[Anand]

Austrian motorcycle major KTM has introduced a twist to 2-stroke technology. A 2-stroke engine is known to be extremely free revving, but also comes with its drawbacks like higher emissions and higher fuel consumption. KTM has attempted to address the issues inherent to such designs with the introduction of fuel injection to its Enduro range of motorcycles.

The company's 2018 model line-up will feature the technology, dubbed Transfer Port Injection (TPI). This method of delivering fuel and lubricant to the cylinder would eliminate the need for pre-mix fuel and carburettor jetting. The fuel consumption is also expected to be reduced. Developed in-house at KTM's R&D facility in Mattighofen, Austria, this technology represents a major step for pre-mix motors for both - on track and on streets.



In a recent interview, Mr. Joachim Saucer mentioned that the bikes will be tuned to perform similar to their carburetted counter parts. World over, the first among the KTM range to receive this upgrade would be the KTM 250 EXC TPI and the KTM 300 EXC TPI. The KTM 250 EXC TPI, will be introduced in the US and the Canadian markets.

Source: Paultan, RacerXOnline
Image: MotoOnline

[sudev]

Very interesting. 2 stroke are free revving as there is no valve train. Technically ok need not be premixed. Remember Yezdi King? Injection means lots of tuning possibilities

[Rehaan]

Wondering how this wasn't done before...

Some googling led me to this (possible) explanation:

This is the Ossa 300i fuel-injected enduro bike. It was developed in 2011, but was not sold in the USA. The injector is dead center in the photo. Ossa was bought by Gas Gas last year and Gas Gas declared bankruptcy and was sold to Torrot of Spain—no word on the fate of Ossa.

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Dear MXperts,
Why are the manufacturers that make two-strokes (KTM, Yamaha, Gas Gas, Husqvarna and TM), dragging their feet on putting fuel injection on their smokers. It would solve the jetting issues forever and produce even better bikes. What’s the hold up?

The first question is how much do you want the price of two-strokes to go up? The second question is how much weight are you willing to gain on your two-stroke? The third question is what’s so hard about changing a jet occasionally? The major manufacturers have fuel-injected two-strokes sitting in the R&D departments that could be released tomorrow if the world demanded it — but let’s not put our faith in the mob majority of the modern world. The current two-stroke is simple, light and relatively inexpensive. The reason that KTM, as an example, doesn’t want to fuel-inject their two-strokes, at this time, is because they will gain 5 pounds, the price will go up a couple hundred dollars and the consumer will not be able to cure his woes with minimal garage tools. KTM will offer fuel-injected offroad bikes in the future to meet the stringent new Euro-4 emission rules (as for now they have stopped selling 125cc two-stroke offroad bikes in Europe).

It’s important to note that fuel-injected bikes do not produce more power than carbureted bikes — just the opposite. What they do produce is a broader, easier to use and flawless delivery of just the right amount of fuel for the X’s and O’s of the ECU. And they will idle like a kitten. However, motocross bikes often need extra fuel for an upcoming situation and that is what a carburetor is great at providing. It doesn’t stream fuel electronically via a pump, it draws fuel in via the demands of the suction created by the engine itself. Carbs are true-to-life “on demand” fuel systems.

Read more: http://motocrossactionmag.com/news/a...ted-two-stroke

[Slick]

AFAIK, There is an Australian company called Orbital that has already developed and tested a FI system on Aprilia RS250, and this was ages ago.

The site went gaga over how the system improved the already fast RS even further, both in power & emissions.

I was expecting Aprilia to launch it sooner or later but didn't happen.

I figured either the system hampered the performance or was too expensive (Cost + Royalty) for it to make business sense. So Again I doubt Bajaj or KTM will have anything to do with this in India.

-Slick

[ecenandu]

Originally Posted by Slick

AFAIK, There is an Australian company called Orbital that has already developed and tested a FI system on Aprilia RS250, and this was ages ago.

-Slick

I had the opportunity to work on it(Bajaj auto), sadly the product was introduced in a half baked stage. A few more iterations would have ironed out the niggles but the major setback was the cost as you pointed out.

[rohitoasis]

Originally Posted by Slick

AFAIK, There is an Australian company called Orbital that has already developed and tested a FI system on Aprilia RS250, and this was ages ago.

In production guise the Aprillia SR50 ditech had this technology way back in the 1999.

A summary of the engine below.

Orbital came up with a method of injecting the fuel/oil mix directly into the cylinder head – the DiTech system – (as opposed to upstream of the valves in a fuel-injected four-stroke) and this breakthrough, combined with some sophisticated electronic engine management has revolutionised two-stroke engines. As an example, when I toured the Perth facility, Orbital engineers demonstrated that a DiTech engine would run quite happily on the emissions of a normal two-stroke. As an aside, the system also allows engineers easily to tune engines to various power curves to suit different applications.

I had fallen in love with that scooter back then. A 50 cc two stroke which could go top at 100+kmph as well as give four strokers a run for the money in mileage stakes.

Anyway, Aprilia chose engine characteristics that shocked the scootering world when the first model came out. I was lucky enough to ride one and found I could carry a comfortable 110km/h on a freeway – from a 50! Later models were detuned a bit to comply with various registration requirements, but the power was lurking, waiting to be released.

The upside of the retune came in fuel economy, with as little as 2L/100km claimed in fuel usage but, more importantly, up to 60 per cent less oil consumption – with service intervals of 12,000km. So that keeps the bureaucrats happy and puts more change in your pocket, but it’s still an expensive 50, right?

Link

Over the years i have come across many vehicles, but the sheer madness in the concept of this vehicle stood out for me. It took me a while to understand the working of this engine. But this unique engine even now remains in my memory and so does the image of the red and black scoot. (If i remember right it was a review in Auto India, if anyone remembers that magazine now.

Neither the speed or the mileage was the reason for me. It was the looks of the beauty back then that had me smitten. But then talking about beauty and Italians is something reserved for another forum.

[Sutripta]

Originally Posted by sudev

Very interesting. 2 stroke are free revving as there is no valve train. Technically ok need not be premixed. Remember Yezdi King? Injection means lots of tuning possibilities

If you mean the Oil King, it had a carburettor. And a metering oil pump, like every Jap 2Stroke in India.

Regards
Sutripta

[giri1.8]

Does this bring any good news to us? or will these machines remain for off-road use only in our country?

2-strokes are never good on paper but feel of riding one is a different story all together!

[Alfresco]

KTM getting the new 2-stroke bikes out in the market:

http://newatlas.com/ktm-2018-direct-...-enduro/49541/

"The two new enduros will start shipping in June. No pricing details have been released, but reportedly both EXC TPI models are expected to be in the same ballpark as their four-stroke counterparts."