.

Here's a couple you guys should be able to view:

Control of Exhaust Emissions from Copper Coated Gasohol Run Two Stroke Spark Ignition Engine with Catalytic Converter
http://www.ccsenet.org/journal/index...cle/view/12104

Fuel Injection Pressure Effect on Performance of Direct Injection Diesel Engines Based on Experiment
http://www.doaj.org/doaj?func=openur...ue=3&spage=197

Put down those poppy magazine articles and read something with a bit of substance. I'd crack through all eight if I didn't already have 20 ECU and data acquisition papers to read through....

edit: Fuckin' hell the English in that 2nd one is a bit wobbly.

Err i haven't posted the SAE articles as i, well won't..........