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No thanks I like the simplicity of the carb and if taken care of properly the carb shouldn't give any problems for years and years.
 

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Nothing says 'cool bike' like O2 & MAP sensors!
 

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The problem is no Crank Position sensor or Hall effect sensors to tell the ECM when to trigger the injectors.
'You can't use the rebel ignition pulse sine it spark both every revolution. While Wasted Spark works, a "Wasted Injection" would no be a good thing
Even if the injection system's ecm was to switch injectors every other pulse, the possibility of injecting on the wrong cylinder is still high without a CPS and/or Hall effect sensor setting injection time for No1.

The problem is you would need injector timing off the cam shaft to keep it right.
 

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I thought it was too good to be true. I guess I just need to take a mechanic class in carburetor repair and tuning.

I don't know if you guys have seen this kind of thing before but people are experimenting with ultrasonic vaporizers to run engines. maybe someday this will replace carburetors as kind of a middle of the road between carb performance and injection performance. It's kinda neat.

Car running on ultrasonic gasoline mist (3 of 5) - YouTube
 

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When Honda didn't release a '10 Rebel, some of us- I, anyway- thought that the next gen Rebel would be fuel injected to comply with tighter emissions standards. Turned out to be more about market glut, as the latest Reb is the same bike other than available colors.
 

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Yeah I read you guys talking about that. The suzuki TU250X has EFI and it gets better MPG than the rebel. It's all around better than the rebel in my opinion. Exept in looks. And I don't know how the single engine performs compared to the rebels 2 cylinder set up.

This guy has a good review of the suzuki. I don't like that it looks like a cross between a cruiser and a cafe racer.
Suzuki TU250 review - YouTube
 

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The problem is no Crank Position sensor or Hall effect sensors to tell the ECM when to trigger the injectors.
'You can't use the rebel ignition pulse sine it spark both every revolution. While Wasted Spark works, a "Wasted Injection" would no be a good thing
Even if the injection system's ecm was to switch injectors every other pulse, the possibility of injecting on the wrong cylinder is still high without a CPS and/or Hall effect sensor setting injection time for No1.

The problem is you would need injector timing off the cam shaft to keep it right.

Yup...it's a problem....

Fabricate a solution...obviously. :D
 

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Yes, a single TBI type would inject for every revolution and solve the issue.
 

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The problem is no Crank Position sensor or Hall effect sensors to tell the ECM when to trigger the injectors.
'You can't use the rebel ignition pulse sine it spark both every revolution. While Wasted Spark works, a "Wasted Injection" would no be a good thing
Even if the injection system's ecm was to switch injectors every other pulse, the possibility of injecting on the wrong cylinder is still high without a CPS and/or Hall effect sensor setting injection time for No1.

The problem is you would need injector timing off the cam shaft to keep it right.
Every injected vehicle out there runs wasted injection, even ones with sequential injection. You know why?

As the RPM's increase the amount of time the valve is open decreases. The fuel injector's speed to open(.75-1.5ms before complete open reaction) plus the fact fuel atomizes at a fixed rate based on injector size means the injector has to start firing long before the valve is open, continue through the entire intake cycle, then shut down a little after the valve closes for the injector to cool. Then repeat.

If you want to watch it in action here:
ITB Up Close, 2.0 Dodge Neon SOHC, 8800 RPM - YouTube It does have some language at the end, but it shows the wasted injection in action after the RPM increase to the point sequential no longer can keep up(around 2500rpm)

The manufacturers take into account the wall wetting of the fuel injectors, the X-tau evaporation, the fuel overlap, injector duty cycle, injector placement, and about 1,000 other things into account when designing a proper fuel injection design. When it is done right, it is a thing of beauty. More power, more torque, more fuel economy than any carb can keep up with.


As to converting to FI, I would use microsquirt as it already handles batch fire injectors, wasted spark, any 02 sensor, and can be configured to run off any input, hall, v/r, pulse, whatever. It does require 2 temp sensors(intake temp and engine temp) and a vacuum sensor. It is infinitely adjustable. I run Megasquirt on my race car, it is the car version of microsquirt. The only problem I see with conversion is getting a high pressure fuel system for the injectors. Carbs run on gravity feed. A fuel injection system would require at least 40psi at the injector for proper actuation.

http://www.diyautotune.com/catalog/microsquirt-c-35.html


As far as the future of fuel injection, Ford is using it in its ecoboost. Dodge and Fiat in the varioair and BMW and Mercedes in their engines. The new style is direct cylinder injection at 30,000psi+. No more waiting for valves to open etc, nor for lower pressure injectors not misting correctly. It is super fine mist, directly in the cylinder, not in the intake tract somewhere.
 

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As to converting to FI, I would use microsquirt as it already handles batch fire injectors, wasted spark, any 02 sensor, and can be configured to run off any input, hall, v/r, pulse, whatever. It does require 2 temp sensors(intake temp and engine temp) and a vacuum sensor. It is infinitely adjustable. I run Megasquirt on my race car, it is the car version of microsquirt. The only problem I see with conversion is getting a high pressure fuel system for the injectors. Carbs run on gravity feed. A fuel injection system would require at least 40psi at the injector for proper actuation.

MicroSquirt Assembled Engine Management System
I have a 2005 CMX250 that I'd like to convert to fuel injection using my Megasquirt. Are there fuel injection manifolds or kits available that I can use for the CMX250 engine? I know a fuel pump, fuel filter, and O2 sensor will have to be retrofitted.

Thanks
 
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