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I am currently converting my race bike back to a street bike. When I was done installing the lights, horn, etc.... I went to start the bike and nothing. Then I realized clutch switch needed to be engaged, so I closed the switch with a piece of wire and it started straight away. So my question(s) is.....
Can I permanently close this circuit, and if so, could there be any possible side effects, or should I find the parts and put it back to stock?
 

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I was told the clutch switch can be 'bypassed' with a relay. Not exactly sure how to go about it, but I was told this by the folks at the dealer I bought my bike from.

Would make it so you don't have to pull your clutch lever in to start the bike everytime.
 

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What was finally determined on the other thread is that the connection at the ECU from the starting circuit is passive. That is, no signal passes from the ECU when the clutch safety switch is either open or closed. A signal is fed to the ECU when both the clutch safety switch is closed (lever pulled in) AND the starter push button is depressed.

So you can just short out the switch.
 

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So you can just short out the switch.
I just read the other thread through. While the conclusion appears to be correct regarding starting and running the engine, I don't think all possible issues were settled.

1. If the engine is running and you accidentally push the starter button, I think the starter will engage if the clutch switch is shorted. I'm not gonna test it - that could damage the starter - but I don't see what would stop the starter relay from energizing and sending current to the starter.

2. The function of the wire to the ECU wasn't settled, as far as I can tell. With the clutch switch in place, when the clutch is pulled the wire to the ECU is grounded. When the clutch is out and the engine is running, that wire just floats because it leads to two open switches (clutch switch and starter switch). It seems possible to me that there's circuitry in the ECU that can detect whether the clutch is in or out when the engine is running. This might be used to protect the engine from going way past redline when the clutch is pulled and the throttle is opened wide abruptly. (The same protection likely would be applied when the engine is in neutral, via a separate sensor.)

Because of these issues, as well as speculation on this forum that the switch might be used to activate a different fuel map, I decided to install a separate switch when I installed a CRG clutch lever a few years ago. (I switch it on to start and off once the engine is running.) I've flicked it on and off under a variety of conditions and I don't see any difference in how the engine performs, so I don't think the wire to the ECU is used to alter the fuel or ignition maps. I think it's there to protect the engine from operator mistakes.

I'm not going to remove the switch, but I wouldn't bother installing a separate switch if I were installing the CRG today. I'd just cut off the clutch switch and solder the wires together. After all, none of my previous bikes had a clutch switch, and I never pushed the starter button with the engine running or floated the valves with the clutch pulled in.
 

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you can try, you will not damage starter. it will just spin fast doing nothing. motor is spinning faster than starter is turning starter gear. gear can not catch motor so it just spins free.
engine does not need more than one protection circuit, it cuts fuel at set rpm, regardless you in neutral, clutch in or out, with load and without load.....
only time it will not protect engine is when you downshift in lower gear while in to high rpm's and drop clutch.
 

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Actually, I meant the starter gears, rather than the starter motor. Maybe it's just another myth, but when I was leaning to drive it was emphasized that one shouldn't engage the starter with the engine running.

The rev limiter would have to react a lot faster if the throttle is snapped full open with the clutch pulled in than it does when the engine is driving the bike. Maybe it can react fast enough to prevent excessive revs, or maybe that wire is there to cut fuel a bit earlier when the clutch is in. One thing I didn't do is compare the rev limiter with my switch on vs off, so I'm not saying this is true. But, none of the explanations for this wire in the other thread made any sense to me, and this one does, a little.
 

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Actually, I meant the starter gears, rather than the starter motor. Maybe it's just another myth, but when I was leaning to drive it was emphasized that one shouldn't engage the starter with the engine running.

The rev limiter would have to react a lot faster if the throttle is snapped full open with the clutch pulled in than it does when the engine is driving the bike. Maybe it can react fast enough to prevent excessive revs, or maybe that wire is there to cut fuel a bit earlier when the clutch is in. One thing I didn't do is compare the rev limiter with my switch on vs off, so I'm not saying this is true. But, none of the explanations for this wire in the other thread made any sense to me, and this one does, a little.
Starters on motorcycles are different than on cars. On bikes the gears are always in contact and there is a starter clutch that lets it spin freely in the one direction.

In fact some people say hitting the starter button for a few seconds will help "alert" stop lights that you're there.
 

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Actually, I meant the starter gears, rather than the starter motor. Maybe it's just another myth, but when I was leaning to drive it was emphasized that one shouldn't engage the starter with the engine running.

The rev limiter would have to react a lot faster if the throttle is snapped full open with the clutch pulled in than it does when the engine is driving the bike. Maybe it can react fast enough to prevent excessive revs, or maybe that wire is there to cut fuel a bit earlier when the clutch is in. One thing I didn't do is compare the rev limiter with my switch on vs off, so I'm not saying this is true. But, none of the explanations for this wire in the other thread made any sense to me, and this one does, a little.
between starter driven gear and rotor there is clutch, bearing kind device, that locks starter gear with rotor. it is one way clutch and locks in one direction. once you release starter button starter stops turning and this gear stops turning. rotor is turning and gear just sits there stationary.
limiter does not react faster when you snap throttle with no load on engine, you just get to it faster. even manual will tell you not to bounce on rev limiter without load on engine.
 
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