vfr800_red

Update: Yes, I’ve done all the above tests, and the fault was low AC voltage output so as Grumm mentioned this would be 2 phases shorted together. This failure is not documented in the manual, and my 2nd stator which had this failure. Each lasted about 40k miles, so not bad. I was confused a little by the manual because page 16-12 describes checking that each stator phase is not shorted to ground as an R/R test. Also was a little confused because the OEM R/R has a 4 pin output, but the MOSFET R/R has a 2 pin output. It has been 12 years since I’ve seen the OEM R/R, but I understand now they just doubled up the wires. 5th gen OEM stators are no longer available, so I purchased an inexpensive aftermarket stator on Ebay, Caltric, which includes a new gasket. I know sometimes aftermarket parts are lower quality than OEM, but the seller has a 97.6% positive rating. Put it on the bike last night and have 60VAC @ 5k rpm across all 3 phases. Didn’t have any problems removing the old gasket. I should solder the wires to the MOSFET R/R later today, finish assembly on the remainder of the bike, and if the weather cooperates, be riding this weekend. It is late in the season where I live. Great information about the 6th gen stator and flywheel, I assume that OEM of those are still available. Maybe I’ll go ahead and purchase these as I’d like to keep the bike going for many more years. Here’s a trick could help remove the flywheel nut: remove a spark plug then place rope in that cylinder. That worked well when I torqued a crank pulley on a Toyota Camry. And I replaced the auto reset breaker with a 30A fuse holder. Nice to learn that, always wondered what that was. I don’t come here much, but this discussion group is an invaluable resource to keep these aging bikes going. I attempted to give a donation, but when I click the pay now button, it says “This organization can't accept donations right now “, perhaps because the total donations have exceeded the total goal. If so, I’ll set a reminder to make an early 2025 donation.

Ok, Thanks, I will get the fuse. R/R is Shindengen FH020AA.

All phases are open circuit to ground. Meter set to 2 million ohms. The R/R contacts are not burnt nor splayed. R/R output wire: I think this is a fuse, not a breaker, but I really don’t know. It came with Roadster Cycle Super MOSFET kit. Yes, wiring is messy because when the big undocumented ground connector melted a few years back, I soldered all the ground wires together and I found it easier to cut away the outside sheath. Last week on a ride I had to push start it after a fuel stop, but that was partly because of corrosion and melting at the main fuse connector and the downstream single wire connector. Main fuse and its connector have been replaced and Ox Guarded, and the single wire connector has been replaced with solder and heat shrink. Today on a ride, my voltmeter which is taped to top triple tree briefly reported < 12 V with rpm in the 4k to 5k range. I pulled over ASAP, disconnected the headlamps, and rode home with no issues, and the voltmeter typically displaying >14 V. Maybe I have a stator that is close to failing, and I simply need to ride it some more, while keeping a close eye on the voltmeter, and not take any long trips.

10V when connected to the R&R. I browsed here a little and it seems the incandescent light bulb test is correct only when disconnected from the R&R, and that voltage should be about 65 V. When I disconnect the R&R, my volts across each pole range from 28 to 35, which is low, but I didn’t try the light bulb test. Forgot to mention that yes, I have less than 1 ohm across each of the 3 stator poles. The R&R is a Roadster cycle Super Mosfet kit. There is battery voltage across the R&R black connector. The continuity test on page 16-12 of the manual doesn’t seem appropriate because my MOSFET R&R has 2 pins, not 3 pins. Attached pictures for reference.

Hi VFR guys and gals, I'm having charging problems. I think my stator is the problem. It is 12 years of age and has at least 40k miles on it. I know that engine heat causes stator failures. Per the factory manual, there is continuity across all 3 poles. Each pole produces about 10V which does seem low. The last time I had to replace the stator, 2, but not all 3, poles could power a 60 incandescent bulb. Now, none of the poles can power a 40W incandescent bulb. Part of the reason I suspect the stator is I have a MOSFET R&R, which have a rock solid reputation. My connectors are clean, no burning or corrosion. I removed the OEM connectors a long time ago.

Hi vfr800_red, Thank you for your donation of 25.00 USD. We look forward to improving the forums with your donation. Thanks VFRDiscussion

Yes, will get Ox-Gard and I'm all set. Thanks!

Hi Grum, It is the same fuse in Bren’s picture. However, my fuse was 20A, and it looks like Bren’s was also 20A. If that is main fuse B, according to the wiring diagram, it should be 30A. Should my replacement fuse be 30A? Thankfully, there is no corrosion at the connector and all other fuse connector are clean. But there is some gunk at the stater relay connectors so I will clean those up. And I’ll take a closer look at other nearby wiring. I’d never replaced that fuse, and I’ve had the bike for 19 years. It was probably original, and I like the explanation that fuses don’t last forever. For that reason, I will be replacing all the fuses.

Hi All, My 5th gen recently died when I was slowly pulling away from a stop in first gear, slowly letting out the clutch. The starter motor turned over fine, but it would not restart. I soon realized the fuel pumps were not energizing when they key was turned to ignition. The fuel pump fuse was fine. I followed the procedure in 5-58 of the factory service manual, discovered the fuel pump was not getting battery voltage, and traced it to a blown sub fuse. I replaced the sub fuse and everything is fixed, the bike starts and runs great and has had numerous restarts. However, I know that blown fuses are often a symptom of a more serious electrical problem. Any thoughts why the sub fuse would suddenly blow? I’ve never had this problem before. I noticed I didn’t have headlights when the sub fuse was blown, that is, it “shares” a circuit with the fuel pump. Thanks.

Don't have a sticky starter button, but I get it, don't need a picture, and I like it, clever. I will say a few more starts seemed better. But this has but on a brief hold as I've identified an oil leak and am now waiting on parts. Should send an update later in the week.

Hi, My 5th gen is having difficulty starting. I’m very confident the battery and charging system are fine. The battery is newish, and holding a charge, and charging system is delivering 14 V at 5000 rpm. Once the bike starts it runs fine. I suspect the starter motor is at fault. It is the original and has never been serviced –> the original brushes. Not only is the bike 24 years of age it has >85k miles. And I’m noticing more starter gear whine, I hear some whine even after the engine has started. Hoping I can get some thoughts and feedback before I start taking things apart. Thanks.

Ok, good to know. Thanks.

Yes, that looks like it will do it, but it's pricey. Thanks.

Hi All, I’m looking for a rear wheel stand recommendation for my 5th gen. I’ve had difficulty finding one on the web. Or if someone is interested in selling one.

I will chalk this up to a “what was I thinking” moment. I found that the connection to the throttle body is on the left, not underneath the airbox, and is easily accessible once the tank is lifted. For some reason I was convinced it was underneath the airbox. Problem solved.