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Discussion Starter #1
I was racing with a group of friends at a lake. And I was racing my bike pretty hard, and at the end of our group ride my rc decided to do a backfire popping sound from the pipes. While doing that, my FI light would stay on solid for 3-6 seconds and turn my bike off.

This happened every time. My Rc stays on in neutral, but the problem seems to be it shuts off when i put it in gear (doing so would turn FI light on and shut the bike off instantly). I even had it in gear before i would start it, which allowed me to take off but only for 10 yard until my FI light would come on and shut my bike off.

Why??:(((
 

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Discussion Starter #3
Does it have a PCIII on it? disconnect and check running condition after.
Do you have a picture of this PCIII ?
She starts up without hesitation and idles just fine.
So it must be something easy i assume, its just taking off is the problem.
She'll start to sputter and then shut off.

She was riding like a beast yesterday, but i did ride fast through some really hard bumps. maybe it could have disconnected something?
 

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I'd check your:
1) Battery posts connections to ensure they're nice and snug.
2) Sidestand switch to ensure it's working properly
3) Clutch switch to ensire it's working properly.

Since the bike seems to die when you place it in gear, it may be the clutch or sidestand switches might be faulty.
Along with the neutral switch, they make up the safety interlock system.

The engine dying while riding could be loose battery posts causing a brief loss of power to the ECU, which then resets.
Did you notice if your tachometer did a sweep cycle, as it does when you initially switch the key on?
 

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Discussion Starter #5
I'd check your:
1) Battery posts connections to ensure they're nice and snug.
2) Sidestand switch to ensure it's working properly
3) Clutch switch to ensire it's working properly.

Since the bike seems to die when you place it in gear, it may be the clutch or sidestand switches might be faulty.
Along with the neutral switch, they make up the safety interlock system.

The engine dying while riding could be loose battery posts causing a brief loss of power to the ECU, which then resets.
Did you notice if your tachometer did a sweep cycle, as it does when you initially switch the key on?
The battery, sidestand switch and clutch switch are fine.
I double checked to see if they were fine, disconnected and reconnected things to make sure everything was ok.

It sometimes shuts off when I put it in gear, but not all the time.

I havent done anything to the ECU yet, not even sure what it actually looks like either. Yes my tachometer did a sweep cycle like normal when I turn the key. My bike stars up fine in neutral and will stay on. Taking off the issue
 

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PCIII is the power commander, I'm guessing you probably don't have one on there if you don't know what it is.
When the bike shuts down does the odometer reset too? Look into the service manual under the TS section and look up the symptoms your bike has. It will help a lot with looking over where everything is routed thru.


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Discussion Starter #7
PCIII is the power commander, I'm guessing you probably don't have one on there if you don't know what it is.
When the bike shuts down does the odometer reset too? Look into the service manual under the TS section and look up the symptoms your bike has. It will help a lot with looking over where everything is routed thru.


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Yeah I dont have a power commander.
When my bike shuts down, the odometer does reset, and my fuel tank/injection
will prime like you do when you first turn the bike on.

I cant seem to find an rc51 service manual online. any direct links i can go to?
 

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1) You could have problems with the engine kill switch on the right bar.
2) You could have wiring problems.

You stated that when the engine problem occurs, the ECU initializes and fuel pump primes as if the ignition was switched off and then on.

I'd also check the wiring harness on the left side, under the fuel tank.
Where the harness passes over the rear frame section, it's very near the bottom seam of the fuel tank.

It's very easy to pinch wiring at that area, causing momentary opens, which it seams you're having.
Not an easy thing to troubleshoot. But it's happened in the past.

I know when I was working on mine back in '08 I noticed this, and took quite a bit of time to try and route and secure the harness to prevent this.
Even now, if I raise that tank, I SLOWLY lower it and visually check all's clear.
 

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Discussion Starter #10 (Edited)
1) You could have problems with the engine kill switch on the right bar.
2) You could have wiring problems.

You stated that when the engine problem occurs, the ECU initializes and fuel pump primes as if the ignition was switched off and then on.

I'd also check the wiring harness on the left side, under the fuel tank.
Where the harness passes over the rear frame section, it's very near the bottom seam of the fuel tank.

It's very easy to punch wiring at that area, causing momentary opens, which it seams you're having.
Not an easy thing to troubleshoot. But it's happened in the past.

I know when I was working on mine back in '08 I noticed this, and took quite a bit of time to try and route and secure the harness to prevent this.
Even now, if I raise that tank, I SLOWLY lower it and visually check all's clear.
okay, so i disconnected the ECU box i believe, disconnected and reconnected. Took the bike for a quick spin and had no problems. going to to a bit further and we'll see how it goes I guess.

?
 

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Be proactive, and buy a tube of dielectric grease at your auto parts store.
Use it on every electrical connection you can.
It prevents moisture related corrosion.
And bikes that are exposed to humidity or get caught in rain are very likely candidates for corrosion.
Highly recommended!
 

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Discussion Starter #12
Okay so i have come to conclusion that the reason my bike keeps on shutting off is due to some sort "loose connection or cable".

I took my bike for a quick spin, and i purposely hit bumps to see if it would make my bike shut off. Every bump that I hit would make my bike turn off. And when I was on a nice flat surface she rode without a problem.

So what cable or connection could be lose thats causing this?
 

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My guess is the wiring under the tail fairing and left fairing. Something is running loose and may need to be supported. That grease stuff should work great too if you get the chance to use it.


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Discussion Starter #14
My guess is the wiring under the tail fairing and left fairing. Something is running loose and may need to be supported. That grease stuff should work great too if you get the chance to use it.


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I had a friend come over and help me out, we actually got lucky and found what it was. my bike wasnt priming after a while, but with a couple minutes of moving cables side to side, we got it to prime.

There was a wire that was melted off on the left side of the bike close to the break lights. So we got that sucker back in there and she rides fine! :)
 

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It's called dielectric tuneup grease.

It's silicone based and non-conductive, and is used to protect electrical/electronic contacts from moisture related shorts or corrosion.
It's a factory maintenance requirement on new cars these days.

Long before that, it was military issue for use with special sealed butt splices used with torpedo guidance wires.
The splices were used to join the end of the torpedo internal guidance wire spool to the matching spool that remained in the torpedo tube after firing.

With a proper crimp and use of the dielectric grease, the splice was not only stronger than the wire itself (wire would break before crimp did), but it was also waterproof down to...well lets say, very deep.

I started using this stuff when I replaced my wiring harnesses due to the moron who owned it before me.

Besides the butchered undertail and front turn signal job he did (reason for harnesses replacement), I also noticed that some relays and connectors that were exposed to rain or condensation were green due to corrosion.

Once the harnesses were installed, every connector got a liberal dab of the dielectric grease.
I have had zero electrical problems due to corrosion or moisture, despite repeated washings or being caught in rain showers.

One 6 oz. tube should last practically forever since it doesn't take much.
I bought two thinking the bike was going to need a bunch of it.
But one 6 oz. tube has lasted me several years.
 
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