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Discussion Starter #1 (Edited)
Hi everyone! a once very happy owner of a Brutale 800 here that has 12000 kms on the clock with no serious issues (gear indicator isnt accurate but no biggie) till about 5 weeks ago .

The bike just refused to start and has been stuck in the shop for a month. I desperately need some advice from the good people on this forum! ..Here are the details

When Clutching in and hitting the starter button u hear the starter spin up but bike doesn't start.

1.) At 1st I believed it was the starter/sprag clutch ( one way bearing ) problem but the mechanic that has been working on the bike says there is compression and the crank is spinning. This should mean the starter motor is turning the engine.

2.) Plugging in and Running the diagnostic tool shows no error message

3.) After a lot of testing the mechanics found that the spark plugs do not fire during the starting sequence .

4.) the 1st assumption was a faulty rpm/crank sensor , but after replacing that the bike still doesn't fire up

5.) The only piece left seems to be the ECU or the pulser/timing* coils but the mechanic cant seem to find that component .

Really hope someone out there can help me. I've never been so sad about a bike before because it feels like there no hope in sight to get this beautiful machine running again ..

really feels soo horrible just watching it sit there and i cant ride it. anyway here are some pics of when the bike was running and the bike in the shop !



*The Pulser Coil, (often called Pickup Coil, or Timing Coil) is responsible for providing the timing signal to the ignition control box on modern motorcycles with solid-state ignition systems.
The CDI box is fed timing data from the Pulser Coil, which produces a short duration, low current, high voltage pulse in relation to the Top Dead Center (TDC) piston location in the engine.
courtesy of this link http://racetechelectric.com/ft-752-pulser-coil-ignition-systems.html
 

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he can't find the coils? what does that mean? aren't they sitting right on top of the plugs? they are red.....

doesn't sound too hard to fix, the issue will be getting replacement parts from Italy especially during the summer.
 

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A coil is attached to each plug. Upper Left device in this image.

Your mechanic should know this and I would seriously consider changing mechanics if yours is just winging it.


View attachment B3 Motor Image.pdf
 

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Discussion Starter #4
he can't find the coils? what does that mean? aren't they sitting right on top of the plugs? they are red.....

doesn't sound too hard to fix, the issue will be getting replacement parts from Italy especially during the summer.
Hey there Higgs !

my apologies you are definately right the ignition coils are right on top in red and black ..i should edit my post to say only " Pulser Coil "

"Pulsar coil,often called Pickup Coil, or Timing Coil. This component is responsible for providing the timing signal to the ignition control box on modern motorcycles with solid-state ignition systems. "

I believe this is what the mechanic said he was looking for that the modern MV may not have. As a failure in it may cause the this lack of spark firing .
 

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You're from Singapore? Saw that IU unit...
Anywhere which workshop you send to? As I know that Xtreme machine should be the dealer and they authorized Ram Racing to be their workshop. They should able to fix your problem.
 

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Discussion Starter #6
A coil is attached to each plug. Upper Left device in this image.

Your mechanic should know this and I would seriously consider changing mechanics if yours is just winging it.


View attachment 160666
Hey Silen, Thank you so much for the exploded diagram of the B3's ignition systems ! Ive been trying to find the B3 parts manual online any chance u can direct me to it would really appreciate it =)

Anyway yes you guys are right about the ignition coils they are there plugged into the cam cover as they shud be , as i replied higgs the mech was refering to the pulsar/timing coils, apologies my mistake !

Btw I'm not sure if the brutale 800 has a pulsar coil or how it reads the timing and relays that to the ECU. It may have some other system.

Btw I understand the basics of motorcycles and do simple hands on work but thats about it so forgive me if i get anything wrong .

In regards to the shop , Its the dealership i bought the bike from so warranty issues have to go through them. but besides that they have had years of experience dealing with Mv Agusta s . its just that this 3 cyclinder platform is very new to them .


Again thank you for the replies .. i really dont want to give up on this machine over what should be a simple issue.
 

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Discussion Starter #9
Shin, this link exists at the top of each maintenance section. Donsy has been compiling manuals here.

http://www.mvagusta.net/forum/showthread.php?t=105793

Oh man , sorry again Silent , I just got home form the shop thinking the bike would finally be fixed so im a lil all over the place :ahhh:

I should have checked this maintenance and tech issues forum , I even posted my thread in the wrong forum .. this noob apologies!!!
 

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No worries. Hopefully you will be sorted soon.
 

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Shin, my mechanic had a similar problem with my B3, he checked the starter Sprag clutch, thought it was ok. Continued to check the bike over could find no reason for non start.

He had a new replacement sprag sat on the bench waiting for another B3, tried the new one in mine, bingo started right up, he said the old one was turning the engine but just slipping a bit and could not get the crank to spin up enough to kick it into life. He learnt a new one there. Even keeps a new sprag in the shop now because it is the source of many problems on this model.

So ask the shop to get a new sprag part in and stop tearing your bike apart. It worked for me.

jimboF4
 

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Discussion Starter #12
Hey Jimbo,

Seriously appreciate the advice man ,heck I will show the mechanic your reply.
I had a feeling that the issue was either due to some weird wiring sensor nonsense or the sprag clutch but it was hard to argue when they're sure the crank was still spinning and the engine still had compression

Now i just hope they get it settled as fast as they can!!


Shin, my mechanic had a similar problem with my B3, he checked the starter Sprag clutch, thought it was ok. Continued to check the bike over could find no reason for non start.

He had a new replacement sprag sat on the bench waiting for another B3, tried the new one in mine, bingo started right up, he said the old one was turning the engine but just slipping a bit and could not get the crank to spin up enough to kick it into life. He learnt a new one there. Even keeps a new sprag in the shop now because it is the source of many problems on this model.

So ask the shop to get a new sprag part in and stop tearing your bike apart. It worked for me.

jimboF4
 

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Discussion Starter #14
Starter sprag will fix you right up. it's an easy process too, won't take more then one day.
Hola Gonzo! man you have no idea how many times i've rewatched your QD exhaust fly by videos on youtube this past month just to get a lil fix since my bike is in the shop hehe :cry:! Anyway yeah I really hope that's all there is to it though it'll take a while for the sprag to fly in my lil island.

honestly if it wasn't for Jimbof4's reply I still wouldn't have thought the sprag clutch to be an issue, since thumbing the starter still cause the crank to turn and......i assumed if the sprag/starter clutch died , there would be no turning what so ever !O_O

That the crank turned and there was compression in the cyclinders threw me and the mechanics off from the sprag making us rightly assume its an electrical issue.
Specially since they checked that no spark ignited aswell!

Once again many many thanks to all especially Jimbo! and also silentservice and donsy for directing me to the collection of manuals.
I've show the mechanics the post and the used the printed out manuals to explain and they were very very receptive because it was driving them crazy tearing the bike apart trying to figure the issue , all sensors , fuses, fuel lines spark plugs were fine ! they had one hell of a head ache

I will keep this thread updated .. specially if the bike gets running again, and then bloody hell ill treat it to a onlins ttx rear shock !
 

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ah... I'm sure your mechanic has already done this however, it is a well documented problem that the OEM Koyo batteries that came with the bikes (I'm not sure if MV have changed suppliers yet or not) won't hold a full charge. My mechanic informed me that the battery must produce at least 12.5 volts to fire the plugs. It'll spin the engine over on less voltage but it will not start.
 

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Discussion Starter #16
Hi Stephen, thanks for that tidbit . Im not sure if they changed suppliers but for as long as ive noticed the bike always had a yuasa battery, a YTZ10S model if not mistaken. The mechs did test that battery and i was told it pretty healthy.

ah... I'm sure your mechanic has already done this however, it is a well documented problem that the OEM Koyo batteries that came with the bikes (I'm not sure if MV have changed suppliers yet or not) won't hold a full charge. My mechanic informed me that the battery must produce at least 12.5 volts to fire the plugs. It'll spin the engine over on less voltage but it will not start.
 

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On the battery issue, yes early bikes had some rubbish batteries fitted, I changed mine to Yuasa YTZ10S as Shin has fitted, despite having done this the starter sprag clutch was the issue, not lack of cranking amps to the starter motor.

jimboF4
 

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I wonder, based on the away a Sprag Clutch works, if the mechanism is weak in the starting direction could it drag in the running direction?
 

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Discussion Starter #19
Hey Silentservice, so far my experience which is about 12,000km or 7500miles on this brutale 800 , Ive have had no issues with the bike stalling. I have stalled it when doing slow speed maneuvers while dargging the rear brake and slipping the clutch because its not as easy to gauge throttle response with the ride by wire system. Besides that no stalling ...

However my experience was that it got harder and harder to start the bike over time ..it would crank for a bit and then let out a metallic "klatunk!" sound.

I remember reading somewhere to pull as little of the clutch lever as possible to engage the switch so that the drag from the clutch and transmission somehow helping the sprag to engage and it worked for a decently long time.

so thinking about it that way, maybe a truly faulty sprag clutch could cause drag from the crank direction
I am assuming with enough of those" Klatunk " sounds the little bits of the sprag clutch that engage the gears that go to the crank but let go when the crank starts spinning could dislodge themselves ...and cause that drag maybe?
 

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