End Of The 2 Stroke?

[dadof2]

I was at a motorcycle (road bikes mainly) dealers a few days ago and with regard to small commuter bike he said these were the last batch of 2 strokes he was getting. Manufacturers were going 4 stroke only because in many markets catalytic converter would be required from 2016 for motorcycles type approved for road use / registration.

He did not have any legal info in particular or if this would apply to UK or EU, he just assumed it would based on what manufacturers supplier had said.

Anyone else heard anything?

[0007]

Were these bikes Scooters from China or Taiwan?, I don't think any Japanese brands build street able 2 strokes anymore

Emissions is going to kill off low tech 2 strokes for sure in pretty much all non third world countries, it's just a matter of time

It's a simple money thing, it's possible to make a 2 stroke clean but it needs fairly expensive EFI or DI technology precious metals in cat's etc and modern expensive 2 stroke oils

4 strokes are much less expensive to make compliant, the most basic old tech fuel injection tech works and they don't run a total loss oil system so they are way ahead right from the beginning

[dadof2]

Yes they were Lifan, scooters and small motorcycles but some are badged differently. In General the 4 strokes are Honda copies and the 2 strokes Yamaha copies.

You find Lifan engines in just about anything from wackers, generators, buses, cars and trucks.

[telecat]

Have a look at the Norton Villiers Website.

[dadof2]

Telecat - was NV website for general interest or is there something specific to my original post - is so please provide a link to the page

Thanks

[cactusjack]

Husqvarna released the WR300 models into Australia with Catalytic Converters in the chambers, the first thing we did at pre delivery was to get rid of them and put an open chamber on them. We never even tried to run them in the Euro3 mode as they probably wouldn't be rideable. 2 Stroke fuel injection will move forward and I think that it will become viable financially, it will just take time.

Edited February 5, 2014 by cactusjack

[0007]

There are lots of fuel injected 2 strokes on the market, problem is fuel injection systems are most often patented and the rights are bought by manufacturers, they are tied up

The other issue is EFI just replaces a carb, it simply more precise, it does not fix a fundemental problem in that the exhaust port is wide open for a period of time and fuel mix just leaks out

EPA keeps getting stricter as well so time is an enemy

So they need Direct injection and that takes lots of fuel pressure, high pressure pumps, powerful battery and stator and a drastic change in the design

So it means expensive rocket science that is prone to warrantable failure, manufacturers don't like warranty

It's not easy to make clean 2 strokes in a light compact package like a bike

[totty79]

I don't think direct injection has any greater electrical requirements than standard injection if a mechanical high pressure pump is used. I don't know the ratio between mechanical and electrical pumps out there but the Vauxhall 2.2 direct engines definitely use a mechanical high pressure pump - the warranty argument fits this example as the first generation of pumps and regulators on these engines were mostly replaced under warranty.

DI addresses the fuel loss out the exhaust but the lubrication system still needs to be addressed.

[tony27]

Pretty sure that direct injection is still banned in FIM competition which would prevent any manufacturer doing any serious development on anything other than commuter bikes.

If memory serves me correctly the NSR500 that Ito raced in the 90s used a more basic system than fitted to the Ossa & it was far from perfect, the Bimota Vdue was developed with DI but ended up back on carbs when they didn't have the money to get the setup right

The best part of direct injection is that the fuel is injected after the exhaust ports/valves have closed which means none escapes down the exhaust which helps with both economy & emissions. I'm certain the Motogp teams would use it if allowed for the economy reasons & the manufacturers would have plenty of knowledge through their car making tie ups

[0007]

Dad was referring to streetable motorcycles in his original post

I think the reason racing applications don't use expensive technology like this is that they don't need it

EFI and DI were more to cleanup tailpipe emissions not necessarily to make more power

EFI is a benefit to a race bike as it allows single throttle valve fly by wire and a very short intake tract etc, there is a lot more precise control because of temp and altitude mapping too

But I wonder what a carb could do if Mikuni and Kei hin had never thought of EFI?

Edited February 11, 2014 by 0007

[telecat]

http://www.nortonvilliers.com/

The FITS engine.

[0007]

I couldn't watch the second vid there but it kinda just looks like it's a little supercharger, is it also direct injection?

[0007]

Ok watched both now, the second engine is 2 stroke with intake and ex valves and is supercharged, there is potential for that to be a clean engine aside from the fact that 2 strokes always run a total loss oil system

Problem: Expense, probably more expensive to produce than a 4 stroke, not to mention development cost would be pricey, cam needs to spin at crankshaft speed etc etc

The first engine doesn't give you enough info to tell anything other than it is supercharged

If it's direct injection it doesn't show a pump or anything, D.I. Takes hundreds of lbs of fuel pressure

The biggest joke about 2 strokes is that they are not required to run 2 stroke oil during EPA testing due to a loophole

[dadof2]

There are all sorts of things that can be done to a 2T to try to clean it up but all add cost and complexity to such an extent its probably easier just to use a 4T.

My concern is that some legislation will appear that makes it impossible to register 2T bikes for the rad.