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Discussion Starter #1
Hi there,

im having some issues with my bike.. let me start from when i think the problem started.

When riding, sometimes one of the bikes cylinders would stop firing for about 5-10 seconds, and then itl start working again. That was it... this would happen once a week.

THEN. after about a month, the same thing happens but much more often, but itl only be off for a split second. but itl happen like 20 times off and on as im riding. (one cylinder goes off and on rapidly) i can feel the power drop and rise on the bike.. this is hard for me to explain clearly, but this is the best i can do..

and this continued on for about a week, then one day when im going into work, two of the cylinders completely went off. didnt come back on, and the bike lost a huge amount of power, the exhaust sounded like a normal 1 cylinder bike. and i pulled over, switched ignition off. let it cool a bit, then tried it again.. nothing, the bike turns over, with only 1 cylinder trying to ignite, but the bike doesnt catch on. it just stalls immediately.

i got it home, fully charged the bike, and still same thing but this time, no ignition at all. all that happens is the engine turns over endlesely.

I have NO idea what is going on, but i would appreciate any help.

(one thing to note, my fron ABS sensor wire was snipped off by a jealous twat while the bike was parked, but this happened months ago and well before these issues came up)

Thank you,

Ersan.
 

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Is the bike still under warranty? If yes, then its the dealers problem.

If not and you want to try fix it yourself, take off the tank and check your coils going to the plugs and wiring down there. Maybe something came loose or rubbed.

Also check your fuses.
 

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ABS has nothing to do with this...it does sound like a wiring fault that has been developing over time... Like PTsalas said, take off the tank and start inspecting the wiring harness/connectors. Would also look at areas around the steering head where the harness bends when steering..
 
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Hello. Something like this happened to my 2015 V7 Racer Motoguzzi.
This happened in the first 250km with my V7( new bike). The wiring coils were too long, and one of the wires touched the cilinder, until it melted. So, one of the coils stopped working for a short circuit between the wire and the cilinder. I lost almost all the power because just one cilinder were working. If that is the case, it can be fixed by replacing that wire. My advice, is if you still have warranty, use it. And if not, you can look for the problem by removing the fuel tank.

One question: what do you mean by "fully charged the bike"?
 

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Discussion Starter #5 (Edited)
update,

i have removed the fuel tank, and checked the wires and HT leads and coils. the plugs are all dry as a bone. and looking good. There was fuel coming out of the fuel lines leading into the injectors, so fuel is going to the plugs?

How can i test the coils for spark? i tried the old method of plugging a spark plug on the coil and touching it on a ground point on the bike while pressing the ignition. but no spark to be seen. but then again since everything is off, the dash is giving me sensor errors etc so im wondering if thats causing it to not spark as a fail safe?

im so frustrated, not a clue what happened and i have NO Idea what to do.

sadly, i do not have a valid warranty, it was a second hand bike.
 

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update,

i have removed the fuel tank, and checked the wires and HT leads and coils. the plugs are all dry as a bone. and looking good. There was fuel coming out of the fuel lines leading into the injectors, so fuel is going to the plugs?

How can i test the coils for spark? i tried the old method of plugging a spark plug on the coil and touching it on a ground point on the bike while pressing the ignition. but no spark to be seen. but then again since everything is off, the dash is giving me sensor errors etc so im wondering if thats causing it to not spark as a fail safe?

im so frustrated, not a clue what happened and i have NO Idea what to do.

sadly, i do not have a valid warranty, it was a second hand bike.
I dont know the process to test the coils off the top of my head, but will direct you to where you can download the service books (free downloads).

The shop manuals have the procedure to test the electrical and coils. You can download there:


Take note, there are 2 service books, one for the chassis and one for the engine. The test for coils could be in either so download both.
 

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Discussion Starter #7
I dont know the process to test the coils off the top of my head, but will direct you to where you can download the service books (free downloads).

The shop manuals have the procedure to test the electrical and coils. You can download there:


Take note, there are 2 service books, one for the chassis and one for the engine. The test for coils could be in either so download both.
I found the procedure to test the coils but it involves taking the coils out which the cables seem to be deep inside the frame, i just wanted a simpler ground spark test to be done, but looks like modern bikes donw allow for such thing.

i will be removing all the stuff i need to in order to get the coils out then i will test for impedence as per the manuals, though it feels like its something else that is causing the issues.
 

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You can test your coils the good old fashioned way, by sticking a spark plug in the coil, grounding the plug and hitting the starter. Spark? they're good.
Nothing special or different from any vehicle ignition.
You know, it could be injectors (fuel) and not spark that is causing your power loss.
Failed coils will give a "check engine" malfunction indicator lamp on the dash and a code. So will a failed injector.
Follow the troubleshooting steps in the manual.

If you are not seeing a fault on the dash it could be fuel supply. Did you get some crap gas? Has your fuel filter become plugged up?
 

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Discussion Starter #9 (Edited)
You can test your coils the good old fashioned way, by sticking a spark plug in the coil, grounding the plug and hitting the starter. Spark? they're good.
Nothing special or different from any vehicle ignition.
You know, it could be injectors (fuel) and not spark that is causing your power loss.
Failed coils will give a "check engine" malfunction indicator lamp on the dash and a code. So will a failed injector.
Follow the troubleshooting steps in the manual.

If you are not seeing a fault on the dash it could be fuel supply. Did you get some crap gas? Has your fuel filter become plugged up?

I checked all the coils and none of them are sparking even after connecting all of the sensor except the ABS one since it was vandalised. Oh also there is a phase sensor error as well. But I'm sure that was there before... I cant recall.

any suggestiong what i need to look at next?

thanks
 

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I checked all the coils and none of them are sparking even after connecting all of the sensor except the ABS one since it was vandalised. Oh also there is a phase sensor error as well. But I'm sure that was there before... I cant recall.

any suggestiong what i need to look at next?

thanks
Yes, check the fuses, should be a quick check. Phase sensor error was related to sprag clutch failures and possible low battery.
 

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Discussion Starter #11
Yes the fuses.
I checked all the fuses on the little box at the side of the bike, and they are all perfectly intact. I also checked the ignition fuses the 30A ones. And they are also in good condition with no breakage.

Are there any more fuses? I looked all over the bike. Couldn't find anything else.

Thank you.
 

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Discussion Starter #13
Check the voltage on your battery
Battery is fully charged over night. I am using a lithium iron battery with its proper charger. It was charged over night. And the voltage was just under 14v. The battery is also brand new. Less than 2 months in use.
 

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Only thing I could think of is battery as that would also explain the phase sensor error. Hoping someone else can assist you.
 

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Phase sensor is the crank position, or rpm sensor. This input is required for the ECU to know when to fire a coil or injector. If you are getting this error code while engine is spinning quickly with a fresh battery then that sensor may be faulty. It can be tested. Insulation, resistance and peak voltage.
 
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Discussion Starter #16
Phase sensor is the crank position, or rpm sensor. This input is required for the ECU to know when to fire a coil or injector. If you are getting this error code while engine is spinning quickly with a fresh battery then that sensor may be faulty. It can be tested. Insulation, resistance and peak voltage.
Is the Engine Pick-up the same thing as the phase sensor?

also if i want to check the timing wheel gap, do i have to drain the oil out? or would i be safe with the oil still in the engine?

thanks.
 

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Yes...engine pick-up would be another name....the one that senses the phonic wheel rotation. I think it can be checked without draining oil.
 
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Discussion Starter #18
Yes...engine pick-up would be another name....the one that senses the phonic wheel rotation. I think it can be checked without draining oil.
I have checked the Phase sensor impedance and its coming at 666 Ohms +/- 2 ohms. so that is within spec isnt it?

i have checked the gap between the pick-up and the timing wheel and its way below spec. the feeler gauge struggles to go in at 0.4mm at 0.5 it will not go in between the sensor and the wheel.

how can i adjust this? is it important to get 0.6mm? would 0.4mm cause phase error?

thank you.
 

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Discussion Starter #19 (Edited)
I took each coil out, i see that they are numbered which i did not know. Anyway... i went to test them as per the manual and the impedence between the high voltage positive and the pole number 2 of the connector is all within spec at 3.84 KOhms.. HOWEVER.... when the manual also says to check the impedence between the pole number 1 and 2 of each coil.... i get ZERO... but the manual says it should be 1 Ohm... now not sure what to do...
 

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How good is your ohmmeter?? Zero is damn close to 1 ohm and a cheapo meter may not show it. I don't think it is your coils.

What about insulation to ground on the crank position/rpm/phase sensor? It must be infinite on a high resistance scale

Too small an air gap on the sensor is usually not a problem, too big is. But you could add an o-ring to space it out as a trial.

Do you have the Engine and Chassis Workshop Manuals?
 
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