Fuel injection on a 650R?

OK, This may be a stupid idea... but I can't help liking the theory and possible practicality of it..

Anyone have any thoughts on HOW to add EFI to the Pig motor? My motor is in a quad chassis, custom built etc etc, and I started with the Edelbrock as it was part of hte engine deal. After trying to make that work, and giving up and going with a 43mm FCR it is a lot better but now its a total fuel pig compared to the Edelbrock. the other issue I have is with starting the beast - with the frame design I had to go with E-start only so no kick backup. I notice no starting differences with the FCR compared to the Edelbrick, but if I have a tough time getting it to fire right off its pull start time. Yes, Even with a huge battery from another 650cc class motor.

For those of you wanting to tell me how great the E-brock is I know its a good carb, but the replace it or rebuild it every year is a huge pain. The biggest DANGER I have with it has been real long hill climbs, and the design of the float bowl needle it won't flow enough, or sometimes ANY fuel and it dies half way up a huge climb. On a bike, yeah, just lay it over, a quad (and no bashing either ya hosers!:thumbsup: ) makes it a WHOLE lot more dangerous to change course with a dead motor... So no, the E-blaock is no longer an option for me...

So, back to EFI, thoughts on what to use, how to do it etc?


Check out hondas new 700 fuel injected quad. I have been told the motor is based on the 650r and they added the FI. I saw one two weeks ago at a bike show in California.

The Edelbrock gave you alot of trouble eh? Weird! Mine seems to work very well up some very steep & long climbs and I've never had any issues out of it. But FI would be a blast specially if you can tune it!

hope u got the green for that endeavor

I could tally up a list of estimated costs for fuel injecting with a MegaSquirt, but there are so many variable that it wouldn't be terribly accurate. My personal setup on a Briggs flathead ran up around $600-700, but that included a wideband oxygen sensor and a turbocharger.

The "how" part of EFI isn't really that complicated, but I suspect you have a lot of carb tuning to learn before you condemn either the Edelbrock or FCR. Either you haven't sorted out the current carb or there is another underlying problem.

Check out DIYautotune.com and look specifically at the Microsquirt. It is a product designed for exactly what you are trying to accomplish:ride:

This is from their website:

MicroSquirt Engine Management System [MicroSquirt] $400.00

MicroSquirt is a fully-assembled surface mount (SMT) version of the MegaSquirt fuel injection controller and is most like the MegaSquirt-II and V3 main board assemblies. The intended use is aimed at motorcycles, snowmobiles, personal watercraft, and other similar applications. Wiring harness is included (approx. 3').

MicroSquirt is basically the same as the MegaSquirt-II/ V3 main board, with the main difference in the injector drivers, MAP sensor which is external to the case, and connectors (the VR circuit is also different).

The fuel injector drives will max out at 5 amps each, enough to drive one low-impedance (or 4 high-impedance) injector per bank. To get everything to fit without lots of heat sinking, MicroSquirt uses the ST VND5N07 from STMicroelectronics to drive the injectors. This is not a 'peak and hold' driver, but it does clamp the current at 5 amps, so it can be used with one low-impedance injector per bank, however the close time may be a tad higher (or you can use resistors). For up to 4 high-impedance injectors per bank, it should work fine. For example, for motorcycle use MicroSquirt will be perfect!

In order to shrink the 'footprint' of MicroSquirt, the MAP sensor was left off the board. An external MAP sensor, such as those from General Motors products, can be used instead. See the MicroSquirt hardware page for more information on MAP sensors.

We carry and recommend either the GM 3 bar MAP sensor for an easy weather-tight solution, or you can also you an 2.5 bar MPX4250AP which is the standard MegaSquirt MAP sensor, it's designed for PCB mount, but you can get creative if you'd like.

The board will also use the 35-pin AMPSEAL connector and a sealed case to make a fully sealed unit. Amazingly, the board is the physical size of a business card - connector and all. MicroSquirt's board size, including the 35-pin AMPSEAL connector, is very small - 2.4" x 3.5" (61mm x 89mm), just slightly bigger than a credit card. The case measures:

Length (end plate to end plate, not including flange): 2.75" (70 mm)

Length (end plate to end plate, including flanges): 3.75" (95 mm)

Width: 3.73" (95 mm)

Height: 1.70" (43 mm)

MicroSquirt also has dual channel ignition drivers as well as both the Variable Reluctor (VR) and optoisolated 'Hall/optical/points' tach inputs.

The bootloader is externally accessible, so there's no need to open the case, even to load new code. And the serial RS-232 signals come out of the AMPSEAL connector (instead of a DB-9 on the front, as with MegaSquirt). The board is sealed in a weather proof enclosure.

I can help you with your fuel injection install.

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