Other Direct Injected Two Strokes

I recently read an article in popular mechanics (or was it popular science...) about the production of direct injection two stroke dirt bikes that will hit the market fairly soon. My question to you guys is whether or not you think these engines will translate over to the stand up world and allow for mass production of these by yamaha and kawasaki again. I'm not knowledgeable about engines, so forgive my ignorance with this next question, but would it be possible for someone to create a conversion kit for carbeurated two stroke engines if the two stroke ban does take off and start affecting all of us?
 
for it to be direct injected it would have to inject your fuel directly into the cylinder....via the top of the head(most common)...i think i read an article about seadoo doing something like that...they are injecting the fuel in after the exhaust port is closed.....the article said no smoke and the fuel economy of a 4 stroke....sounds very interesting....
 

JT_Freeride

John Tetenes @Jtetenes
Location
Long Island
correct me if im wrong but i believe seadoo has had a direct injected motor for a while it was a 951 and i know that yamaha had the 06-08 gpr1300r it was also direct injected
 
its very possible....i cant remember what engine brand i read about in the magazine but for some reason seadoo comes to mind....but then again i could be crazy...
 
so could the head potentially just be replaced with one that allows the direct injection + whatever added parts are needed as an alternative to replacing the whole engine?
 
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Location
dfw
so could the head potentially just be replaced with one that allows the direct injection + whatever added parts are needed as an alternative to replacing the whole engine?

That is all that a direct injected twostroke is. They would be useable in a production standup, but there are more reasons why it wont be used and why no more production standups will be made. Remember that Kawasaki, Yamaha, and every other large corporation exist to make money and nothing else.
 

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
Seadoo had two injected 2-strokes in the past. The first (817 RFI) was not a direct inject.
The 951DI motor was direct injected. It also had a crank driven air compressor to inject air into the combustion chamber. That motor was a nightmare to work on. A high pressure fuel system (110 psi operating pressure), lots difficult fuel hose connections, a very expensive in-tank fuel pump that failed often, and a computerized engine that could not be maintained by anyone other than a BRP dealer.
Kawasaki also did fuel injection for a while, in the Ultra 130 DI. It used a third party vendor for the system (FICHT). I don't know much about that one.
It may be possible for a standup, but it's more than just bolting on a different head. I really doubt that Yamaha would bother for the couple hundred units they sell per year here in the US.
 
Aren't the Seadoo 951 DI motors direct injection through the head?

I dont see main stream production jetski motors moving back towards 2 stroke technology despite how much we enjoy it...
 

Vumad

Super Hero, with a cape!
Location
St. Pete, FL
so could the head potentially just be replaced with one that allows the direct injection + whatever added parts are needed as an alternative to replacing the whole engine?

Not for those kinds of emissions. The direct injected snowmobiles also have oil injection. They don't just drop oil into the carb throat like jet skis. They specifically direct oil to the areas that need oil.

I'm sure someone could develop something for our motors if they really wanted to, but no it would not be the same.
 

Proformance1

Liquid Insanity
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Vendor Account
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New York Crew
dont forget about the Polaris Virage I that was a DI 777 that would bolt right into a stand up. Still cant believe not one has done it. Bosch FI into head. low HP 110 and a dog off the bottom end but crack the code, reprogram it, etc, same motor as the old EME 1000 motor.
 

jeremy chambon

Need more power
Location
rockford MI
This may have already been said but the oil being burned In a two stroke is the problem and I read some place about the whole two stroke law something about cal being a hippy state and no two stroke product can be manufactured there. But doesn't mean some a/m complain can't make a crank and a head swap kit that will work. What ever happen to the pjs fuel injection system?
 

Matt_E

steals hub caps from cars
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at peace
PJS injection was a mechanical, gear-driven system. Injection amount is not load dependent. Junk for anything but racing.
 

Schmidty721

someone turf my rails
Location
WI
Tuning a high performance "pipey" two stroke like we run in the skis for DI is very difficult.
It's not something that would be easily adaptable for multiple applications.
 
Location
SoCal
To clarify seadoo had the 951 direct orbital injection,kawasaki had the 1100 triple direct injection, and yamaha had the 1300r efi.

kawasaki and yamaha was much more reliable out of the 3 from my experience. I owned all of them. The yamaha is a true electronic fuel injection, not direct injection. Oil consumption in the kawasaki is much different it does not inject the oil upstream on the manifold side. Rather the oil is computer mapped and injected directly in to certain parts of the motor. Thisis why they use so much less oil and the fuel mapping conserves a lot of fuel. The yamaha still uses a mechanical pump attached to the crank like what we see on the other skis.

out of all the 3 for oil consumption and fuel saving vs power the kawi platform was the best. The seadoo was a headache... The yamaha drinks gas likes its free lol. This is prob cause its a big 1300cc.

i recently just did an 1100 di conversion in my hydrospace standup. I'm getting double ride time on 5 gallons vs normalcarb version and the power is nice very linear.
 
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