Strange, very quiet motor noise upon shutdown

[MrPepsi]

So I had something strange happen the other day, that I think may have triggered my battery to drain. That in turn made me pull my battery to charge it, which also triggered this thread where I bugggered up a bolt real good.

I have a nearly stock 2009, that does NOT have the flies removed. No PCV, or cruise, just a slip on and 32,000 miles.
So the other when I arrived at home from my 24 mile ride from work I turned off the bike. As I pulled off my gear I could hear a very faint motor turning on for about five seconds, then off for another five. Then back on, then off. Very faint, coming from around the top of the engine. I clicked the stove knob again, and I could hear the fuel pump, VERY different noise. Clicked the stove knob back off again, and I could hear it again. I assumed it was normal and went back in the house. Well that is when the rain came, and the bike sat in the garage for about five days. Went to ride yesterday, and the battery was dead. Bike is only 2.5 years old, and Mama Kawi says the batter has a life of 5 years. I don't use a tender, as I ride every week, usually 3-4 times per week for rides over 25 miles. Never had an issue with the battery so I think this noise drained the battery. After charging the battery, the bike stated and ran perfectly, and no noise at the end of the ride. Had 14.1-14.4 volts the entire ride.

Anyone else hear a noise like that?

[VirginiaJim]

Well, actually the thingy making the noise drained the battery.  This could be why some others have mysteriously drained batteries as well.  Good catch on the noise.

[Shoe]

 

[Big B]

Not that I have been on my bike since November, as it is winter here.
However, I have encountered a strange noise on occasion. The noise was coming from the fuel tank itself. I opened the tank, released some vacuum, and the noise went away. Now I can't see any relationship with that noise to a dead battery.
BB

[MrPepsi]

Not that I have been on my bike since November, as it is winter here.
However, I have encountered a strange noise on occasion. The noise was coming from the fuel tank itself. I opened the tank, released some vacuum, and the noise went away. Now I can't see any relationship with that noise to a dead battery.
BB

Living in California, I'm very familiar with tank expansion. This was a motor, turning on then turning off. If you weren't listening for it, you might have not heard it.

[jayke]

Are the flies controled by a electric servo motor? TPS sensor?

Sorry, Never heard it on  my '08

[MrPepsi]

Yes the flies are controlled by a servo and this was suggested by Jim Pavlis as a possible source.

[ZedHed]

Are you sure it isn't the sound of the gas cap venting?  It makes a real funny noise that could easily be mistaken for the sound of a "tiny motor"  Next time you hear it, put your ear close to the top of the gas cap and listen......

[MrPepsi]

Did you read all the posts?
No it is not the tank venting.

[Gearhead82]

There is some kind of motor or air pump that's a part of the emissions system that pumps air into the exhaust.  That system sits right below the air box on top of the engine.  It's #16126 on this diagram towards the bottom/center.  I wonder if it has something to do with this.

http://fiche.worldofpowersports.com/wps/showmodel.asp?Type=13&make=kawasakimc&A=86&B=5

[Gearhead82]

Also, I wouldn't automatically assume that your battery is good just because you had 14+ volts while riding, especially since you had just charged the battery.  You might want to take your battery someplace to have it tested or just leave it sitting for 5 days again to see how it behaves.  If it turns out your battery really was bad then you might be stressing over nothing trying to track down this noise (not that it wouldn't be driving me crazy as well).

[MrPepsi]

Now we're talkin!

[ZedHed]

There is some kind of motor or air pump that's a part of the emissions system that pumps air into the exhaust.  That system sits right below the air box on top of the engine.  It's #16126 on this diagram towards the bottom/center.  I wonder if it has something to do with this.

http://fiche.worldofpowersports.com/wps/showmodel.asp?Type=13&make=kawasakimc&A=86&B=5

I think that is vacuum controlled?  The exhaust has no tubes or fittings to inject air, unless it is done in the exhaust port.  I think that is the crankcase vent system that is vacuum controlled.  I'd still be willing to bet that it was the gas cap vent and that is why you don't hear it all the time.  My OEM battery "dumped" in less than 2 years....

[MrPepsi]

I'd still be willing to bet that it was the gas cap vent and that is why you don't hear it all the time.

Wow, I must be some sort of idiot then. THis was not a whistle, this was NOT the tank. I got down on my hands and knees next to the fairing and I could hear an electric motor turn on for five seconds, then turn off. Then turn on, then off. I'm not sure what else I can say to convince you this was not the gas tank venting through the cap. Hopefully everyone else believes me though.

[Gearhead82]

I think that is vacuum controlled?  The exhaust has no tubes or fittings to inject air, unless it is done in the exhaust port.  I think that is the crankcase vent system that is vacuum controlled.  I'd still be willing to bet that it was the gas cap vent and that is why you don't hear it all the time.  My OEM battery "dumped" in less than 2 years....

It does inject air directly into the exhaust ports I believe.  And I'm almost certain it's controlled electronically.  The hose (92192C on diagram) connects right into the air box and that's the hose that gets plugged for those of us who have aftermarket exhausts and wanted to stop the loud "popping" we get on decel.  Then on the other side of that valve there are hoses that distribute the air to 4 inlets on the head that connect to the exhaust ports.  I remember looking at the whole system when I plugged that hose.

[ZedHed]

Wow, I must be some sort of idiot then. THis was not a whistle, this was NOT the tank. I got down on my hands and knees next to the fairing and I could hear an electric motor turn on for five seconds, then turn off. Then turn on, then off. I'm not sure what else I can say to convince you this was not the gas tank venting through the cap. Hopefully everyone else believes me though.

OK -- I believe you already -- I was just trying to look for a simple solution, not call you stupid. 

[ZedHed]

It does inject air directly into the exhaust ports I believe.  And I'm almost certain it's controlled electronically.  The hose (92192C on diagram) connects right into the air box and that's the hose that gets plugged for those of us who have aftermarket exhausts and wanted to stop the loud "popping" we get on decel.  Then on the other side of that valve there are hoses that distribute the air to 4 inlets on the head that connect to the exhaust ports.  I remember looking at the whole system when I plugged that hose.

Which part # is the motor?  That hose vents fumes from the top of the engine into the airbox to be burned and not vented to the atmosphere, nowhere does it hook to the exhaust.

[MrPepsi]

OK -- I believe you already -- I was just trying to look for a simple solution, not call you stupid.

Its all good.

[Gearhead82]

Which part # is the motor?  That hose vents fumes from the top of the engine into the airbox to be burned and not vented to the atmosphere, nowhere does it hook to the exhaust.

Then why does plugging that hose eliminate the backfiring that happens on decel?  Here's a pic of a ZX-14 combustion chamber.  The exhaust port on the right has the hole where the fresh air is injected into the exhaust.  It introduces oxygen to assist in burning off any unburned fuel in the exhaust system rather than send that unburned fuel out the tailpipe.

[Gearhead82]

Actually that last pic was a ZRX cylinder head.  Here's a ZX14 head with the same port visible.