My motor doesn't have these wires coming out, but the motor I got off another f2 does. What is it for and where can I wore it into my harness? Left side of picture is sprocket location

 

I think, but this is only a thinking, that it is the neutral sensor, if so it turns the light on on the dash.

My f3 engine has this and my f2 Dosent, are you 100% sure it isn't an f3.

 

No I'm not 100% I just know it came out of an f2 frame. The rest if the wires are different to varying degrees but similar enough that I figured them out. Any ideal on how to wire that up?

 

I'm betting that's an f3 motor. What's the engine code on the block - You can determine where the motor came from.

That's the speed sensor on a F3 motor according to the F3 manual's wiring schematic - Green, Pink, Black wires.

Might make for some interesting interaction with your f2 airbox if that motor still has F3 carbs.

To wire that up - you'd need an F3 gauge cluster.

 

So speed sensor is how important of I leave it unhooked?

 

If you're installing this in an F2, and you have the speedo gear drive on the front wheel, than you don't need this sensor, also, if you're installing it in an F3, which has an aftermarket speedo using a sensor and magnets at the front wheel, then you don't need this sensor.