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Expendable newbie
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Discussion Starter #1
The day of otherness I was riding on the freeway and something strange happened. I didn’t check my speed, but I was looking at the rpms. I going around 6K rpm in 5th gear and then suddenly the rpm dropped to 2K and went back up to 6k. This happened in the span of 1-2 seconds.

The bike behaved similar to when you brake very hard quickly or when you let go of the throttle and it engine brakes except it was way stronger. This wasn’t because I let go of the throttle because I had my hand on the throttle the whole time and I was maintaining speed. I tried to replicated it after it happened by letting go of the throttle, but it was nowhere as strong. I probably had about 25 to 30 miles to go until I needed to switch to reserve.
Any ideas what could have caused this? Is this a symptom of something?
 

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Maybe the puck in the ignition switch needs some attention. Loose wire on the back of the switch.

Can try nudging the key and see if it stalls, same with wiggling the harness and plugs near the bars and forks.
 

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I'm a rider
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964 Posts
If you were going or coming off an incline with that low of gas the petcock filter sits pretty high in the tank. It's possible you tilted it just below the available fuel supply. If it doesn't do it again or only when you are near an incline you may want to remove the petcock and check the filter for slime or contaminants. I wouldn't do it until it becomes an issue you can replicate once you figure out the potential cause.

If you were running for a long time at a constant speed vapor lock in the tank is a possibility as well. Check your tank vent for obstruction.
 
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2014 KLR 650!
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3,361 Posts
Maybe the puck in the ignition switch needs some attention. Loose wire on the back of the switch.

Can try nudging the key and see if it stalls, same with wiggling the harness and plugs near the bars and forks.
X2 on that. If it at all felt like the whole thing just turned off for a second, that's the puck. Soon it will leave you hangin. Happened ot me several times, on the highway in rush hour no less.

After you clean it, gorilla glue and tie wraps.
 

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Expendable newbie
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Discussion Starter #5
Damn you guys are good.

My ignition switch is faulty. If I turn the key too much to the right in the on position then it won't turn on. I have to turn it left a little so that it will turn on. Also if I turn the handle bar all the way to the right, then the bike dies. I know I have to take a look at the ignition switch, but I'm just too lazy.

Also I think I was going up an incline when it happened. My tank used to be rusty and I cleaned it out with vinegar/rust remover so I think there may still be some flakes of rust in the tank. I have in-line fuel filters and I can see the red flakes in there. My previous petcock didn't have the filters on the petcock so it let the flakes through the petcock and into the in-line filter. The petcock I have now does have a filter on it.

Another important thing I forgot to mentioned is that there was an incident before the power loss mentioned above. My bike had a minor power loss and stumbled similar to being out of gas. This random stumbling has happened before twice and once more after. It only seems to happen when there is less than 1/4 gas.
 

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FREEBIRDS MC CENTRAL NY
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Gettin' around don't mean you are good.just means ya know ****;)
 

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Damn you guys are good.

My ignition switch is faulty. I know I have to take a look at the ignition switch, but I'm just too lazy.
Should look into it, sudden stalls in a sharp turn can put you on the ground, or get you run over.
 

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FREEBIRDS MC CENTRAL NY
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Should look into it, sudden stalls in a sharp turn can put you on the ground, or get you run over.
Neither one is an option I'd prefer;)
 

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Neither one is an option I'd prefer;)
Aye .. yi-yi!

I quit riding mine with the plugged pilot jet because the power would come on unpredictably while making low speed turns.
 

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Expendable newbie
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Discussion Starter #10
Should look into it, sudden stalls in a sharp turn can put you on the ground, or get you run over.
Well thankfully I haven't experience that yet. The only time when I turn my handle bars to the right fully is when I am off the bike and pulling the bike out of the garage.
 

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Well thankfully I haven't experience that yet. The only time when I turn my handle bars to the right fully is when I am off the bike and pulling the bike out of the garage.
It cut out on the freeway, right? Hard to predict when or why the ignition will disconnect.
 

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Super Moderator
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Could have been POOGS. Check your gas tank vent.
If your bike dies when you turn the bars to one side, you have a bad connection or a broken wire, or are shorting out somehow (check the wires in the headlight shell)
If the switch is bad, what made it turn off and back on if you were going straight on the highway?

Sounds like you have more than one issue here...
 

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Expendable newbie
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Discussion Starter #13
I'm guessing that the rapid drop in rpm was due to the ignition. Maybe vibration caused it. Because of the rapidness of the rpm drop, it seems more likely that this issue is not fuel and is ignition.

I'm sure that I have a fuel issue too. Like I said before, my other issue is that my bike has stumbled and loss power similar to out of gas, but only for a second. Now this issue may be due to fuel. I have a CA model, so I don't know if I can be inflicted with POOGS. Can I?
 

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Discussion Starter #14
Well it happened again and I got to tell you, I’m going to need a new pair of pants and a new seat. This time it was worse. My fuel was over 70% and I was on a straight road. The rpm dropped to 0 and then back up. It was stumbling multiple times within an interval. At the worst point, the power was very weak. I opened the throttle all the way, but it felt like it was giving less than 50% power. The rpm maxed out at about 4.5k rpm. It stayed there for a while and I was gonna pull over, but it went back to normal.

I plan on addressing the ignition switch issue this weekend, but I want to know if I should look at anything else. The rpm was reading 0, but at that time I was still getting some power, only it was less than 50%. Could it be the jets were momentarily plugged with debris? Or maybe one of my cylinders weren’t firing? What else should I look at instead of the ignition switch?
 

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Well it happened again and I got to tell you, I’m going to need a new pair of pants and a new seat. This time it was worse. My fuel was over 70% and I was on a straight road. The rpm dropped to 0 and then back up. It was stumbling multiple times within an interval. At the worst point, the power was very weak. I opened the throttle all the way, but it felt like it was giving less than 50% power. The rpm maxed out at about 4.5k rpm. It stayed there for a while and I was gonna pull over, but it went back to normal.

I plan on addressing the ignition switch issue this weekend, but I want to know if I should look at anything else. The rpm was reading 0, but at that time I was still getting some power, only it was less than 50%. Could it be the jets were momentarily plugged with debris? Or maybe one of my cylinders weren’t firing? What else should I look at instead of the ignition switch?
If your tachometer is pegged at zero but your engine is still running, that indicates an electrical problem with your IC igniter box. Pin 4 (black wire on six pin connector) on the box drives ignition coil #1 as well as providing the signal to the tach. A wire that sporadically opens the circuit or a bad box would cause you to lose spark to one cylinder.
 

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If your tachometer is pegged at zero but your engine is still running, that indicates an electrical problem with your IC igniter box. Pin 4 (black wire on six pin connector) on the box drives ignition coil #1 as well as providing the signal to the tach. A wire that sporadically opens the circuit or a bad box would cause you to lose spark to one cylinder.
+1

also, related to that, check the connections on the pick coils, at the wiring harness, as well as check them under the cover on the left side of the bike.
 

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Expendable newbie
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309 Posts
Discussion Starter #17 (Edited)
I cleaned out my ignition switch (shown below) and I thought it was fixed, but it’s back and this time with a vengeance. At first I was able to turn the bike on no matter the position of the key and the bike doesn’t die any more with the handle turned all the way to the right. It was like that for maybe 1-2 days. Now, the bike will only start with the key turned closest to the off position, but still in on position. This is worse than before. Before I at least had a little leeway.

That is the least of my issues. After about 70-80 miles from when I cleaned the ignition, the bike had power loss again. Still the same issue as before where rpm drops to 0 and there is no accel power for 2-3 sec. Only thing I forgot to mention before was that it backfires like a shotgun, but I guess that is expected when it suddenly decel that fast. It doesn’t backfire all of the time though. This power lost issue happens only on the freeway.

This next one I feel is the biggest new issue. It seems to only happen when I’m city driving (not on freeway or at high speed). I really hope it doesn’t do this on the freeway. The bike dies and turn off like the kill switch was activated. This happened 3-4 times. I was able to start the bike up sometime when I was still in motion and then kept on going until it died again later on. One time I couldn’t start the bike up no matter how much time I pushed the button. I took the key out and reinsert it and then it started up.

I checked the IC ignitor and there was no resistance between the pins, except between 3 and 6. More info at IC ignitor box with no internal resistance. When I measured the ignition coil primary winding, I was getting either 23 or 230 ohms, I forgot, but it was definitely not in the K range. Both of the coils measure about this amount. The connection on the front ignition coil was reversed before but I corrected it. Also the bike is consuming oil like a baby consumes milk or like a prostitute consumes …, well you know what I mean.

What do I do now?
 

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Super Moderator
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when you cleaned the ign switch, did you remove the puck from the lock, take it apart (carefully, so the balls dont get lost), and slightly (very) stretch the springs?

or did you shoot contact cleaner into the lock?
 

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Expendable newbie
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Discussion Starter #19
I did a through cleaning. I took everything apart and brushed it and cleaned with acetone. It was shiny in the end.
 
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