ChinaRiders Forums - View Single Post - ABS on the RX4 .... use both brakes or else !

Bob Kelly · 05-20-2022, 03:30 AM

To me that statement says the sending unit for the ignition is mounted in such a way that it cannot be changed.... the CPU does all the dirty work of spark advance or retarding
so the sending unit just sends a signal to the cpu at a certain crank position....
this is all well and good because the cpu calculates what the exact timing should be
.... so the only way to change that would be to move the unmovable sending unit a tiny amount....so it would send it's signal a little bit sooner or later to the CPU the CPU will still preform the same calculations on the signal and fire the sparkplug at a slightly different time, the end results would be a change in the ignition timing....
Yes it's probably easier by far to just re flash the CPU but not all people know how to do that or have the equipment to preform such a task.... so they might like me consider the task of moving the sending unit a tiny amount ! mechanical changes to me are far easier for me to understand than soft ware programs that you have to learn and need to know really good before you make changes to the program inside your CPU
i.e. it's easier for me to drill and tap a hole for repositioning a sending unit than to spend 6 months trying to gather the e-prom burner and software needed and all that !
..... the problem is it's not the timing that is the major problem with the RX4 it's the fuel
they told the CPU to be way too lean so they would get past the EPA standards ...
.... something as simple as replacing the injector nozzle with a slightly bigger one may be all that is needed without touching the programming of the CPU !!!!
but where to get one is completely unknown at this time ! but to me that has great merit.... because the CPU controlling the injector turns the injector on and off at a certain duration each time and that of course varies with engine RPM....
the fuel pressure is a constant pressure ( if the fuel filter is clean) (if it's restricted it would run leaner than normal...like your bike eh ?) but... if we swapped out the injector for a slightly bigger one it would be like changing the main jet on a carbureted bike...
nothing else would change... because of the size difference more fuel would be added each pulse... and no more lean ... at least that is the idea...
....
Bob.......

05-20-2022, 03:30 AM	#36
Bob Kelly Join Date: Jan 2022 Location: Weed, California. Posts: 271	To me that statement says the sending unit for the ignition is mounted in such a way that it cannot be changed.... the CPU does all the dirty work of spark advance or retarding so the sending unit just sends a signal to the cpu at a certain crank position.... this is all well and good because the cpu calculates what the exact timing should be .... so the only way to change that would be to move the unmovable sending unit a tiny amount....so it would send it's signal a little bit sooner or later to the CPU the CPU will still preform the same calculations on the signal and fire the sparkplug at a slightly different time, the end results would be a change in the ignition timing.... Yes it's probably easier by far to just re flash the CPU but not all people know how to do that or have the equipment to preform such a task.... so they might like me consider the task of moving the sending unit a tiny amount ! mechanical changes to me are far easier for me to understand than soft ware programs that you have to learn and need to know really good before you make changes to the program inside your CPU i.e. it's easier for me to drill and tap a hole for repositioning a sending unit than to spend 6 months trying to gather the e-prom burner and software needed and all that ! ..... the problem is it's not the timing that is the major problem with the RX4 it's the fuel they told the CPU to be way too lean so they would get past the EPA standards ... .... something as simple as replacing the injector nozzle with a slightly bigger one may be all that is needed without touching the programming of the CPU !!!! but where to get one is completely unknown at this time ! but to me that has great merit.... because the CPU controlling the injector turns the injector on and off at a certain duration each time and that of course varies with engine RPM.... the fuel pressure is a constant pressure ( if the fuel filter is clean) (if it's restricted it would run leaner than normal...like your bike eh ?) but... if we swapped out the injector for a slightly bigger one it would be like changing the main jet on a carbureted bike... nothing else would change... because of the size difference more fuel would be added each pulse... and no more lean ... at least that is the idea... .... Bob....... __________________ It's too late when you've gone too far !
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