Honda SC35 trigger sync issues

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Gorfest-n
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Joined: Mon May 29, 2023 3:26 pm
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Honda SC35 trigger sync issues

Post by Gorfest-n »

Hi
There is no stable synchronization during cranking - it can hit TDC correctly, it can miss by 90-180 degrees - full random.
If it hits TDC then the engine starts and runs great.

ECU alphax-4chan, Honda motorcycle four-stroke engine.
Crank - 36 tooth VR.
Cam - 1 tooth VR.
Additional capacitors are installed in both VR modules, adjusting the VR sensor threshold does not help.

https://rusefi.com/online/view.php?msq=1477

The 36 tooth trigger is not original, I also have the original 12 tooth trigger - same problems. I have logs for him too if needed.
Attachments
2023-05-29_17.46.03 36-1 100tps.csv
(118.23 KiB) Downloaded 90 times
2023-05-29_17.46.03 36-1 0tps.csv
(76.99 KiB) Downloaded 103 times
2023-05-29_17.46.48 36-1 0tps+100tps.rar
(419.54 KiB) Downloaded 103 times
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AndreyB
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Re: Honda SC35 trigger sync issues

Post by AndreyB »

instant RPM is definitely telling us _something_

I think I can see uneven duration of primary rise counter? Something is not right with hardware outside or inside of ECU :( At the moment we do not log tooth ratios for wheels without a synchronization point like this 36/0 so we are a bit more blind for such special wheels.
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image.png (62.15 KiB) Viewed 6205 times
Attachments
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image.png (61.74 KiB) Viewed 6205 times
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Gorfest-n
Posts: 3
Joined: Mon May 29, 2023 3:26 pm
Github Username: Gorfest-n

Re: Honda SC35 trigger sync issues

Post by Gorfest-n »

Here is a log with a 12-teeth crank and 1-tooth cam wheels.
From a factory, this motor comes with the 12-teeth crankshaft and a 3-teeth camshaft wheels (but it’s not available now).

Does it makes sense to remove 1 tooth from a 36-teeth wheel and turn on/off a camshaft sensor with the 1-tooth wheel?
Attachments
020190404_125744.jpg
020190404_125744.jpg (59.6 KiB) Viewed 6199 times
2023-05-29 12-1 0tps+100tps.rar
12-1 log
(404.39 KiB) Downloaded 99 times
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