F4i Crank and Cam sensors

[Peter Andruskiewicz]

I'm part of a new FSAE team, and just started playing with the spark timing for our 2001 CBR 600 F4i engine. I have been able to find out online that the speed/crank sensor is a 12 tooth hall sensor (3 wire) while the cam sensor is a 3 tooth VR sensor (2 wire). The confusion is whether the 12 tooth is 12 evenly spaced teeth, or a 12-1 or 12-2 wheel, and whether the 3 tooth wheel is a 4-1 or evenly spaced 3 tooth wheel.

I am trying to integrate the stock sensors into a Megasquirt V3 board running MSnS-E on an MS1 chip. Has anyone tried anything similar to this and have any tips?

[Peter Andruskiewicz]

I'm part of a new FSAE team, and just started playing with the spark timing for our 2001 CBR 600 F4i engine. I have been able to find out online that the speed/crank sensor is a 12 tooth hall sensor (3 wire) while the cam sensor is a 3 tooth VR sensor (2 wire). The confusion is whether the 12 tooth is 12 evenly spaced teeth, or a 12-1 or 12-2 wheel, and whether the 3 tooth wheel is a 4-1 or evenly spaced 3 tooth wheel.

I am trying to integrate the stock sensors into a Megasquirt V3 board running MSnS-E on an MS1 chip. Has anyone tried anything similar to this and have any tips?

[Poe]

Both the crank sensor and cam sensor are variable reluctance. The crank has 12 evenly spaced teeth while the cam trigger wheel is 3 teeth with weird spacing. I think it is pretty common to just grind off two of the three teeth on the cam trigger wheel. Have you not opened up the case or popped off the valve cover yet?

[Peter Andruskiewicz]

No, we havent opened up the motor yet, but it sounds like we will be, with the dremel nearby. If the speed sensor is a VR, what's the third wire on it for? Thanks!

[Poe]

I'm not sure what you have, but all the F4i's we've ever bought use a two wire crank and cam pickup. The crank pickup is the two wires coming out of the top of the clutch cover, on the right side of the engine. There is a three wire speed sensor that normally goes to the speedometer on the bike. Maybe that is what you are seeing? Pink, black and green wire?

[Peter Andruskiewicz]

ah, you nailed it, i was looking at the speed sensor. We havent disassembled the engine yet, so I dont know it in too much depth. Thanks

[Peter Andruskiewicz]

One more question... does the stock F4i motor trigger off of the rising or falling edge of the VR signal?

[Analogue]

It doesn't really matter-- just switch the wires. Neither is grounded internally.

VR sensors will have a zero crossing in the center of a peak or valley. I believe I treated the wire with the white stripe as the ground, and the solid color (yellow?) as the signal. If wired like this, the ECU should trigger off of the negative going zero crossing, which seems to be a common setup.

Keith