This might be long winded but bare with me.

I was riding home from work on Sunday. It was hot around 108 or so and the bike started acting like it was running out of fuel. I bend down and put it over reserve and it died. So I'm on the side of the freeway and trying to start it after verifying it had fuel, no luck. I take my helmet off and turn the kill switch to on and I can here the fuel pump going like crazy and not shutting off. After cycling it on and off a bunch of times it finally came to a hault and stop running (assuming it finally built up pressure). Bike then fired up and I drove home. Well yesterday I was riding it home and stopped at a tire shop. Came back out and the bike wouldn't start, once again the fuel pump would not stop running. I pulled the side panel off and pulled the outlet of the fuel pump off and their was no sign of fuel (full tank by the way). Well I ended up killing the battery. Called the wife and got towed home. Put a charger on it and bam the bike fired up (at this point it was loaded up). I left the charger on it for awhile. Came back out and fired it up and noticed the battery voltage going from 12.6 to 12.3 and it held there. Thinking the regulator might be bad along with a bad fuel pump??? I did some checks, I measured voltage from the red/white wire to the green on the plug and I got battery voltage and then measure resistance on the yellow wires and got 8 to 900 ohms (books says that's good). I checked the regulator and everything measures in the 25 Meg ohms, books says yellow to yellow it should be around the 500kohms range or so. Any thoughts? I'm thinking I may have killed the battery but it doesn't seem to be charging once it started well not 13v anyways. Any thoughts would be appreciated!!!

 

If you checked the voltage and the bike was idling, then the voltage will be that of the battery. If you have the RPM above 2K or so, you should have a measurement that is significantly larger than the battery voltage. You might also want to have the battery tested. The CCA on the battery is 120.

 

I rolled the throttle up to 5k and their was only a tenth or so increase. Nothing that was even close 13v's.

 

regulator/rectifier and stator may be toast. Honda has been known to sacrifice electrical capacity for weight savings. But going to 5K rpms you should be putting out high 13 to low 14 V.

Not sure if that is what is giving you the fuel issues. Does your bike have a fuel regulator that dumps extra fuel to the tank? If so I'd start with it. Usually if the fuel pump goes out it's out. Rare to have it die and then get better all by itself.

 

I'll chime in here with an idea, The reg issues with this bike are so well known, but the reg problems come about from them overheating. When mine started going south, it only acted up once the thing got hot. So testing the reg while the bike had been sitting will/may give a normal reading, try a quick blat & then test the thing before moving on to the battery.
Eventually the reg on mine just totally shat itself all together, but not before I had forked out $120 on a new Yuasa.

 

No regulator. I just find it strange that it never shuts off at times. I was reading in the manual and it said something about vent tube being plugged, have you guys ever have one plug up? I'm going to start with the R/R and go from there. I did the checks in the book and it steered me to the R/R. Charging system seemed to check out.

To be honest, this thing has acted up twice now where it just died and it would start and run like it's missing and then not run at all. Then all of a sudden it would start so I said screw it and order a GSXR R/R today just to crossed that off the list.

 

Also, I was screwing around with it while I got it running again. I unplugged (I know, I shouldn't do it but life's a beach) the R/R while it was running and the RPM's came up a hundred or two. It also started A LOT better. Then when I plugged it in again it bogged it down. I'm sure it was charging the battery, just find it pretty interesting!!

Thanks for the replies!!!!!!!

 

That's definitely screwy ... sounds like the R/R is bleeding off too much current. Basically, they turn excess current into heat to avoid frying the battery. Apparently yours is not charging the battery (because of the 12.3V while running) and turning all the current into heat.

 

How were you testing the yellow wires ? I think you may have misread something. Going from yellow to yellow, you should read .1 to 1 ohm (thats "point one" or a tenth of an ohm to one ohm). If you're reading 8 to 900 ohms (I’m not sure if you mean 800 to 900 or actually 8 ohms to 900 ohms), then you either have bad connections, a faulty meter, or a bad stator coil. Those yellow wires are just coils of wire, with essentially no resistance at all. Look at page 15-8 of the shop manual. Now, that not withstanding, these bikes are notorious for bat R/R's and I wouldn't be surprised that it's going bad.

As for the fuel pump, on these bikes, when you turn the key on, the fuel pump does not turn on. The pump doesn't actually run until you start the bike. If it's continuously running, then you probably have shorted fuel cut relay, or it's been bypassed to provide voltage to the fuel pump continuously. If the pump is always running, then it could easily run your battery down.