Ill start this one off with a little story.
One day, at the spare parts counter, was a man trying to buy a clutch lever for his Guzzi V50 or similar (I forget, not important). Steve, our Guzzi expert, was telling the man how he could buy a Pantah one and have it simply modified to suit. The man was having trouble with this, prompting him to say, "I just dont understand how its going to work". This seemed to provoke the smart arse in Steve (never hard to do), who replied "Mate, I dont understand how the TV works, but every night I go home and the news is on".
The implication being, it doesnt matter if you understand how it works, you can use it anyway just fine. And this is about the best way I can start a discussion on electronic fuel injection.
I was going to outline all the different systems, history and give diagrams, etc, on how it all works, but really didnt see the point. If you want to know all that, there are plenty of thick books on the subject. Im not going to write that much. The information given relates to the Weber Marelli systems, covering all ECUs - P7, P8, , , and Bosch Motronic , and . The F650 BMS system will be much the same also. What follows is how the digital electronics go about making it all happen.
So, lets start with a "map" to see whats there. The map contains the info the control software uses to tell the injectors how long to open for, and the ignition circuit when to fire the spark plugs. The ECU itself is just a little, specialised control system computer, totally unaware that it is making a motorcycle go vroom vroom. The map is different for each bike model capacity, state of tune, etc, whereas the same ECU can be used, with the appropriate map, in any bike (or car, truck, boat, etc) designed to work with it.
The following is the "map" information, as printed out by Duane Mitchell of Ultimap, incorporating Fuel Injected Motorcycles. This is how his software displays the map info in an easy to read form, and the map in question is from a Cagiva Gran Canyon. This is a Ducati 900 cc engine, of the Monster "small valve" variety, fitted with the same injection hardware as the 900 SS/Mie, but being run by a Weber Marelli ECU (the rectangular one with the rubber plug on top). The Ducati 900 SS/Mie used the smaller ECU.
Methanol is a toxic and highly flammable chemical. 100% Methanol ignites easily and burns vigorously with an almost undetectable flame. Methanol can be absorbed through the skin and even small amounts can cause blindness or even death. Using this fluid at high pressures, without dilution, in an under-hood environment with nylon lines and push-to-connect fittings is very unsafe. The performance advantages of using greater than 50% methanol concentrations are small, if they exist at all. However, the safety issues are very real and far outweigh any perceived benefit of running high concentrations of methanol.