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Author Topic: Getting a new clutch lever setup. What to do with the clutch switch wires?  (Read 528 times)

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Offline taoster

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What should I do with the 2 wires that connect to the clutch lever? Do I just connect those 2 together to bypass? And what is the purpose of the switch?



Offline DrM

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If your bike is in gear, your engine will not start, unless the clutch lever is pulled in (under normal configuration.)  Those two wires tell the bike's brain if the clutch is pulled in or not so the engine can start.   So you have to test whether that is triggered by an open circuit or by a closed circuit -- try to start your bike both ways.   

Offline taoster

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Would simply unplugging the switch, or twisting them together, cause the bike to run differently?

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Offline DrM

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Would simply unplugging the switch, or twisting them together, cause the bike to run differently?
.  It won't hurt to leave them open or to twist them together.  One way it won't start or run, the other way it will start and run.  You just have to try it to see which it is.

Offline taoster

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UPDATE:

so i unplugged the clutch switch wires and went for a ride for a couple minutes.. it "sounded" different.. performance wise, i couldn't tell.

Then I connected the 2 wires together, and it "sounded" like what i'm used the bike sounding like.. so.. i guess i will run it like this until something happens.

Is this a "placebo" effect in my head or maybe there really is a difference when simlpy unplugging the clutch switch wires compared to connect the 2 wires together..

Any additional input would be grateful.  Thanks.

Offline DrM

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I can't say whether it's all in your head or not.  What you have basically done is go around a safety feature that prevents you from starting the engine in gear without pulling in the clutch, and I can't say offhand whether it is just an isolated switch not connected to anything else, or it is connected to the ECU some way.  Someone more into electrical schematics may be able to chime in.  You have to ask yourself if the replacement clutch lever you have put on is worth the reduction in safety.

Offline taoster

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okay so i tried different methods:

Rode with the clutch switch unplugged: sounded different and didnt seem to have as much torque.

Rode with the clutch switch connected together: sounded normal, but exhaust started popping on deceleration, and bike was kinda of spotty and jerky while holding it at a steady RPM..

finally, i put my original clutch perch and lever back on, connected the clutch switch and it rides smooth as can be..

So, i've learned the hard way, YES, bypassing the clutch cable DOES effect fuel maps incase anyone else comes by this thread.

Offline lunkhead

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You must be hallucinating! That switch only controls the ability to start the motor while in gear. It doesn't do anything once the bike is running. All bikes have been using that switch for the exact same purpose forever.
C-SPƎC

Offline taoster

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I really wish i was hallucinating. Riding on the freeway the bike was cutting out everytime i was holding a steady RPM. Not cutting out as to completely lack of fuel, but a similar sputter. I'm out $140 for a clutch lever i purchased that i cant use because it effects the fuel map. Sure, the bike will run and get me from point A to point B, but the ride is not the same. This is the conclusion i came to. Please, by all means, feel free to experiment yourself.

Offline DrM

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You must be hallucinating! That switch only controls the ability to start the motor while in gear. It doesn't do anything once the bike is running. All bikes have been using that switch for the exact same purpose forever.
The color wiring diagram in the service manual does show a wire (black with yellow dots) going from the clutch switch (56) to the starter cut-off relay (18) and the ECU (32).  The second wire (green with yellow dots) goes from the clutch switch (56) to the fuel pump relay (19).

So it looks like the ECU could be involved - just saying.   

Offline lunkhead

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It's a switch that bypasses the neutral switch for starting, not a dual mode switch. Having the power characteristics change while you're trying to slip the clutch to take off would be stupid. Clutch switches have always had only one purpose and it's specifically for safety.
C-SPƎC

Offline taoster

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Do me a favor and unplug your clutch safety switch and ride around for a couple miles and tell me if you feel any difference. Maybe something is wrong with my bolt

Offline lunkhead

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If you don't have Ivan's flash, your bike can be in 3 different fueling modes. Open loop runs great because it uses the fuel map, closed loop runs lean under slow acceleration until open loop or fuel cut (when decelerating) kicks in where there's a noticeable kink transitioning because the engine goes from not running to running. I only have open loop mode with the flash so it always gets the right amount of fuel.

A better test for you would be to remove the switch but leave the wires connected so you can push the button at will. Go for a ride and push the button while holding the throttle steady. You should see a night and day difference if the switch is changing modes. I can do the same with mine but I have the flash.

I think the ECU connection is for the low voltage supply as it's coming off a bunch of diodes. The schematic is small and hard to see the symbols.
C-SPƎC

Offline lunkhead

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I really wish i was hallucinating. Riding on the freeway the bike was cutting out everytime i was holding a steady RPM. Not cutting out as to completely lack of fuel, but a similar sputter. I'm out $140 for a clutch lever i purchased that i cant use because it effects the fuel map. Sure, the bike will run and get me from point A to point B, but the ride is not the same. This is the conclusion i came to. Please, by all means, feel free to experiment yourself.

That's pretty convincing. If you're really feeling that much of a noticable difference, the clutch switch is probably always throwing it into closed loop mode. Everything you describe sounds exactly as it would feel. I could check it out on a stock bolt but I'll take you're word for it.

Do as DrM says and get rid of the switch and connect or leave disconnected the wires (whichever mimics clutch lever released). The only drawback is if you stall the motor while taking off, you can't just pull in clutch and restart.
C-SPƎC

Offline DrM

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Still should be able to shift into neutral and start,  which is the way I generally start.