KTM Debuts Fuel Injection for Two-Stroke Motorcycles

03/15/2017 @ 12:19 pm, by Jensen Beeler78 COMMENTS

The day has finally, come. The rumors can finally be put to rest. Fuel injection for production two-strokes is officially a thing, thanks to the clever minds at KTM.

The Austrian announced today that it will bring fuel injection technology (called Transfer Port Injection) to its 2018 enduro lineup, which will debut later this May.

Two KTM models will have the new technology, the KTM 250 EXC TPI and KTM 300 EXC TPI, and they will be coming to the global market. For the USA and Canada, a third model will come to market as well, the KTM 250 XC-W TPI.

Fuel injection for two-strokes promises better fuel consumption, and it means that riders no longer have to pre-mix their fuel. KTM says that its transfer port injection technology provides a whole new experience for riding a two-stroke motorcycle, with better power and rideability.

“This is an incredibly exciting development for KTM. We have been developing two-stroke fuel injection for some time and our goal was to create competitive motorcycles with all the benefits of fuel injection, while fitting into our READY TO RACE mantra,” explained KTM Product Marketing Manager Joachim Sauer.

“There has been extensive testing and considerations for our Research and Development team to take into account during this process, so we are very motivated by this next step and world-first in technology, as we take a major step forward in this segment.”

“We are certainly looking forward to unveiling the new 2018 KTM 250 EXC TPI and KTM 300 EXC TPI machines in May. In Europe the bikes will arrive at the dealer floors in early summer, and in the U.S. and Canada, the new 2018 250 XC-W TPI will be available in very limited quantities in late fall.”

Source: KTM

  • Superlight

    It will be interesting to understand how this system works versus the problematic Bimota 500 2-stroke FI design, but there has been a lot of electronics technology since then.

  • NortNad

    Wow!, big news & it meets Euro 4!? You cant beat the weight savings of a 2 stroke motor

  • Sam Miller

    You should ask KTM USA abut this. They disagree about the delivery date and won’t even talk about it any further.

  • Sam Miller

    Bummed it’s only TPI. Sad that outboard boat motors have cleaner tech than KTM’s latest and greatest. I’ve said for years I’m not replacing my ancient ’99 300 until they are direct injected. Good thing I just gave it a crank up rebuild, looks like it’s gonna be a while still…

  • n/a

    Why are KTM still developing two stroke off-road bikes?

  • Sam Miller

    For me!!!!

  • n/a

    Do they even supply engine components for your ’99 300 now?

  • There is still a very strong market for two-stroke bikes. It’s good to see the tech slowly coming into the 21st century too.

  • Jason Channell

    KTM has come to play some ball in the past few years. Holy (2)smokes!

  • n/a

    In the off-road sector? I’m struggling to believe that. Motocross racing all seems to be four stroke now. The only market for two strokes I can think of is enduro/’kids’ bikes(YZ80 etc.).

    Is that a big market?

  • Jeram Mallis

    This is a great debelopment. Transfer Port Injection works much better than both manifold injection and direct injection.

    Fuel consumption and emmissions drop rapidly as the fuel is injected late (just after BDC), as less of that later fresh change will be lost out the exhaust port.

    Throttle response is also greatly improved over both Direct Injection and typical manifold injection.

    The technology is well proven, being used previously by Polaris and more recent years by a two stroke engineer in New Zealand. He built a YZ250 and a 1970s Kawasaki Bighorn 350 using the technology and has successfully raced them for a number of seasons without issue.

    The biggest thing you’ll notice when the bikes come out is the sound. They are buttery smooth at lower RPMs. No more ting ting ting sounds.

  • David

    Two strokes are still hugely popular outside of racing.

  • arr2

    na,
    Go to an off road race, hare scramble, especially enduros and even dual sport rides. You will get tired counting the two strokes.
    Two strokes are a huge part of KTM’s business

  • pidgin

    I just hope this is a wake-up call for japanese to finally bring us 300+cc dual-sports/supermotos.

  • Ross Weitzner

    20 years, in fact…

  • mikstr

    I truly doubt it meets Euro 4. This sounds like the a similar tech to what has been used in snowmobiles since 2004 (“semi-direct injection” launched by Rotax with the 600 HO SDI) and, while a definite improvement over a conventional two-stroke, it definitely is not clean enough to meet the strict Euro 4 standards (not sure a DI two-stroke would be capable of meeting those).

  • mikstr

    because some like light and powerful bikes that don’t cost an arm and a leg to maintain….. recall reading that their 250cc two-stroke is their most popular engine… seems many have not been swayed by the camshaft revolution…

  • mikstr

    nothing new here, been in snowmobiles since 2004…. in fact, sledders even have DI two-strokes now (since 2009)

  • mikstr

    No big surprise, considering they changed the rules (gave the 4-strokes such an overwhelming displacement advantage) to basically kill off two-strokes

  • keithwwalker

    It sounds like the key issue is that KTM is injecting the fuel in the transfer ports – after the crankcase. BiMoTa, afaik injected before the crankcase.

  • keithwwalker

    Not buyin’ til street legal.

  • darren636

    best answer ever

  • Sam Miller

    Most

  • sigsegv

    It is Euro 4 compliant :)

  • LabRat

    LOL, the ITALIANS had Ditech by Aprilia in the 80’s

  • LeDelmo

    Its about freaking time. They have been sitting on this for so long.

    So, how does KTM’s Fi differ from those used in bikes like Beta?

  • LeDelmo

    Because 2 strokes are far superior to 4 strokes for Enduro riding….
    And Fi 2 strokes are still better yet!

  • teanayu

    Direct injection supercharged 3 cylinder 600 please

  • paulus

    It is Euro 4 compliant. EXC are road legal machines…. there is a concern about meeting the upcoming Euro 5.. but there are a couple of years to reach that goal.

  • paulus

    Most off-road bikes never hit a track… trails and enduro riding. In tight woods there is not much better than a 2 stroke (I ride a big thumping 4 stoke… but know when I there is a better tool for the job).

  • paulus

    300cc… the king of KTM’s/Hunsky’s Enduro 2 stroke range

  • paulus

    Not sure about the US… but for Euro, this is street legal at Euro 4

  • paulus

    1. Because there is demand
    2. Because few others are offering it (they can be the market leaders)
    3. Because, with the right technology 2-strokes are a good choice

  • mikstr

    there is NO WAY this is Euro 4 compatible……

  • mikstr

    Not a chance. Four-strokes are having to be massaged to meet the standard, there is no way that a semi-direct injection two-stroke will meet it. This technology has been around in the snowmobile world for almost 15 years now and while it’s a definite improvement over so-called conventional two-strokes, they still smoke and emit not-insignificant levels of unburned hydrocarbons. Again, there is NO WAY these are Euro 4 compliant.

  • mikstr

    Beta’s system is just a throttle body injection (ie. injector located in throttle body; allows more precise fueling and thanks to computer, can automatically compensate for altitude and atmospheric pressure changes) whereas this has pure air going into the engine with fuel injected into the transfer ports. When timed properly, it significantly reduces unburned hydrocarbon emissions and fuel consumption. A similar system is used by Polaris in the Cleanfire snowmobile engines. Arctic Cat also have a neat variation of this with its C-TEC2 dual-stage injection technology.

  • mikstr

    DI engines idle uncannily smoothly but TPI engines (or semi-direct injections, as they are known in the snowmobile industry) still “hunt” at low-rpm (ie. emit ting-ting-ting) though not as badly as a conventional carbureted two-stroke.

  • DiscoBallz

    It is street legal in the US. Easy to title for the street in most states for any of KTM’s dirtbikes. Put a headlight and tail light on if it doesn’t come with and you are good to go. Supermoto commuter anyone?

  • EricBanana

    Betas still use traditional carburetors (the enduro range has oil injection meaning you don’t need to premix the fuel)

  • mikstr

    which was basically Orbital technology

  • MikeD
  • MikeD

    I fail to see how this is BETTER(cleaner-more efficient-smoother running) than DI specially on a 2-Smokes. Enlighten me. My experience has been a Kawasaki STX1100 DI. Smoothest, cleanest running 2 stroke Triple i have seen (haven’t had a chance to check Evinrude’s E-TEC system yet or SkiDoo sleds.).

  • MikeD
  • MikeD

    2 Words: Erzberg Rodeo.

    Almost everyone uses a 2 stroke. I wonder why ?

  • MikeD

    Yup, I thought they would go str8 up D.I. from the get go.

  • MikeD

    It’s no Evinrude E-ETEC or Ski Doo 800 D.I but at least it’s a step in the right direction. ABOUT FRIGGIN TIME, KTM, thanks for at least bothering to do it . . . hopefully the “others” will follow and someone will finally bring D.I.

  • dcopperfield

    Motocross racing is four stroke because of regulations limiting selling two-strokes. No one has invested in updating two-strokes in a long time. If KTM sales are successful, others may join in. The technology is available to make a cleaner two-stroke. And two-strokes sure are good for dirt bikes.

  • azboy

    If it proves successful, and I’m sure hoping it does, and it leads to the return to the days of the NSR, TZR, and RG’s…..I’m really pulling for these guys. Of course Honda will stick to it’s misguided 4 stroke principles, so maybe not so much the NSR…..

  • Jeram Mallis

    Di is no good for this application.

    Throttle response with DI is absolutely rubbish.
    On Boats, jet skis and sleds throttle response matters much less than on a bike. On a bike, throttle response is critical.

  • Frollet

    Probly runout injection in the crankcase like road bikes did for reliability and service life and other then that it’s pretty basic

  • Ville Äyräs

    Cause light is right.
    Weight is your enemy.

  • n/a

    How many participants in it?

  • MikeD

    YouTube it’s your friend, look it up and believe your eyes, not some guy off the internet.

  • n/a

    I’ve seen it before, I’m looking for a figure to get an idea of the size of the market?

  • a tom

    I’m curious… any indication yet how significantly this may affect cost, both at time of sale as well as for maintenance (time included)?

  • mikstr

    You clearly haven`t ridden a DI (ie. E-TEC) sled to say such rubbish….

  • mikstr

    The E-TEC is much better than the Orbital design used by most (previously). No air pump, just a voice-coil injector that is quick and responsive…. works splendidly…

  • TR

    Off road racing/riding is still very much dominated by 2 strokes. The majority of people that ride off road regularly (not MX) ride 2 stroke. Much cheaper to maintain, and lighter in the woods.

  • TR

    1500 entries give or take.

  • TR

    Beta and Sherco have been developing the 2 stroke to some degree since 2013 at least. They both brought about the change in electric starting that KTM has now adopted by putting the starter on the bottom of the motor rather than on the side. The electric start on all of them is very reliable and starts almost instantaneously. Sherco doesn’t even put a kick start back up on theirs anymore. Beta now has oil injection so no more pre-mix, just add oil in a tank and gas in the fuel tank and go. Has 2 warning lights to make sure the system is still mixing.

  • TR

    I have a Beta 250RR Racing Edition 2 stroke and it’s street legal. I’m in Tennessee, but the title just says motorcycle, not off road only. It came with working headlight/taillight, wired for turn signals, and a horn. The EXC for KTM is their street legal designation.

  • michael uhlarik

    This

  • keithwwalker

    There’s a big difference in manufacturer street legal and pulling the wool over the eyes of a state DOT. I have a CR500 with a plate, but I want an emissions passing 2 stroke that is legal off the showroom floor. Nothing in the article is saying that is is passing emissions in the US or Europe. Please cite your reference that it passes Euro 4.

  • Axel

    Now, can I have this engine in the 390 Duke (road legal) and RC 390 (race only) frames? Pretty please, KTM?

  • MikeD

    Ah, i happen to be the wrong person but guesstimating by racers and spectator #’s i would say a good 1000+/- just at that event. Almost every racer was running a 2smokes.

  • MikeD

    The system Kawasaki used(poached off someone, not theirs) it’s a bare bones E-TEC setup(HUGE injector solenoids working at ~48v and backed by a huge capacitor too). No wonder it ran like a scalded cat in a rug.

  • mikstr

    Sounds like Kawi’s was an offshoot of the Ficht technology; E-TEC is greatly superior to that….

  • MikeD

    That’s exactly what it was.

  • paulus

    The death of the 2 stroke MX racer was two fold. The race classes and consumer demand. 250 2-strokes had to race 450 four strokes… the 4 strokes had the advantage, racers chose 450’s. Consumers of the time demanded four strokes, these were easier to ride, compared to the 2 strokes of the time (but admittedly much more difficult to start). 4 strokes stated selling well and luring riders back into off-road. Sales grew. 2-strokes were not the hot item anymore and development dollars went into 4 strokes. the Japanese brands started dropping 2 stokes over the years, with the exception of Yamaha. KTM and other European brands stayed the course and continued to offer 2 strokes. KTM developing its range and offering push button on its 2 stroke (and 4 strokes) for a long time now… making riding an even more pleasurable experience.

  • paulus

    check all the press releases….
    All state “Euro 4 compliant”… all state “KTM” as the source.

    “This is key because in some global markets, KTM still sells street-legal 250 and 300 two-stroke dual sports, and this new EFI unit allows those bikes to meet the very strict Euro 4 emission standards.”

  • MikeD

    WOW, WOW THERE . . . baby steps first, lol.

  • Benji

    Here in Canada we have a unified 250 class for MX too.

  • keithwwalker

    Yes, I saw that after I posted. (Note to webmaster: post your press release links)
    This is very, very promising. If you look at US emissions, in this case, we can benefit from the ‘Harley’ Tier 2 emissions, which allow for a very high CO limit relative to Euro 4 – this lets Harley still sell air cooled motorcycles. In fact, Euro 4 limits across the board are more stringent. It seems that a manufacturer certified street legal two stroke is a possibility in the USA!!! Now if KTM would only make a V-twin 500cc model sportbike!
    http://transportpolicy.net/index.php?title=US:_Motorcycles:_Emissions

    http://transportpolicy.net/index.php?title=EU:_Motorcycles:_Emissions
    (L3e is for motorbikes)

  • keithwwalker

    Here’s the article where KTM’s speaks of meeting Euro 4 regulations, No explicit statement that they do, but the have so many 2 stoke enduros that have to meet the regs, they must make it work
    https://issuu.com/enduro21.com/docs/enduro_illustrated_16/106

  • keithwwalker

    I want a baby step that looks like a BiMoTa V-Due – 500cc.
    Next baby step: 750cc sport bruiser
    I’ve waited long enough

  • Kimberly Gresham

    Came here to say this. I had an Aprilia 2-stroke SR-50 with direct fuel injection. The model got this option in 1999.

  • DR N

    Its about time outboard motors have had this technology for 10 years !