Here are more details on KTM’s new fuel-injected two-strokes

KTM has announced more details on its new fuel-injected two-stroke off-road bikes.

Originally announced back in March, KTM’s fuel-injected two-strokes are firsts in the motorcycle world, although there have been other vehicles (personal watercraft, snowmobiles) sporting this technology in recent years.

There are two bikes with the new technology, a 250 and a 300 (North America will get the KTM 250 XC-W TPI). Both versions of the engine get KTM’s Transfer Port Injection, which works in a similar way to EFI on four strokes. At its most basic form, it’s just an injector spraying fuel into the intake, except that there’s a second injector in the throttle body that mixes two-stroke oil with the gasoline.

KTM says the new engine uses an 80:1 fuel-oil ratio; most modern two-strokes with carburetors have around a 40:1 fuel-oil ratio, so the new KTM technology significantly reduces the amount of tailpipe emissions. There are plenty of worn-out four-stroke thumpers that are burning more oil than that …

The 250 and 350 versions are exactly the same, except for engine displacement.

As said before, these bikes are off-road only, and KTM has made no announcements of street-legal versions. For now, don’t consider these machines a harbinger of a return to the glory days of two-smoke street screamers. If you want that sort of performance, you’d best keep looking for an RD350 or NSR250, at least for now.

Both the 300 and 250 versions of this bike use the same chrome-moly double-cradle frame, and weigh 103 kg.

Except for engine capacity, they are exactly the same, also sharing WP Xplor adjustable suspension and Brembo brakes. They are supposed to start shipping to dealers in June; no Canadian pricing has been announced at this time.

7 thoughts on “Here are more details on KTM’s new fuel-injected two-strokes”

  1. Wow, 18 years or so since smokeless direct injected 2 strokes from Bombarier. What an efing joke. Waste of engineering talent and resources

    1. Willy – “Wow, 18 years or so since smokeless direct injected 2 strokes from Bombardier (fixed that for ya). What an efing joke. Waste of engineering talent and resources.”

      Not quite. Outboards, snowmobiles and personal watercraft don’t have the same space limitations as a motorcycle. KTM has done an admirable job in that respect.

  2. Is there such thing as smokeless 2 stroke oil? I imagine fuel injection will reduce smoke but can it really be reduced to 4 stroke levels? I’d love a modern RD/RZ 2 stroke. I’d love a 30 year old one, but can’t get past the environmental implications.

    1. ChairmanMaose,

      It’s very likely the total environmental impact (resource depletion + pollution + global warming + acid rain) of building, shipping and using a new “clean” motorcycle isn’t necessarily very different from the impact of buying a good used RD/RZ350, maintaining it properly and running it until it wears out.

      It’s a tricky comparison, as manufacturing has different impacts than running a bike, but some research shows the choice is *not* completely clear for the environmentally conscious.

      I would find a good RD/RZ350 and enjoy the ringadingding with a clear conscience! 🙂

      1. Great post and great points. But you would take in consideration being accosted by an environmentalist with those pillows of blue smoke. I’m on Vancouver island. I’m certainly considering it. There’s one close to my home with a collector plate for sale. I gush at the photo. Cheers.

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