Heh, I just meant that if the motor was connected to the wheels (clutch out), and the wheels were spinning, then the motor must have been spinning too. So the zero RPM reading is wrong, so there's an electrical problem.

 

Thanks, Maat!

Yeah I had this long response written about how the clutch was not engaged and then I realized what you were saying and it made sense that I had the definition mixed up from what you intended.

I guess Ill start looking this evening. Maybe Ill disconnect the PC3 and see if thats part of the issue? Any other ideas as to what I should be looking at? Still think it could be the battery or R/R?

Thanks again...

 

I don't think it's the charging system based on the tests you did earlier.

When the RPM's dropped to zero, and then the bike "started back up", did it go through the whole startup sequence like when you turn bike on? I know you were riding at 45 mph, so you probably (hopefully) had your eyes on the road.

If it did the whole startup thing, RPM needle goes all the way up and then down, bunch of lights on, all speedo segments displayed (i.e. it shows 8's) etc. then it's probably just a loose connection somewhere. If the whole LCD stayed on, but the RPMs just dropped to zero (and then came back), then you've got a weird problem. In that case I'd probably start with removing the PC3.

 

Damn...apparently I have the weird problem. There wasnt any startup procedure to be seen. I wouldnt have noticed but it felt kinda like the bike lost power and the rpms went to zero. I kinda think the bike actually shut off and then restarted under its own power (being under load, with the clutch engaged). Otherwise, I dont believe I would have just noticed the RPM needle dropping and popping back up.

 

Ok, so it wasn't like you turned the key off and on. It was more like you hit the engine off switch, turned it back on, then restarted the bike.

The RPMs dropping to zero thing is still bugging me. I'm going to speculate pretty wildly. I think the only way the motor could be spinning and the tach would stay at 0 is that the computer thinks there's no way the motor should be spinning. Like if you hit the engine off switch while cruising on the highway, what happens? I bet it's the same thing, the tach drops to 0, even though the motor's obviously still spinning. So there's some signal somewhere that tells the computer that the engine is ready to go (just like the one that primes the fuel pump before you hit the starter), and this signal is being interrupted.

So if you agree with my wild speculation, then you'll want to take a closer look at how this signalling works. Again, I'm speculating even more, but the PC3 and ECU probably have a lot to do with it. My bet is it's a computer somewhere that's acting up, or a bad connection to one of these computers.

 

Ok, so it wasn't like you turned the key off and on. It was more like you hit the engine off switch, turned it back on, then restarted the bike.

Im 2nd guessing myself now, but I remember the bike actually turning off (no engine power) and then the engine restarting just a second later. All the while the other gauges worked (speedo, temp, etc).

The RPMs dropping to zero thing is still bugging me. I'm going to speculate pretty wildly. I think the only way the motor could be spinning and the tach would stay at 0 is that the computer thinks there's no way the motor should be spinning. Like if you hit the engine off switch while cruising on the highway, what happens? I bet it's the same thing, the tach drops to 0, even though the motor's obviously still spinning. So there's some signal somewhere that tells the computer that the engine is ready to go (just like the one that primes the fuel pump before you hit the starter), and this signal is being interrupted.

Ill entertain your speculation as it does make some sense.

So if you agree with my wild speculation, then you'll want to take a closer look at how this signalling works. Again, I'm speculating even more, but the PC3 and ECU probably have a lot to do with it. My bet is it's a computer somewhere that's acting up, or a bad connection to one of these computers.

Ill have to give it a look tonight and see. I wish it were a problem that occurred with more regularity or under a certain set of parameters. The bike rides just fine most of the time....until this happens so its hard to replicate the problem on demand to see if a fix has occurred.

FWIW, sometimes I will see the FI light, the bike will stutter, and then the FI light will go out and the bike will be back to normal (never dying). Also weird.

 

My wifes F4i had a similar problem, if we took it on a short jaunt and killed it, it wouldnt start back up id have to pop the clutch, however where it gets close to yours is when her battery died i could hear the fuel pump reprime itself, the clock would be reset and the FI light would be on. The reason your RPM gauge read "0" is b/c it relies on an electrical relay from the motor, so if you lost all power (i.e. a dead battery or a grounded out battery) the rpm would read "0" but as soon as the power was restored the fuel pump would prime itself, the FI light would come on, then restart if the clutchw as enguaged b/c the circuit was complete again and not being grounded out. I say check 2 things
1) make sure you dont have a short, a naked wire, or that your battery is shifting under the seat and making contact with the metal, or that your connections are making contact with metal (ws my wifes problem)
2.) bad as i hate to say it, check your fuel pump/fuel filter. if your fuel pump is getting clogged up that would make it stall out and when it stalled the vacum pulling fuel to the injectors would quit, hense dropping the trash that the pump picked up enableing it to get fuel again and start again.
just my suggestions. hope you get it solved.
Will
P.S. i think Matt is onto something with one of the ECU's messing up and not communicating with each other or a bad connection between the 2.

 

My wifes F4i had a similar problem, if we took it on a short jaunt and killed it, it wouldnt start back up id have to pop the clutch, however where it gets close to yours is when her battery died i could hear the fuel pump reprime itself, the clock would be reset and the FI light would be on.

Aside from the clock resetting, it does sound pretty similar. That said, it doesnt appear as if a certain ride time or distance causes my problem to occur.

The reason your RPM gauge read "0" is b/c it relies on an electrical relay from the motor, so if you lost all power (i.e. a dead battery or a grounded out battery) the rpm would read "0" but as soon as the power was restored the fuel pump would prime itself, the FI light would come on, then restart if the clutchw as enguaged b/c the circuit was complete again and not being grounded out.

My only issue with this is that some times I will see the "FI" light illuminate as the bike feels a bit like its breaking up (like detonation...but its not) but doesnt shut off. That would indicate that maybe something is clogging the filter as you said. However, if it were the case, wouldnt it get sucked down towards the filter pretty much immediately every ride and almost right away?

I say check 2 things
1) make sure you dont have a short, a naked wire, or that your battery is shifting under the seat and making contact with the metal, or that your connections are making contact with metal (ws my wifes problem)
2.) bad as i hate to say it, check your fuel pump/fuel filter. if your fuel pump is getting clogged up that would make it stall out and when it stalled the vacum pulling fuel to the injectors would quit, hense dropping the trash that the pump picked up enableing it to get fuel again and start again.
just my suggestions. hope you get it solved.

Thanks. Had it not poured rain from the minute I got home until now I would have been outside tinkering..but without a garage it makes it tougher. To say I hate meterologists and weathermen would be such an absurd understatement. Somehow their guarantees of a beautiful day in the 80s turned into gloomy skies all day and rain all evening. I wish I could suck so hard at my job and yet be praised the 1x a week I did something well in the office (end rant!).

Im going to unplug the PC3 and see if that doesnt change anything as well as to look at the battery again...maybe the connection from the PC3 to the negative post of the battery is somehow causing this??


P.S. i think Matt is onto something with one of the ECU's messing up and not communicating with each other or a bad connection between the 2.

Im going to check this out tomorrow with any luck.

Thanks Will and Maat both!

If anyone else has any suggestions, feel free to share.

 

Check for rust in the tank?

 

fi light won't blink by itself, you need to jump the diagnostic plug which is in the tail cowl at the left, black small plug with two pins..