XR650L Fuel injection might be possible, and easy...

Megasquirt is the name of the fuel injection I used. It is totaly self programable. Very low cost. Easy to set up. Gives maximum power, and maximum economy. My XR650L is turbocharged, and the Megaquirt works fine with it. If you want it can control spark advance also. I'm not going to say much more because this forum seemed to be very aggressive, and I am a sensitive person to negative comments. Please go to the Megasquirt site. It will answer all your questions. It has been in use for many years. If someone needs installation help, I can assist.

I have to say a turboed 650l is AWESOME! Any chance you have pictures or are close to Olympia it would be great to check out a piece of engineering like that.

Midnight, what kind of throttle bodies did you use, and what kinds can you use. Throttle body size, injector size etc.

Thanks for coming on and posting Captain Midnight! It's true, there are some dudes on here that seem to have what I like to call an unhealthy sense of internet courage. That's why I've tried to steer this thread into talking about nothing but putting EFI on an XR650L, and if the thread dies out so be it, I just don't want it to turn into a completely different topic. Anyway, sounds like you, or at least some good friends have some serious technical expertise in tinkering around with new ideas that most would be wary of, including me.

I don't know enough about EFI or carburetors to even attempt this without having some sort of laid out plan. I also don't have the money to spend on this (at least not at this very moment), but it would be awesome to see exactly how it was done for future reference. I'm sure we'd have a lot more guys trying it and working on ironing out some bugs, such as the previously mentioned fuel starvation. Do you ride off-road? Have you had any problems related to fuel starvation?

Thanks again, there are several guys on here who appreciate your input!!!

Megasquirt is the name of the fuel injection I used. It is totaly self programable. Very low cost. Easy to set up. Gives maximum power, and maximum economy. My XR650L is turbocharged, and the Megaquirt works fine with it. If you want it can control spark advance also. I'm not going to say much more because this forum seemed to be very aggressive, and I am a sensitive person to negative comments.

You have a turbocharged EFI 650L and are worried about negative comments? :cool:

How are you getting a tach signal to the MegaSquirt? With fuel-only it's not a big deal, but I noticed that you're running a GM 7-pin HEI module and COP. Usually a single cylinder engine has very erratic RPM between combustion events and the MS benefits from a 36-1 trigger wheel when doing spark control.

I have essentially the same MS equipment(including a turbo) that you do, but it's not installed on anything. Naturally it has crossed my mind to put it on my XR600. :applause:

Hi guys I will send pictures of our crank trigger and our sensor mount when I get back from lobster fishing on monday. our trigger is on the inside of the flywheel, next to the starter ring gear.

Does it use a Hall sensor or a variable reluctor? Is it a special part that's heat and oil resistant, or something generic?

its a vrs

here is the flywheel.garage.php?do=viewattachment&attachmentid=53403

here is another picture. note missing tooffgarage.php?do=viewattachment&attachmentid=53402

here is our sensor and mount.garage.php?do=viewattachment&attachmentid=53405

Holy crap, thanks!

Your h-beam rod and oil squirter is showing! :cool:

thats nuthin:thumbsup:

thats nuthin:thumbsup:

All I can do is shake my head and wonder what you guys won't share with the public.

Not that I'm begging, but if ya'll need an apprentice.....or ME.....:cool:

pictures say a thousand words.

here is another picture. note missing tooffgarage.php?do=viewattachment&attachmentid=53402

How does a multi-tooth wheel and pickup improve timing over just using the stock pickup?

I take it one of those trigger wheels is the right size?

Damn you Stepho, now i gotta start thinking about that!

Very nice job on that L engine...:cool:

How does a multi-tooth wheel and pickup improve timing over just using the stock pickup?

I alluded to that here:

Usually a single cylinder engine has very erratic RPM between combustion events and the MS benefits from a 36-1 trigger wheel when doing spark control.

The problem is that the actual crank rpm varies quite a bit between revolutions on single cylinder engines. With only one trigger per event, the EFI computer needs several revolutions to figure out what's going on. This causes the timing to jump around a lot. With 36 triggers per revolution instead , the ECU can follow the erratic low-rpm crank speed accurately and maintain accurate ignition timing.

Running with only fuel control isn't a big deal because the ECU only need to know when to fire the injector(s). It doesn't really matter if the fuel sprays when the intake valve is open or not.

I dont know about your last statement HT. I would think if the injector fires during a closed int valve, that fuel/air mix will tend to puddle.

I know it sounds kind of weird, but that's how all the non-sequential injection systems work(MegaSquirt, BigStuff3, FAST, and even high-dollar Motecs without the sequential upgrade and many OEM systems). In a batch-fire system, all the injectors fire at once. If that system is on a multi-cylinder engine, then there will inevitably be cylinders that get fuel when the valve is closed. Bank-to-bank injection alternates between two injector channels. MegaSquirt has two injector channels and can be set up as batch fire or bank-to-bank. It won't have sequential capability until the router board is released, but it's not necessary on a single nor most twin-cylinder engines. Those can be set up as sequential if only two injector channels are needed.

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