MV Agusta Forum banner

1 - 20 of 20 Posts

·
Registered
Joined
·
87 Posts
Discussion Starter #1 (Edited)
Hello all.

Not to repeat my self with posts this is starting from the beginning and working out where did i go wrong on fixing this problem.

I started with the following questions in regards to the bike.

1. problem was that i had a discharging battery. The problem was the battery not having power to turn over the engine from a week of sitting around and not running.

2. The bike would run after kicking it over by dropping a gear or jumping it with another car or charging the battery over a tender.

3. After deciding on replacing the battery with a lithium 12 cell the bike started up like a charm. After taking it for a spin the battery light started flashing and then went fully red. After a bit more riding the power started to fade away from my lights speedometer and RPM gauge. Then it just fully shot down and came to a halt.

4. After that happened i changed my 12 cell lithium to my old acid battery and tried on jumping it. After jumping the battery the bike started up but then after i pulled the jumper it died.

5. I checked the fuses next to the battery and found out that one of em was blown so i changed the number 40 fuse for a new one. The battery had no power to turn it over so i tried to see if i could jump it once more it did not work. So i tried a rolling start it turned on for a split second and then died

6. I talked to a tech near my work that do some MV repairs but not electrical work. He told me that starters and alternators dont usually go out of work on bikes. He told me to look into a Voltage regulator
I have no idea where to look for that... i went over all the shop drawings for the bike including the owners manual and could not find anything to do with the voltage regulator.


Now my question can it be something with the SPU, Voltage regulator, or alternator.

Whats the best way to test this problem at this point and time.


I do have a problem with my low beam light as well in regards of it night working. I checked fuse and connections changed the bulb 2 times and no luck.


I dont know any more. In regards on taking it to the shop i wold love to but its a good 50 mils away so i would like to see if i can find the problem before i relocate it to a licensed MV Agusta Dealer/shop.

Thanks guys

once again sorry for re-posting and re Threading. I hope this just gives more of the back story about all the problems.
:lightning

and do you guys know of a good place to order parts from.
 
  • Like
Reactions: TheTallBela

·
Registered
Joined
·
13,695 Posts
It sounds like you have multiple issues. Alternator not charging, spu gone or going bad.

I would take the time, drive the 50 miles and bring it to the shop. Unless you are fully competent with motorcycle electronics, it is likely you'll tear your hair out and spend hundreds of dollars swapping parts before you find the problem.

Bring it to someone who can work on the bike, diagnose the problem, and fix it.
 

·
Registered
Joined
·
87 Posts
Discussion Starter #4
Did you check if you connected the battery the right way round. Post some pictures. If you blew the 40A fuse, I'm wondering.
i have a black from under the gas tank connected to the negative and for the positive i have the red top cable and the small black one that is attached to the positive that is connected to the positive runs back to the negative.

same way it is shown in the manual. 2 to the negative and one to the positive. i will attache pictures later on tonight
 

·
Registered
Joined
·
13,695 Posts
I think what Donsy is asking is did you connect the battery backwards and fry the diode. That frequently happens.

The black wire going under the tank from the negative post on the battery goes to ground. There is a large black wire from the wire harness connected to the negative post on the battery. The second wire from the wire harness connects to the positive. Another wire goes from the positive to the starter solenoid.

So, you should have two wires on the negative post and two wires on the positive post. Plus, battery charger if you have one.
 

·
Registered
Joined
·
14,532 Posts
woes?

Carl & Donsy;
he did the 40Amp fuse in and probably the diode too

it had to have been connected wrong

then it eats a 12 cell LiPo and he gets the red light

Donsy how long can you run total loss on a LiPo 12 cell?
 

·
Super Moderator
Joined
·
22,072 Posts
Carl & Donsy;
he did the 40Amp fuse in and probably the diode too

it had to have been connected wrong

then it eats a 12 cell LiPo and he gets the red light

Donsy how long can you run total loss on a LiPo 12 cell?
At full blast, not more than 22min, no lights etc.
I see where this is going :).
Do the Brutale's have diode's like the F4 Noel/Carl ?
 

·
Registered
Joined
·
87 Posts
Discussion Starter #8 (Edited)
At full blast, not more than 22min, no lights etc.
I see where this is going :).
Do the Brutale's have diode's like the F4 Noel/Carl ?
I have the 2005 750f4 brutale
hmmm so now if its the diode how do i fix that and where can i buy the part.?
 

·
Registered
Joined
·
13,695 Posts
I don't think the Brutales in '05 have a diode. Or if they do, it's not where it is on the F4.
 

·
Registered
Joined
·
87 Posts
Discussion Starter #11 (Edited)


as you can see i have 2 black ground and one main one that links the one from 40 fuse to the main power cable at the +

now from reading in regards to diode burning out something in regards to the fuel pump not working this is just digging into a deeper hole
 

·
Registered
Joined
·
87 Posts
Discussion Starter #12
Paradox at work.

I just got a call back from the shop after running a full diagnostic sweep threw the electronics inside the bike from the CPU to the alternator to the starter and back again threw everything for the final inspection before giving me a good to go and a green light on picking up the bike today or tomorrow.

I am happy non the less. just a little bit shocked and surprised in regards to what was really going on with the electrical all this time.

Maybe everything was good and all it was a 40amp fuse that burned out during the ride and killed of the alternator to feed the energy back to the battery!
 

·
Registered
Joined
·
9,955 Posts
I don't think the Brutales in '05 have a diode. Or if they do, it's not where it is on the F4.

I think I remember reading in the past that this is inside the SPU on these bikes...

Be good to see a wiring diagram for this bike to confirm one way or the other..
 

·
Registered
Joined
·
9 Posts
Hello all.

Not to repeat my self with posts this is starting from the beginning and working out where did i go wrong on fixing this problem.

I started with the following questions in regards to the bike.

1. problem was that i had a discharging battery. The problem was the battery not having power to turn over the engine from a week of sitting around and not running.

2. The bike would run after kicking it over by dropping a gear or jumping it with another car or charging the battery over a tender.

3. After deciding on replacing the battery with a lithium 12 cell the bike started up like a charm. After taking it for a spin the battery light started flashing and then went fully red. After a bit more riding the power started to fade away from my lights speedometer and RPM gauge. Then it just fully shot down and came to a halt.

4. After that happened i changed my 12 cell lithium to my old acid battery and tried on jumping it. After jumping the battery the bike started up but then after i pulled the jumper it died.

5. I checked the fuses next to the battery and found out that one of em was blown so i changed the number 40 fuse for a new one. The battery had no power to turn it over so i tried to see if i could jump it once more it did not work. So i tried a rolling start it turned on for a split second and then died

6. I talked to a tech near my work that do some MV repairs but not electrical work. He told me that starters and alternators dont usually go out of work on bikes. He told me to look into a Voltage regulator
I have no idea where to look for that... i went over all the shop drawings for the bike including the owners manual and could not find anything to do with the voltage regulator.


Now my question can it be something with the SPU, Voltage regulator, or alternator.

Whats the best way to test this problem at this point and time.


I do have a problem with my low beam light as well in regards of it night working. I checked fuse and connections changed the bulb 2 times and no luck.


I dont know any more. In regards on taking it to the shop i wold love to but its a good 50 mils away so i would like to see if i can find the problem before i relocate it to a licensed MV Agusta Dealer/shop.

Thanks guys

once again sorry for re-posting and re Threading. I hope this just gives more of the back story about all the problems.
:lightning

and do you guys know of a good place to order parts from.
I’m having the same issue. Something is draining my battery. Also my fuse next to the battery one was blown out and I changed it. However also the way that fuse goes in seems lose. Meaning it doesn’t really Clip in tight. So I was recommended to put a small piece of tin foil or to pry it tight a little. I need to figure or what is draining my battery. Can it be because the fuse is not fitting well?
 

·
Super Moderator
Joined
·
22,447 Posts
The fuse next to the battery fuse is a spare and does not fit in its holder tightly. That is why there is a clear cover for it.
That would indicate that someone has used that spare fuse.

What is the year and model of your bike?
 

·
Administrator
Joined
·
20,019 Posts
A loose fuse will not cause battery drain. It will result in heat related melting of the fuse holder due to excessive resistance....and it could result in intermittent blown fuse....but something else is draining the battery.

Have you confirmed a high key off current draw (>10mA)?
The meter is always drawing a bit of current from the battery, but it in the order of <10 mA...and won't kill a battery overnight.
 

·
Registered
Joined
·
14,532 Posts
Annabel;
Can you get the bike started? Measure the voltage across the battery terminals
with the bike running and report back
Remove all the fuses except the main fuse
Key off, connect an Amp meter in the battery circuit.....
Install the fuses one by one......watch the meter
One fuse will show the discharge
 

·
Registered
Joined
·
101 Posts
I have come across this problem SEVERAL times playing with Lithium batteries. I can tell you exactly what happened! There was nothing wrong with the bike other than a dead battery. The 40A fuse burns out when it works too hard trying to charge a dead battery. There's nothing regulating the AMPERAGE on the charge circuit. So, if a dead battery is willing to accept a 50A charge rate, the alternator will give it 50A. Of course, that blows the fuse because it's only 40A. Then you get no charging at all.

In step 2, you got the bike running. The alternator tries to charge the battery, but the current is too much for the fuse to handle and burns out. The battery had just enough juice to run the engine a short bit. Step 3, you replaced the the battery with a Lithium battery. With a fresh charge, the lithium battery starts fine and runs for a while until it's dead. It's not getting a charge because the 40A fuse is blown. You fixed the problem in step 5 by replacing the fuse, but you need to charge the battery before trying to run it. Otherwise, the fuse will blow again as soon as the alternator tries to charge the battery.

Do yourself a favor...
1) Buy an auto-resetting 40A fuse. You'll probably only find them online. I was only able to find 30A in local auto parts stores.
2) If you're in the habit of draining your battery, get rid of the Lithium battery. I SO wanted to keep mine because it's so lightweight and gave great cranking amps, but there are several problems. A lead acid battery will be weak cranking the starter. So, you know it's low on cranking amps. Lithium batteries will give you no warning when they go out. A Lithium battery will give its all and crank like new in the morning. You make a stop for breakfast and it won't start. When it wants to give out, it's very sudden. It has happened to me at least 3 times. The only way I would keep a Lithium battery is if I always remembered to keep it on a float charger.
 
1 - 20 of 20 Posts
Top