Jump to content

'98 Vfr Battery Drained, Even While Running, Now Won't Start


WoahThereThrottle

Recommended Posts

Hello all,

My '98 VFR's battery is dead and won't start, even though I've been running it constantly over the winter to keep it charged. Here's the whole story:

I haven't actually ridden it since the summer, but I've run it probably 6 times since then for about 15 minutes each in hope of keeping the battery charged. (I ran it in Neutral though, I'm thinking now if the alternator runs off of the driveshaft then none of this would have actually charged the battery unless I was in gear). I started it again today, it turned over a bit slower than the last time but started. Did some circles around the parking lot for 20 minutes (in gear of course), shut it off. When I started it again, it barely turned over, a clear sign the battery is just drained and the starter is still getting current when I hit the switch.

Why didn't the battery charge? Was it because I ran the engine in neutral? I know the rectifiers on these bikes tend to go bad is that related?

Thank you for the help, apologies for my relative lack of knowledge, this is my first bike :wink:

Link to comment
Share on other sites

  • Member Contributer

If you are going to not ride the bike, you need to put a tender on it. The few times you ride it are not enough to keep the battery charged properly, and when a battery is left uncharged for a period of time it will fail.

The biggest question I have is was the stock regulator ever changed, and if so, when and with what. If you are handy with a multimeter there are resistance tests posted on the forums/factory manual you can follow to determine the health of the rectifier.

My suggestions are as follows..

A. Get a battery tender. Charge the existing battery.

B. Have it load tested at AutoZone or equiv for free.

C. If the battery is bad purchase an AGM style battery and charge per the provided instructions. Keep the battery on a tender while you are not riding the bike.

D. Test your regulator anyways. If it has never been changed, now is a good time to look into a MOSFET unit and possibly the VFRness. (I purchased a Rick's MOSFET unit, and it works great. You can get it off of the same site as the VFRness as well).

Some notes: The stock regular does not charge barely any, if at all, at idle. You have to be at 3k RPM or higher for the stator to output enough AC power for the stock rectifier to charge the battery. MOSFET units will charge more at idle, and produce a steadier voltage of 14.3-14.9v at all RPMs. It doesn't have anything to do with it being in gear, but more about the RPM of the engine.

I knew reworking the electrical of my 86 Vulcan would come in handy. I also upgraded it to a similar MOSFET unit. However, nobody on these forums seems to be aware of stator rewinds by Tim Parrot (www.tpe-usa.com) which are way better than buying a new replacement stator. He winds them tighter than OEM, so their power output is better. Unrelated to your issue, though.

Link to comment
Share on other sites

  • Member Contributer

'98s and '99s are notorious for eating OEM R/Rs and chances are yours is gone. That said, go buy a multimeter and learn to do the tests below. And also inspect the stator connector, they have a history of burning up. You need to pull the tail body work off. Oh yeah, a Battery Tender is a good investment too.

Steps:

- Recharge battery overnite - then to take it to Autozone, Batterys Plus or similar to load test. -- Good? Bad? – An iffy battery can fake you out and act like a bad R/R. Buy new if needed.

- With good battery fire it up, warm up for a minute or two.

These are R/R quick checks---

--- With voltmeter at battery posts get voltages -- idle volts? 5000 rpm volts? What’s the numbers? Should be in 13ish min idle and in 14s at revs. If in the 12s at idle, try at 1900 rpm. (It's not unusual for the system to be in discharge or no charge at idle.)

- Check stator

- 1. Pull connector apart. Set meter to resistance. Check pin to pin, on the stator side connector. 3 yellow wires, A to B, B to C, C to A. What’s the numbers? 3 separate readings --Should be less than 1.0 ohms. (Engine off)

- 2. Check continuity from each A,B,C pin to ground, -- -should be infinity - nada nothing. no continuity. -- 3 separate checks. (Engine off, again checking stator side connector and apart)

- 3. Crank it back up. Do another pin to pin thing, but set meter on AC volts. idle and 5000 rpms. What's da numbers? Should start 15 -20ish and climb 50ish and more. Again – 3 readings on the stator side connector and still apart.

- Repeat hot.

This procedure has helped many fellow vfr guys, online and here locally. I like it 'cause, it's keep it simple stupid and it works.

This quick list will catch the obvious stuff, but if you need to dig deeper check this chart. (Some guys here like it, I dont care for it.)

http://www.electrosport.com/media/pdf/fault-finding-diagram.pdf

If this seems over your head, find a buddy that can help. Really need the numbers to tell whats going on, but my bucks are on the R/R.

Also, please list your mileage.

Link to comment
Share on other sites

  • Member Contributer

:1:

To what the others said, + if you ever need a hand feel free to give me a call, I am a little north of you

Gary

425-343-4678

Link to comment
Share on other sites

  • Member Contributer

If it were my, I'd suspect (in this order) battery, RR, wiring harness, stator. All of these can contribute to your symptoms. Mello Dude's guidance is accurate.

Regardless of what the faulty part is, I would highly suggest a VFRness and an onboard voltmeter. A VFRness has helped stablize both my voltage and my brother's. And an onboard voltmeter helps to identify issues before they become problems.

One last thing. When it comes to AGM batteries, I've heard that one deep discharge can leave you with a five pound paperweight. I know this is the case with automotive spiral cell batteries.

Link to comment
Share on other sites

  • Member Contributer

One last thing. When it comes to AGM batteries, I've heard that one deep discharge can leave you with a five pound paperweight. I know this is the case with automotive spiral cell batteries.

Absolutely correct on that note. A battery tender is a must if you don't ride frequently and have an AGM style battery. I let one go for 2 and a half months and that's all it took to really kill it.

Oddly, Walmart's EverStart AGM batteries are pretty darn good, and usually readily available.

Link to comment
Share on other sites

  • Member Contributer

I will also add that running the bike for short periods without riding it is one of the worst things you can do to it. Either ride it at least 10 miles or leave it be. If you're gonna do the latter change the oil, and add some stabilizer to the tank before your last short ride. Top the tank off when you park it.

Link to comment
Share on other sites

I will also add that running the bike for short periods without riding it is one of the worst things you can do to it. Either ride it at least 10 miles or leave it be...

sounds like a good excuse to go for a ride!

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy.