Direct Injection - for and against

[Chris2T]

I previously believed the only way 2 strokes were going to see a rebirth (since legislation won't help us) was through direct injection. This is not to say that the rules in motocross couldn't be changed to allow existing carb'd bikes equal displacement and therefore a rebirth that way, but as far as 2 strokes becoming mainstream again, i thought it had to be via direct injection. But after watching the Rotax E-Tec videos over and over  http://www.ski-doo.com/brphtml/skidooenginetech/en/Index.htm it occured to me that this kind of technology - which would be unbelievably awesome and revolutionary for a streetbike - is exactly what we DON'T need for the dirt. Everyone complains about the high entry fee and nightmare rebuilds of 4 stroke mx racing. Well the E-Tec is LOADED with technology and expensive bits - an ECM that is cooled by fuel, high tech fuel pump, complex injectors, complex oil pump, intricate exhaust valve. Bits tend to fail no matter how well built they are. I'd like to keep it simple and inexpensive. Perhaps use the lower tech Semi-direct injection or Ficht systems - greener than carbs and very frugal with fuel. We aren't talking about bikes that need to pass emission standards anyways.   
The one added expense i'd like to see become standard on all 2 stroke mx bikes regardless of fuel delivery is Oil Injection. A well designed system would add maybe a pound or so, and since it would borrow from existing technology, wouldn't add much to the cost of the bike. But it would eliminate yet another reason why people should go 4 stroke (yes i know about frequent oil changes on mx 4 strokes). And less people buying 4 stoke is how we get our beloved 2 stroke back.
Thoughts?

[ford832]

I don't like oil injection.It's good but if it fails-and it's not uncommon,the results are catastrophic,and usually come with little warning.As for DI,as stated elsewhere,I love FI but on a dirt bike I think it adds too much weight and unnecessary complication.Regardless,the likely question for the future of the 2t in these perceived epa friendly  days is -Do you want a DI 2t or none at all.I'm betting that's how it will go.

On a side note,oil injection is available for most KTM models from the factory as in some markets they are sold this way.The fiche that came with both my KTM's had the part $'s listed in it.

[JETZcorp]

The line, "we aren't talking about bikes that need to pass emission standards" scares me a bit.  Personally, I've never ridden on a motocross track and don't intend to make a habit of it, but I do ride in the forest using MX bikes.  A lot of people do.  While it may seem silly to make a racing bike keep up with emission needs because it doesn't apply to the tracks it's designed for, I think the non-track-riders represent a fairly large part of the market.  I'm not sure if there are emission standards for forest riding, but I've heard that in California, you're not even allowed to take an MX bike on trails or into the woods.  It's either got to be turned off, or on a track.  Why is that?  It might be a concern for safety, because MX bikes tend to be fast, but I think it's a push to get the evil, baby-seal-killing two-stroke motocrossers off the trails and replaced with nice fluffy XR250s and such.  Besides, even when you take the law out of it, I think that making a bike that's AT LEAST comparable to a 4T in emissions is the right thing to do.  If we can do it in a simple package (ex nay on the injection) whilst increasing performance, so much the better.

I'm not trying to imply that you're against clean bikes or that we need to abandon performance in the name of pleasing the hippies, but I just want to point out that our beloved two-strokes have done some pretty serious damage to Southeast Asia, and a lot of that pollution gets blown 'round the world.  We don't want to be making any more of that if we don't have to, especially when there are governing bodies that have shown a history of out-right banning things that hurt environmental quality.  Direct Injection has been shown to improve the two-stroke in this category dramatically, as I'm sure you guys already know.  That makes it an option for the future, but not the only one.

Just thought I'd throw that out there.

[2smoker]

I want a cleaner, better 2 stroke bike and it only can be achieved by direct injection just like the ski-doo and envirude engines! As far as I know OSSA did it on 2 wheels without compromising the performance and adding weight. Getting a custom map done for the injection system is not that expensive also. Everybody has a frigging laptop...

This baby rocks!!!

Onthulling Ossa TR 280i Trialmotor 01 www.nieuwsmotor.nl

[JETZcorp]

I think the Ossa injects into the crankcase, doesn't it?  Besides, I think there's been some talk about some special carb (3-circuit, was it?) that can match the emissions performance of injection without need for a laptop.  Because seriously, if something on a carb goes wrong, you can tear it apart and fix it.  If some little electrical thing gets fried in the injector, chances are you're gonna be SOL until you can wheel your bike up to someone with a few phD's in circuitry and computers, by which time your weekend will have long ago been ruined.  And that's assuming it goes wrong in camp.  What if it goes wrong out past the Devil's Tee (the magical intersection at which a bike always breaks down) and you're 20 miles from the truck?  With a carb you might have a chance at getting it fixed, but with an injector I suspect (though I'm not 100%) that it would be a bit more difficult.

[2smoker]

The new OSSA website is up and running! http://www.ossafactory.es/intro.html

[metal_miracle]

I see electronic fail.
and we even have some of those components on a mx bikes to day

i have seen oil pumps fail but actually very few, and those are very light too
but the minus would be the 2stroke oil  not the plastic tank since they are now weight at all.

the good thing would be you  dont need to jet the bike  
and if the bike is anything like the ktm 85  
you dont need to split the bike almost in half to test idle jets



 

[Out of Order]

I'm for DI, but in MX which is closed course racing it isn't really necessary. Why? Because the EPA can't regulate it unless they want to kill racing altogether. That's my take on it. For other applications, such as on road, DI would be a necessity because of pollution control. Isn't this like the tenth time I have said that.

Not trying to bust any ones stones, but this has been talked about a few times in the technical section. Read it up. Finally electronics have come a long way since the vacuum tubed Bendix days(1950's), so electronics being unreliable is crock of you know what. Don't forget every modern bike has electronics, which is the ignition module. Has yours craped out recently? Not mine.    

[Hondacrrider]

I'm for DI, but in MX which is closed course racing it isn't really necessary. Why? Because the EPA can't regulate it unless they want to kill racing altogether. That's my take on it. For other applications, such as on road, DI would be a necessity because of pollution control. Isn't this like the tenth time I have said that.

Not trying to bust any ones stones, but this has been talked about a few times in the technical section. Read it up. Finally electronics have come a long way since the vacuum tubed Bendix days(1950's), so electronics being unreliable is crock of you know what. Don't forget every modern bike has electronics, which is the ignition module. Has yours craped out recently? Not mine.    

I guess we can wait and see when the fi systems on the yamaha's, Suzuki's, Honda's, and kawasaki's break down, but, I don't think they will, just look at car fi.

[Out of Order]

The car electronics have come along way to hold the 100,000 mile federal warranty. So I really don't think they will fail, maybe some will because of defective parts. I have seen some weird stuff with car electronics though, thanks to all the emissions and integrated crap, such as immobilizers, and trans control built in to a ecu. I don't blame the people who fear electronics, they do some what complicate things. For example my car wouldn't start on day, I checked every thing. For some odd reason I could swear it was the clutch switch (even after pulling it out and checking resistance). I disconnected the connector and jumped the two wires, voila my car fires right up on the first try. I read the Alldata and guess what, it was wrong.

The car drove fine until the ball joint snapped. But that just goes to tell you if a switch fails it can take some time to figure out the problem. Then again electronics can complicate things and that's why people don't like it. For me I like the challenge. Maybe I should FI a two stroke for shits and giggles.    

[JohnN]

Not to complicate things but I have a few random thoughts to add....

There are two systems being bandied about FI and DI... probably could retro-fit a current MX bike to FI in your garage (if it's a very well stocked garage and your an engineer) but a DI bike would be much more difficult for even a very sophisticated engineer/machinist to integrate into an MX bike.

The two-strokes being used in southeast Asia are mostly powered by KE125 two-stroke motors.... which is older technology and highly polluting. My guess is that they would pollute less with new style engines, but it would be more expensive. So there is a retro-fit program to add DI to these machines and it's making a difference.

While I'm not sure of the exact figure, what I recall is that 70% of motocross bikes sold do NOT ever see a motocross track! They are used for play bikes, trail bikes, desert bikes, etc, etc.... While closed course racing (Motocross) does not have any emissions, this doesn't show the complete story. The EPA and Euro standards are taking this into consideration and the responsibility falls to the manufacturers to ensure that these machines meet the standards set.

Obviously this is a law with lots of loop holes created by our friends in D.C. and those with close ties to them receive relaxed standards... just the way of the world...

The DI systems hold the most promise for lowering emissions on two-strokes and is the reason this question comes up so often. But the question remains is it something that would work well for motocross racing applications.... a big un-known at this point.

[meger z]

dont forget this http://www.motorcycle.com/manufacturer/honda/honda-exp2-14293.html

[2smoker]

The technology is there but the manufacturers want to build and sell 4 strokes. Nothing to do with EPA, just ca$h. It is a business and Japaneses are hungry. If you want 2 stroke back, we have to stop buying the damn junk. and feeding them.

[metal_miracle]

aprillia have had it on theire  scooters for a few years now

http://www.aprilia.com/en-US/Model/74/SR+50+R+FACTORY/Technical.aspx]
[url]http://www.aprilia.com/en-US/Model/74/SR+50+R+FACTORY/Technical.aspx[/url]

[Recovered]

I'll give a few of my repetitive thoughts.

1. Most guys don't tune their bikes correctly. This includes all those who THINK they have it right, but they don't.

2. EFI and DI won't fix stupid. Stupid SHOULD hurt. I have been around long enough to see tune ups so screwed up it's not funny. And you can't help these guys. It's the way they have been doing "it" for years, and their stuff doesn't "blow up", even though I have not killed any parts in forever.

3. Pay close attention here, because Mad Scientist is going to go prophetic on you. IF you get EFI or DI you WILL get  testing, catalytic converters and all the same crap you have on your car. I KNOW that the government was testing 2T emissions in the late 60's and early 70's. They could get the bikes clean enough, but the oils (and other factors go in here) were not god enough to lube at those lean ratios. Now you know why Mad Scientist bitches constantly about tune up and using JUNK oil (I'll say it here, 927 Castor is one of those that falls into this category). You guys make it 1000 times harder on those in the trenches to fix the PERCIEVED problem of 2T's, that being emissions. That is a huge part of the problem. And guys have their bikes smoking all the time, spooge running out the pipe like Niagara Falls and people SEE this. These morons THINK it is a problem.

It is on YOU, those who think any oil is good, that 2 "smoker" is a good saying and you use it all the time, you guys whose bikes smoke like Cheech and Chong on a blow out party day, you whose spooge covers my bike, my goggles and leaves a rainbow of colors in EVERY SINGLE mud puddle you go through...you guys need to learn about oils and tune up. A 3 circuit carb, good oil and a RACE tune up (even for MX bikes in the woods, that's all I've ever rode in the woods...MX bikes) will do MUCH to help in the battle to keep 2T's around. WE are as much the problem as AMA and Japan. GET WITH IT.