2-strokes in MotoGP?

[mr bucketracer]

i like all racing . i don't care if 2 stroke or 4 . as long as engine size is done fairly ! to race them together

[Dave-]

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

ok you win.

[husaberg]

Most of the stuff i posted wasn't that pop culture yes it was dummed down for the masses but as Dave_ has said, there is plenty of info out there.
What i was trying to show was injected 2 strokes were about in gp500's.Honda were doing lots 2 stroke research

I don't think direct injection can compete HP wise with injection or carbs for direct HP. but it can make emissions tolerable with decent HP.
Fletner is doing some clever stuff with some basic car components and getting great results.

Shit even Honda said indirect injection gave them no more power just 5-10% better fuel consumption.

Anyway here is some stuff.http://engineringcorner.blogspot.co....ke-engine.html

Hoda weren't going out of thier way to advance 2 stroke technology were they?

no only into 4 strokes..........


http://www.cycleworld.com/2012/08/13...-resurrection/

In addition to direct fuel injection, there are other technologies that can help. Two decades ago, Honda introduced a 250cc, two-stroke motorcycle engine for a Japanese-market-only dual-purpose bike that utilized “Activated Radical Combustion.” This is a technology that has since been well-studied by the automotive industry and is more commonly known as HCCI (Homogenous Charge Compression Ignition), a combustion process that requires no spark but uses gasoline rather than diesel fuel. In Honda’s 250, HCCI combustion was maintained from about eight to 50 percent load, with conventional spark ignition used at both the high and low end of the engine load range. The benefit was far more stable combustion (no six- or eight-cycling) when HCCI was operating, lower emissions and—according to those who rode it—a two-stroke that felt as if it had the smooth power of a four-stroke. Honda’s patents have since expired.

CRM250 AR 1996 - 1999 And this is where it all stopped. Honda like all manufacturers were under increasing pressure from the USA and it's own country to clean up it's act and this is the first and only production bike that used Honda's development "Active Radical System". The "Active Radical System" or AR as it was known was a clever way to reduce emmisions from the unfreindly 2 stroke engine while giving more low down grunt at the same time. To ride a AR for the first time is quite odd. On the over-run it feels more like a 4 stroke engine and almost feels like the ignition has been cut, yet as soon as the throttle is opened up it kicks straight back into life. The AR models are very different not only in the engine area, but also the ignition and carburation, And features many electronic pickups and sensors to give the maximum burn with maximum efficiency. Dont let the style fool you with a Mk3 as the frames and motor are not interchangeable. Regarded by many as the Ultimate CRM250.
Prices are quite high for this model, and older well used bikes go for around £1400+ while the latest low mileage bikes are still changing hands for as much as £2200.http://www.crm250.com/history.asp

http://dwolsten.tripod.com/articles/jan97.html

For those who dont know, the CRM250AR was the production version of the EXP-2 Enduro prototype that used Active Radical Combustions to decrease emmissions.
The bike at low revs and low throttle openings closes and exhaust flap (hondas fancy word por PV) and introduces hot exhaust gases back into the cylinder to become thousands of tiny spark plugs (known as Active Radicals).
Therefore the Spark ignition is no longer required, the engine 'diesels' as it undergoes controlled detonation combustion.
When Undergoing AR combustion the engine purrs steadily without the expecting 'ring-ding-ding' unsteady combustion cycles common in two strokes. its almost akin to a four stroke.
Crank the throttle open and the engine comes to live with potency close to a CR250 honda.

Some EXP stuff
http://www.motorcycle.com/manufactur...xp2-15170.html

[husaberg]

This is some stuff i just found on a troll.

DI may have been banned although i think it was only indirectly banned (no fuel injection pressure above 10 bar is the current rule)
Note Dave Honda didn't get their way with getting the FIM to allow them to race the 250 Turbo esp note the HP

[F5 Dave]

That was 1985. Things change.

+ also they were probably peeping over the fence at F1 & Turbo madness that was going on (or so I understand, I never followed cars).

[mhbarber]

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.

thank you; for being the only person to (half(ish)) answer my question.

[husaberg]

Never seen the question, but considering the gains Aprilia made per year for HP given and given fair formula for 2 stroke vs 4 stroke.
The 2 stroke almost always wins for Gp racing...........

[F5 Dave]

thank you; for being the only person to (half(ish)) answer my question.

How did that answer your question knobend?

how about Aprilia RS 125 54 hp. x4 but with only one gearbox loss.

but also with a better soundtrack than the diesels.

[Dave-]

How did that answer your question knobend?

how about Aprilia RS 125 54 hp. x4 but with only one gearbox loss.

but also with a better soundtrack than the diesels.

Clearly because my post was so insightful!

I'm gonna miss access to journals when I leave university

[F5 Dave]

I just cant imagine he read any of it & is pretending to be a smarty. He needs a smack. I'd give him one next time I see him, but I'd need a stool & there's never one handy

[dangerous]

How did that answer your question knobend?

how about Aprilia RS 125 54 hp. x4 but with only one gearbox loss.

but also with a better soundtrack than the diesels.

yeah na... but Dave, is that a single or twin crank RS and would you call it a radial or V single?

but I'd need a stool & there's never one handy

well... do what a few cantabs did a couple a years back and dump ya stool in a bag, take it with ya till you see him...


or use a paper bag and set it alight at his door...

[F5 Dave]

Wrong kind of stool, but I like your thinking. Actually might be easier to get thru Aussie customs. Find THIS in your cavity search mate. I can make a new one.

[mhbarber]

& I bet they didn't. I am 80% certain it wasn't permitted by the rules.

The FIM were set to stiffle further development of the 2 stroke as they were going through the throws of the bikes power outweighing the tyres. Hence the incremental increase of minimum weights & keeness to adopt highly toxic unleaded gas.

And also they were a bunch of short sighted fuckers who were in love with the old days of MV & Norton & decided if you can't beat em, - give the alternative a 2x capacity advantage.

No direct injection development so no advance in technology & road spinoff hence no appetite to race 2 strokes.

never let facts get in the way of a good rant.
Honda are in the business of making money; the writing was on the wall with our beloved 2-strokes, so they - and the other manufacturers - touted the change to 4-strokes.

[husaberg]

never let facts get in the way of a good rant.
Honda are in the business of making money; the writing was on the wall with our beloved 2-strokes, so they - and the other manufacturers - touted the change to 4-strokes.

Funny enough the movement started in about 94-95 Cagiva had just left to build the F4 leaving only Yamaha Suzuki and Honda to play in the 500's.

The WSB at the time (Flamini) had Ducati Kawasaki Honda yamaha, with Aprilia Harley Davidson and Cagiva all expected to join.
Then (Dorna i think it was who ran it) GP introduced the 600's thunder bikes for a bit of entertainment.

At the time Superbikes were far more of a spectacle and were drawing big audiences and revenue, and getting bigger and bigger every year.
This was starting to affect the GP incomes purses.
With the WSB The racing was close even if the lap times were slower than the 250 gp bikes.
Racing for most spectators is actually about entertainment.
We are all bike nuts and forget that, well i do anyway.

My last post i missed something else.

Please take the time to read it.
The same thing happened (with F1, same guy) "It's all about making it more Professional".......................

add in the Pay TV money and so on...............price for admission goes up so on..........

Far to many noses at the throughs.

Added the BMS851/985 cause i like it, and there is F-all pics on it on the Web. Is it still at BMS Dave.

here is the Formula a couple of boffins hired by thr FIM came up with for 2 vs four stroke.
http://www.kiwibiker.co.nz/forums/at...9&d=1356318463

seems pretty fair to me 360cc vs 500cc or 500cc 2t vs 694cc 4t shit give them 750cc i don't care

[eelracing]

never let facts get in the way of a good rant.
Honda are in the business of making money;

Aye that is true,but the true rot set in when Dorna gave the manufacturers association the free agenda to set their own technical regulations.With the promise from said manufacturers that they would guarantee enough works and customer bikes.You can see how well that's worked out eh.

Every man and his dog knew costs would skyrocket and eventually only the manufacturer with the most resources would prevail.
Honda must be laughing all the way to the bank.