Neutral light question

bpcough

Registered
I have built a mini-dragster powered by a hayabusa. I had to completely change the wiring system because i use a motec ecu.
I need to add a neutral light on the dash to make it legal for the drags.
It seems to me that the neutral sensor is on the clutch side of the motor. There is a red, blue and black wire running out of the sensor.
Can anyone tell me how to wire up a neutral light?
thanks
Bryan
 
Man, wish I knew, someone will chime in. Welcome to the oRg. :beerchug: I think that signal comes from the "gear position switch". Still looking. Maybe the black wire, someone confirm?
 
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Welcome to the org.! I'm thinking the GPS to is where it would be.
 
thanks guys. I put 12 volts to the red wire with the motor in neutral and tried
a test light on both the blue and black wire and got no light.
I am a bit puzzled. I wil post some pics as soon as i figure out how to.
Bryan
 
Here is a photo.
I hope it works
Bryan
hayabusa.jpg
 
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B/W is negative, P to P on the ECU, Bl to Bl on ECU wiring diagrams 8-14 and 8-15 online manuals for 99-07.
 
When you release the clutch and it doesn't move...it's likely in neutral :poke:

Umm - Yeah, smithabusa would probably be able to tell you right off.

Take this with FWIW, though. I've never taken the GPS apart, but what I've read...I believe it's more or less a bunch of resistors. The 3 wires that you're referring to on the clutch side are the GPS... I bet one is ground, another is +5V DC and the 3rd is a 'sensor' wire. The ECU is reading the voltage off the sensor wire. Each gear has a specific resistor - 6.8K for 5th, 15K for 6th, etc. By reading the voltage on the sensor, the ECU knows what gear the bike is in. Now, all that said, I don't know what the value is for neutral...this is where smithabusa may be able to help.

My guess is that you would have to build something that will trigger at a certain voltage...

Or here's another thought, get a gear indicator, such as a GI Pro, Acumen, or even one that smithabusa builds... Then you would know all your gears as well as neutral. ;)
 
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