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Ive noticed when riding that every now and then my battery light on the instrument cluster will come on. It will stay on for a few minutes at most then go off. Normally this happens just after I've been at a traffic light for a decent amount of time. Is this anything to be worried about and should I be startibg to price an alternator, or is this something that happens with the first gen Brutale? Thanks guys.
 

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From my layman's experience it does sound as if the battery is not receiving enough charge during the low revs/idle phase. First point would be to test the battery terminals and then the charge rate.
 

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That light should not come on. Period. When it does you are being told the charge rate to the battery is low.

Check your battery cables and terminals, especially ground cable and attachment at the engine. Check connections from alternator to the battery/starter relay/main fuse.

It's intermittent, I would not suspect the alternator itself.
 

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Ok, so I check all the connections,the other and everything looked good. Buttoned it back up and away I went. So today I replaced the rear turn signals and front tire. But the bulb for the license plate light broke so I rode to get a new one. The battery light stayed on for the trip and was on on the way home. It had nevwr stayed on for that long beofre. I got the new bulb in and went to start it and nothing. Battery was dead. Hooked up a tender to it and let it charge for a bit and it started again but then the instrument cluster lit up everything, and flashed so I shut it down. Now when trying to start it the battery makes a fast clicking sound. So hooked my brothers battery to it and it fired right up, but the battery light remained on, and his volts dropped to 10 and we killed it. Does this just sound like a dead battery like I'm hoping it is, or something to do with the alternator? I hope it is nothing expensive or complex as this is my only means of transportation.
 

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Although your battery may now be shot (from repeated excessive discharge), your problem is not a bad battery.

Like with a car, one can start a bike with a bad battery with jumper cables, remove the cables and run it normally - as long as the alternator is charging correctly.

The ‘battery’ light is perhaps a bit of a misnomer, and should rather be called an ‘alternator’ or ‘charge’ light. It does not indicate the condition of the battery, but rather the condition of the current being generated by the alternator.
 

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Exactly the same conclusion I came to reluctantly. Gonna pull the alternator off tomorrow and hope I can find a replacement for it on a Sunday. I've read to take the tank off, then the starter, remove some wires, then I should have access to remove it. I was really fearing that it was the alternator, and I am not looking forward to it.
 

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Hi, when the light it's intermittent is a signal of coming bad alternator. So now is intermittent after few days or weeks will become fix light and yuor bike will not run or will stop (if battery it's totally died cause not recharged). First control how many volt is given the alternator and you'll understand if have some problem.
If you need an used alternator in good condition let me know
 

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Ok, so I check all the connections,the other and everything looked good. Buttoned it back up and away I went. So today I replaced the rear turn signals and front tire. But the bulb for the license plate light broke so I rode to get a new one. The battery light stayed on for the trip and was on on the way home. It had nevwr stayed on for that long beofre. I got the new bulb in and went to start it and nothing. Battery was dead. Hooked up a tender to it and let it charge for a bit and it started again but then the instrument cluster lit up everything, and flashed so I shut it down. Now when trying to start it the battery makes a fast clicking sound. So hooked my brothers battery to it and it fired right up, but the battery light remained on, and his volts dropped to 10 and we killed it. Does this just sound like a dead battery like I'm hoping it is, or something to do with the alternator? I hope it is nothing expensive or complex as this is my only means of transportation.
Ovvious it's an alternator problem
 

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Misty5, I'm thinking I'll end up having to get an alternator from a forum member. I'll let you know for sure once Ibget it out. Where are ypu located at? I am sure they are not cheap to ship. And you're more,than welcome to PM me a price if you've got one. Thanks.
 

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Okay folks, I am going to throw a booger in the pudding. There are several things that can cause a poor charge condition to show up. ONe of those things is a high resistive load in the circuit...i.e. a toasted battery. Another is poor connections at the star solenoid....which is a known problem with these bikes...yet another is poor grounds.

What I am saying here is to check your system before you go throwing the baby out with the bathwater. The alternator on these bikes is robust.

Yes, it could be a bad alternator, or more likely voltage regulator, but, without checking the simple things, you could just be burning good money.

Test your circuit. Check your connections.
 

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The first gen Brutale (and F4) uses a Denso alternator....just like those found on small cars !! It can be repaired by any auto electrical shop. Just kind of hard to get off and on the engine.

But as SilentService said, they rarely fail More often it is the charging connections going toward the battery. The "Charge Light" is simply saying voltage has dropped below normal. That is, charge voltage/amperage is not reaching the battery.

Japanese bikes (older Honda in particular) are famous for melting the 3 wire connector between the alternator output and the rectifier. Enough so that several companies offer repair kits for this connector.

On your MV, where the rectifier/regulator are enclosed in the alternator case, this connection is the one at the starter relay.

Your battery may recover if you charge it with a "Smart" charger. Discharge alone doesn't ruin a battery, sitting in a discharged state for any length of time does.
 

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Misty5, I'm thinking I'll end up having to get an alternator from a forum member. I'll let you know for sure once Ibget it out. Where are ypu located at? I am sure they are not cheap to ship. And you're more,than welcome to PM me a price if you've got one. Thanks.
Spedition cost is not expensive, i'm trying to send a pm but forum told me that you're not able to receive pm, send me your email and i'll send you photo and price, thanks
 

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Ive noticed when riding that every now and then my battery light on the instrument cluster will come on. It will stay on for a few minutes at most then go off. Normally this happens just after I've been at a traffic light for a decent amount of time. Is this anything to be worried about and should I be startibg to price an alternator, or is this something that happens with the first gen Brutale? Thanks guys.
I receved your message but i can't reply to you, you can't receive messages
 

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Discussion Starter #17
Fyi for the guys who have never had to pull an alternator on one of these, I hope you never have to. Such a pain in the @$$, gonna try to see about getting it repaired tomorrow from a shop where I live.
 

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So took the alternator to be rebuild by a local shop today, they hust called and said it runs great, just as good as a new one. I'm at a loss at the moment.
 

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So took the alternator to be rebuild by a local shop today, they hust called and said it runs great, just as good as a new one. I'm at a loss at the moment.
Only thing between the alternator and battery are wires and connectors....That is it. Period. No switches, relays or computers.
 

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So took the alternator to be rebuild by a local shop today, they hust called and said it runs great, just as good as a new one. I'm at a loss at the moment.
:wave:Geez, well knock me over with a feather!:shitfan:

Now that you have learned that one man's opinion, without basis or a diagnostic approach, is another man's wasted time and money.:stir:

Let's start over: First, please post the year and model of your B4 in your signature line. It will help us help you and we won't have to ask every time a post goes up.

You started this with an intermittent charge light at low RPM after a period of time at a standstill.

This indicates to me that your battery is a POS and probably should be replaced. However, you should load test that battery first. As a battery ages, its electrochemical potential decreases and eventually it is unable to be recharged. This is called depletion. If you start with a POS battery, depletion occurs more quickly.

If you get into your manual, for whatever year and model B4 you happen to have:ahhh:, you will find a troubleshooting guide that is very efficient and determining the trouble. If you choose not use a written scientific methodology, then I would first check the battery status, then I would check the connections at the start solenoid (behind the battery under your seat) and by "check" I mean: Remove the connections, clean the connections, apply a quality electrical grease, and then reconnect paying particular attention to polarity.:nerd:

While you have the bike apart, clean the ground connection at the engine and the connection at the alternator. Were I you at this stage, I would opt for a set of low oxygen cables of a bigger gage and replace what is there on your bike. I mean, it's already apart...and, IF I knew what yer and model your B4 was, I could probably offer you a set that I have here at a discount; but, alas.:ahhh:

Your alternator does not even begin to charge your system, according to the manual, until RPM is at or above 5000. Think that through.:confused::idea:

I do recommend that you approach this differently from the recent past. Buying an alternator that you don't need from @misty5 is a foolish way to go about fixing a problem.:smoking:
 
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