gel battery riding time - bad alternator.

[Texas Cajun]

Hey All,

Need some experienced advice.  Alternator is bad (11.3 volt output), new one is on order but have really important charity ride coming up that I don't want to miss.  If I buy a new gel battery, how much riding time can I expect with just headlight /taillights before the battery dies?

[Chrisj CMA]

With the alternator putting out 11.3 you should have all day no problem.  If you are in a group ride and its only during the day you could pull the fuse on the headlight and just stay in the pack, put the fuse back in to ride home........but a new battery and some output on the alternator I think youd make it just fine.

[Chrisj CMA]

Not trying to insult your diagnosis of a bad alternator, but I have never heard of one going bad in this way (reduced output)   Have you checked the brushes, 50,000 shouldn't be enough to totally fry the brushes but its around the time they can be near the end.  How about all the connections, the ground and battery connections, clean and tight could make a difference.  Also did you verify the 55A fuseable link was good?  That 11.3 could just be a battery reading

[BonS]

My alternator was completely dead. After putting in a new AGM battery into my Interstate I got about 17 miles before it was exhausted. Had I pulled my headlight fuse I think I would have maybe doubled that. Maybe.

An alternator can put out a reduced voltage under the right circumstances such as a failed diode or a shorted winding. Bad brushes will cause the output to be intermittent and, on average, result in a reduced charge rate or no charge at all.

[Texas Cajun]

The 11.3 was at the alternator itself.  Ground looks good.  I'm expecting it is the bushes but I'm not the most mechanically inclined.  Easier for me to replace and then have time to tear in and rebuild the oem

[Texas Cajun]

Increasing engine rpm had no effect on voltage output

[Texas Cajun]

Sorry for the multiple parts but I'm guessing it is intermittently charging.  At time my neutral indicator is bright and at other times it is not visible.  And modulating headlight is intermittent also.  55 fusable link looks good

[The emperor has no clothes]

When my alt. went out it was intermittently charging for a day before it completely gave up the ghost. I should have paid better attention to the signs but at the time I was battling snow and ice and in fear for my life

[Daniel Meyer]

I strapped a tractor battery on the luggage rack of a Honda 350 and rode all day once...

If you're reading 11.3 at the alternator, then that's also going to be very close to the battery voltage...and that's practically dead. I wouldn't ride it.

[JC]

I agree with Daniel, I wouldn't ride it until it's fixed. I had my alternator die right at 50,000 miles and found that a fully charged battery only got me 40-50 miles before the bike wouldn't run.

You mention that you have another on order, but if you check with a few of your local alternator shops I bet you'll find one to rebuild your old one like I did, then you'll have a spare. Cost me about $80 for the rebuild and it's worked fine ever since. Just have to make them aware that it is NOT off of a Goldwing or they may reassemble it as such, and you'll then have to rotate the front plate as is mentioned in a number of other alternator discussions on the board so it lines up with the Valk.

[Farther]

Check your grounds on the alternator, you may have a loose one.

[MarkT]

Having a similar problem, my Compufire 1.3Kw (90amp) is getting weak.  Installed a digital voltmeter some time ago.  The Compufire which is based on a Delco automotive unit, produced 14.8v at idle when new.  Recently it has been slipping all the way down to 11.9 at times.  I thought my voltmeter was failing as the Escort was reporting a volt higher.  I replaced the battery, gave it a full charge, then we went on a local 100mi ride with a lunch stop in the middle.  Got back to the local grocery, and had to push start it.

Several times recently, I put a full charge on it, then we went for a local ride - dinner or lunch.  Used only minimal lights and kept the audio off.  Just putting off the fix while we're getting the last of the great riding days for awhile.

IOW, if you ride before you fix it, put a full charge on the battery, use minimal juice and keep the ride short.  Might want to park on a hill.

On Deerslayer, it's likely the brushes are failing (per Compufire TS). Or whatever - as I'm doing the "shotgun fix".

Just pulled the Delco and sent it off to Compufire for a factory rebuild.  For only $120 (for a $429 unit new) they will just replace it with a new one - and use my core as the basis for some other build.  And I'll be good for another 100k miles.

[Wolfgang1952]

Replaced battery and alternator and still not charging.    Be riding and tac drops to 0 rpm.   Don’t have for before it quiets.   Won’t start till recharge battery, tac works on full charge

Wolf

[Gryphon Rider]

Replaced battery and alternator and still not charging.    Be riding and tac drops to 0 rpm.   Don’t have for before it quiets.   Won’t start till recharge battery, tac works on full charge

Wolf

Did I miss your previous post describing your troubles?  It seems your battery is fine but your charging system has troubles.  Probably the alternator rotor, but maybe cable connections or 55A fuse.

EDIT:  Sorry, I missed your second "and", reading in my head, "Replaced battery and alternator still not charging."  It's time to check all your connections between the battery, chassis, and alternator.

[gordonv]

Replaced battery and alternator and still not charging.    Be riding and tac drops to 0 rpm.   Don’t have for before it quiets.   Won’t start till recharge battery, tac works on full charge

Wolf

You replaced your battery and alternator, without discovering what was the actual problem?

So now you've changed them both out, I'll figure that they are working, and you still get a dead battery (and bike). Seems your battery is not charging.

First, I'll also figure that you do not have the service manual. Get one. Tells you how to figure out and the steps to take to diagnose what is wrong. (I'm fairly sure his site is still down [it is]).

http://valkyrienorway.com/download.html

I'm only going by memory, but isn't the 55 amp fuse between the alt and battery? So if the battery isn't charging, and all else is good, then check this dog-bone fuse. With a meter!

[Texas Cajun]

Just to update everyone, new alternator arrived at 3pm on.day of event.  Tore into bike at 3:30, had alternator replaced and tested by 4:30. (measured output of >14v),  had everything cleaned and buttoned up by 5 and was on time for the event.  3 weeks later, everything seems to be operating OK.

[Firefighter]

No!,, your still having trouble, you just can't except that,, and we are going to help you! Firefighter