Help with building your Speeduino, installing it, getting it to run etc.
By LAV1000
Dmitry and JHolland.
You guys mention the MAX9924.
I thought the VR conditioner uses the MAX9926 :?

Using scope, like JHolland said:
You need change the voltage range so you can see the amplitude properly
Mess around whit settings until you get a nice picture on the screen.
I post a picture of one of mine scope screens, it is a dual channel but focus on the green channel.

What is the value of your tuning potentiometer ?

I now you like the bike be sequential on its fuel settings.
But it might be better to focus on the crank sensor only and if it works right change to sequential.
I still think your bike could be running on whit an vr sensor.
Do you use a screened cable to the speeduino ?
And where did you connect the screen ?
VRvsREV outpOEM2.jpg
VRvsREV outpOEM2.jpg (130.03 KiB) Viewed 198 times
By Dmitriy
The MAX9926 chip is soldered to the VR board. Judging by the datasheet MAX9924-MAX9927 differences in the number of channels.
10kΩ tuning resistor
My oscilloscope has a total of one channel.
I shot a video of the oscilloscope screen.
At the beginning of the video, the “+” wire of the oscilloscope is connected to output No. 8 of the VR board.
Then he switched the "+" wire of the oscilloscope to the input signal from the VR sensor (connected to pin JP4 immediately after the 1kOm resistor)You can see how the signal is changing.
Then I re-connected the wire to pin 8 of the VR board and rotated the resistor.
The "-" wire of the oscilloscope was not involved.
It seems to me that the output signal from pin 8 of the VR board should be of a different shape.
The wire from the VR sensor is unshielded, such as it was from the factory.
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By Eric H
It looks like your scope is on an AC coupled input. For looking a square waves you really want a DC coupled input.
You need to hook up the - input of the scope to a good ground, preferably the ground at the VR conditioner for the cleanest signals.
By Dmitriy
Guys it seems the VR board has earned !!!! :D :D :D :D
How I did it: I installed the jumper JP4, I removed the resistor R10 from the VR board.
On advice, the LAV1000 turned off the camshaft sensor and used the Semi-Sequential mode.
The motor spins perfectly in all speed ranges.
There are a few minor issues:
1 after the gas discharge, it is flooded, but I think after setting up the VE card this problem will disappear.
2 does not start as with standard ignition, it takes more time to turn the motor with a starter and slightly open the throttle.
I noticed an error in the engine speed readings, I register the file, then I look at the log, for example, the maximum speed was 12300 in the log, but I remember that the motorcycle tachometer showed 14500 -15500. I don’t know who is wrong, the motorcycle tachometer shows more or speeduino writes less to the log file, but I notice this every time I write a log file with maximum engine speed and maximum speed on the road. And each time in the log file the engine speed is 2000-3000 less than it was on the tachometer.
I will try the option using a camshaft sensor and sequential injection.
If everything bubbet works fine, I plan to put a second row of nozzles above the throttles.
By Dmitriy
LAV1000 wrote:
Sat Jun 27, 2020 5:22 pm
No sync losses anymore ?
Today I set everything up for sequential injection with a camshaft sensor. It works like a clock !!!
That is, the synchronization problem was in jumper JP4 and resistor R10 on the VR board.
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