EFI conversion on a Gen-1

Yamaha Star V-Max VMAX Motorcycle Discussion Forum

Help Support VMAX Forum:

DreamV4

Well-Known Member
Joined
Jun 30, 2021
Messages
574
Reaction score
144
The Speeduino could handle 2 O2 controllers in code but i`m not sure if the signals could be combined. With a four-in-line with one manifold is much easier to install the O2 sensor.

I could run 1 O2 off of the rear right cylinder and run 1 in the exhaust to see if there isn't a large deviation between that one cylinder and all four. But let`s not get carried away :D
you can weld O2 sensor bung on each pipe and install plugs until you decide to check each cylinder.
 

RempageR1

Well-Known Member
Joined
Mar 16, 2009
Messages
271
Reaction score
92
Location
Netherlands
Yes, I`ll likely keep the one in the mufflers and add one or 2 on the rear downpipes. The front ones are dual walled so that`s a lot harder to weld a bung to.

Since the trigger signal still wasn't perfect, I added a second pick-up. I suspected that the RPM spikes and losing sync was caused by both the ignition system and speeduino sharing the same pick-up. So the new type pick-up you see on the right is used for the Ignitech ignition and the left one is used for the Speeduino. As you can see, the left unit has two pick-ups in one, only the top one is used there.

30.JPG

But again, no luck! Still seeing spikes. So I needed to validate the Speeduino hardware and especially the VR-conditioner. The pick-up coils are of the variable reluctance type which sends a small electronic signal in case it detects a ferrous object. More on it here:


So I needed something resembling the flywheel and with edges that count as lobes. After some thinking, this is what I built :)


So that`s a saw blade powered by a small electronic motor (which was part of the throttle bodies` fly by wire system). And with that, I was able to conclude the electronic components are fine.


So the next theory is the signal gets interference from the magnetic field generated by the flywheel`s magnets and the alternator coils. I will test some shunt resistors to reduce the signal. To be continued :)
 
Last edited:

02GF74

Well-Known Member
Joined
Mar 26, 2020
Messages
1,082
Reaction score
503
Location
UK
Do you have a screenshot of the spikes and the signal from the sensor?

Do the spikes occur randomly?
 
Top