FRIDAY WRAP UP: HOW CLEAN IS THE EFI HUSKY 2-STROKE?
HUSQVARNA TE250i INTRODUCTION
Last week I got a chance to ride the fuel-injected Husky TE250i in the mountains around Invermere, British Columbia. This is Husqvarna’s version of the fuel-injected KTM 250XC-W TPI. It was an incredible experience for two reasons. First, the riding up there was incredible. The view was awesome in every direction! Second, I got to learn more about the bike. The most important fact to understand is that this bike isn’t really about the U.S. market. It will only come here in limited numbers. The 300cc version won’t come to the U.S at all (for now). The reason is simple: They need all they can get in Europe. This bike was designed to pass the Euro 4 emission test, which was implemented for all bikes manufactured in 2017. KTM and Husky are all out of bikes produced before that deadline, so dealers are screaming.
The next-most important fact is that the bike hasn’t been shown to pass any U.S. emission tests. The 250i and its twin on the KTM side of the fence are imported as closed-course competition vehicles, just like carbureted two-strokes and unrestricted four-stroke MX bikes. But the engineers say that the new motor is so much more efficient that it’s not out of the question. I’m no engineer, but from what I understand, getting this motor approved in the U.S. is unlikely. The main reason a traditionally carbureted two-stroke is “dirty” is because there’s a brief period in the cycle where the incoming, unburned gasses can escape directly out the exhaust port. Those unburned gasses are what emission testers absolutely hate. In a clean two-stroke like the Rotax E-TEC system, gasoline isn’t injected into the motor until all the ports are closed, just before combustion. The engine compresses clean air, and then, just before the sparkplugs fire, extremely powerful injectors spray fuel into the combustion chamber. Combustion occurs and burned gasses leave the engine when the piston uncovers the exhaust port.
In the illustration above, it appears that the TPI system has the same issue as regular two-strokes. The little arrow shows unburned gasses coming out of the transfer port and there’s nothing to keep them from going right out the exhaust. The reason that this engine tests better than throttle-body injection is because it’s more fuel efficient. Husky engineers say it burns 40 percent less gas.
In Europe, a homologated version is street legal. It has a catalytic converter (visible above), an intake restrictor and a throttle stop. There’s a walk-around video from a European dealership on line.
So why should we care? Because of the jetting issue. Every time we test a modern two-stroke, we spend half of our time trying to get the jetting right. On some bikes, it’s perfect, right out of the box. On others, it’s a nightmare. Mid summer is when most new bikes are released, so we often have to figure out jetting when it’s over 100 degrees in Southern California. By the time those specs get into print, it might be 40 degrees in Michigan, and everything is wrong. That issue should go away now. In Canada, we didn’t have much temperature variation, but we sure had to deal with an increase in altitude. The bike handled it extremely well. Purists will complain that EFI beings an increase in weight, and that the system is locked, so you can’t adjust the jetting (mapping) even if you want to. Maybe so, but the benefits, in my mind, outweigh the drawbacks.
WORCS, 2002
This week’s random harddrive search uncovered the final WORCS race of 2002, in Honey Lake, California. This was the second year of the WORCS program, which was founded by Dave Hamel. Dave’s family was and still is deeply entrenched in off-road racing. His brother Danny had been gone for seven years at that time, but with the help of his father Roger, he built WORCS into the biggest deal in western off-road racing. This particular round was won by Ty Davis, although Mike Kiedrowski used it to wrap up his second consecutive championship. Ty actually won most of the races that year, but had a DNF that put him out of the running.
The race itself was a muddy mess for the pros. The amateur classes went off without a hitch on Saturday, but it rained all night and throughout most of the three-hour pro race. Identifying the riders is always interesting at races like this. In the photo above, the only indication that it’s Kurt Caselli is a little piece of his name on the number plate. He was second at that race.
Rodney Smith was fifth, although he was there mostly because it was close to home. Suzuki’s off-road team invested heavily in the WORCS series under the leadership of Mike Webb. The series stared right after the introduction of the DRZ400, so Suzuki developed a killer four-stroke GP bike that would probably still hold its own today. Rodney, at the time, was focused on racing an RM250 two-stroke in the GNCC series back east where he was on top of that game. The super DRZ was retired the next year. It was a difficult bike to build and production 450 MX bikes were just arriving on the scene.
I personally raced that weekend on what I remember as the best KX500 ever. It belonged to Ty Davis. Ty was still riding for Yamaha at the time, but he had a special affinity for the KX and knew the bike inside out from his earlier years at Team Green. He designed his own pipe and had IMS build a special, slimmer fuel tank. The crank was rebalanced, the frame was reinforced and Ty did the suspension valving himself using Race Tech parts. That bike was incredible. The KX500’s last year was 2004.
HARD ENDURO CORNER
GARY’S THING
I’m trying to get a bike together for the Old School Scrambles at Glen Helen, but it’s a struggle. Gary Jones talked the promoters into adding a class for post vintage bikes, which should make it appeal to a broader group.
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SOUTHWICK!
See you next week,
–Ron
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