Join Date: Dec 2012
Location: York, PA, United States
Originally Posted by FlyingDuck
The L-Jetronic is an analog device. The only fuel "map" is the hardwiring of the circuit.
The only "initialization" it does is enrich the mixture when the starter button is pressed.
Thank you. Had a talk with an old timer. Told me same thing.
The fast idle control IS a throttle lock. It opens the butterfly valves inside the throttle bodies in the same way that the handlebar grip control does. The difference is the fast idle holds them open against the return springs whereas the right grip control does not.
And the only data the ECU gets for the positions of the butterfly valves, the fast idle knob and the right hand throttle control is thru the Throttle Position Switch. The operator has to properly physically set (orient) the controls, the cables and the TPS in order to get the correct fuel/air mixture during operation. The ECU adjusts fuel/air (mostly) by two bits of data, air pressure reading and throttle position switch reading. The ECU doesnt directly "know" anything about throttle grip position, TPS initial orientation or position of butterfly valves. It only knows the TPS has rotated to a particular point. It doesnt know where the TPS began; it doesnt calculate the distance of rotation, only notes the point.
Last edited by 97tiger885; Feb 24th, 2013 at 10:49 am.