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Discussion Starter · #1 ·
Just back from a trip around East Cape. Bike went well, until just about home, it seemed to lose power for a moment. A warning came up underneath ABS Normal saying Malfunction. Pulled over to the side of the road and as I was slowing it came up with STOP, FAULT, Exhaust valve.

Stopped, restarted, all OK, carried on to home, then same again. Malfunction when riding, as you slow it goes to Fault, exhaust valve. Checked while revving it and you can see one of the exhaust valve cables move above 4,000 rpm.

I have around 500 kms to go before the 6,000 km service, and spoke to the dealer. He said it won't cause any harm to keep riding it. Said maybe a stone in the cable pulley or cable needs adjusting?

I had the bike down to Motorad on Wednesday last week for it's 6,000 km service, and to get them to investigate the exhaust valve fault.

Took the bike out for a ride on Saturday and the same thing happened. First 40 kms from home was OK, stopped at the pub, then half way home malfunction, fault, exhaust valve was displayed.

Happened on Sunday ride, and Tuesday after work ride as well.

What does this valve do, and can it be disabled without affecting the warranty?

Spoke to dealer again, he said he had adjusted the cables on the exhaust valve.

Further to this, while out riding on Saturday, it came up again, about 80 kms into a 100 km ride.

This time it lost power and would not rev out, we were going very quick, and coming out of a corner the exhaust note changed and it was like the engine was being strangled, it was not the rev limiter kicking in.
Did a km or so, then pulled over.

Once stopped, the malfunction warning changed to fault, exhaust valve. Turned off for a few minutes, then restarted and continued to the destination with no issues' and full power.

Warning came up again, but no loss of power on return ride home.

Was out again yesterday, and same thing happened, warning up on screen, about 30 kms down the road, lost power, would not rev, and very muted sound from engine.

Stopped and cut engine, restarted, all ok for the rest of the ride, warning, malfunction came up slowing as I came into 50 km area before home. Parked in driveway at home, and stop, exhaust valve came up on display.
 

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Mate i dont know but if it was me i would have stopped riding the bike the first fault came on. That is a standard fault in the new mVs. You need to take it back to the dealer theres i think a sensor that has failed. Needs replacing. There are many more threads on the same issue do a search.
 

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Discussion Starter · #4 ·
Both the dealer and the technical/warranty manager for the importer said it won't do any harm to keep riding it, I hope they know what they are doing? I'm thinking sensor too, it feels like the valve is closing briefly while riding. I have searched threads for similar, can only find F3 800.
 

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The exhaust valve is a flap inside the exhaust pipe under the engine that closes at low rpm, to increase exhaust back pressure. It is spring loaded to be normally open. You should be able to locate a pulley on the exhaust that has 2 cables coming from it that go back to an electric servo motor located under the tank.
It would seem that the flapper is sometimes sticking closed, which is strangling the motor at high rpm.
Each time you turn the key on, the ecu cycles the valve from full open to full closed as part of the engine check. This calibrates the system, so if there is a change in the flap movement limits during operation, it throws an error light, and stores an error record in the memory.
Given that this seems intermittent, I would suggest going through all the related electrical connections with dielectric grease.
 

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Discussion Starter · #6 ·
There seems to be 2 schools of thought about what the valve does. On the Ducati 1199 Panigale/ Multistrada they say it is there for noise reduction to pass the European emissions test.
The MV dealer's mechanic agrees with this in relation to the exhaust valve on the MV's. I was told today that if the valve is disabled, then it would void the warranty.
Some say it there to give torque at lower revs. I'm no mechanic, but I
can understand the theory.
 

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Chris, his bike is a 2014, it was made in China, hence the spelling.:jsm:

To the OP. Do some research. There is plenty of discussion on Exhaust Valves and what they may or may not do; however, if that valve closes while you are riding, it is like putting a potato in your exhaust, or, in your case, four small red potatoes.

The ECU controls the valve actuation. If it is malfunctioning, have the dealer fix it.
 

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Not on mine. Disconnect the cables and it stays open. It is spring loaded. I would be surprised if the models are different.
 

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It is normally open. Think about it.
 

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they are for noise......

like the flapper in my '04 Aprilia RSVR's intake.....

doubt me??

pull the top off an Aprilia's air box and start it......:wtf::wtf::wtf:

WARNING wear ear plugs AND HEARING PROTECTORS


it's that loud


:popcorn:
 

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Discussion Starter · #12 ·
Does anyone with a late model F4 know, when the valve opens and closes? I have been told that the valve should open and close/ or close and open, during the system check procedure when you first turn on the ignition.
I turn the key and nothing happens down below where the valve is located, but it sounds like a servo motor turning under the tank? I have tried to turn the valve with a spanner, but it does not move.
Could someone turn the ignition key on and look to see if their valve moves during the pre start cycle, it would be much appreciated, and possibly a starting point to let my dealer know. Thanks.
 

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I don't understand this discussion. The bike is still under warranty isn't it? Tell the dealer to behave professionally and get the knowledge to fix the thing.
The flapper is opening gradually, that's why it is operated by a servo motor instead of a solenoid which is either full open or full shut. Unless you have access to the ecu, there is little way of knowing the conditions when it operates. Suffice to say that at idle and low revs and in neutral where the dreaded red tape police measure for legality, it is less than fully open.
It's quite simple. Pull the tank and watch the servo and top pulley with the cables disconnected. If they move, good. With the cables disconnected, try to turn the flapper. If it moves manually, good. Check the cables aren't seized. That covers the mechanical possibilities.
Now on to the electronic possibilities if the above doesn't come up with a fault. Check the connections are solid. Vibration can cause an intermittent issue. Grease them with dielectric grease while you are in there.
After that we are into the realms of deeper analysis, which will require access to software.
Hope this adds some sanity to the thread...
 

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I agree that this bike should go back to the dealer for repair under warranty.

I also think that GrantNZ should download the manual form Donsy's site and read the section on operation and testing of the exhaust valve.
 

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Discussion Starter · #16 ·
It has been back to the dealer 3 times, with no answers, that is why I am asking here.

We only have 4 dealers in our country, the closest is a 4.5 hour drive away. The next is 9 hours away.

I am reluctant to give the bike to the dealer again and wait for them to sort it, without them having some idea as to how they are going to fix it.

Maybe time for a road trip to another dealer.
 

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I would leave the servo in place and electronically connected. Then, I would disconnect the valve control cables disabling the valve open.
 

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Maybe time for a road trip to another dealer.
Apologies for being direct.
It must be really frustrating when you are dealing with untrained techs who can't seem to even do the basic troubleshooting.

In Australia, if we start fiddling around with things ourselves, it can void warranty. Proceed with caution.

I would suggest escalating the issue with someone further up the chain of command, until you get a satisfactory result. On what you have laid out in your original post, it should be a simple fix.
 

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It is closed at idle and begins to open as the RPMs rise on the 14 model. apparently yours is not actuating properly during running. They need to troubleshoot that. could be the actuator or servo for that no? or something else, either way they need to clear that darn problem IMO, good luck.
When I had to reinstall my Corse exhaust, I learned about the cables, detatched and reattached them to the mechanical valve on the exhaust. Mine works flawless but I lubricated the mechanism with grease and the cables as well, knowing that this area will attract dirt over time.
 

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Discussion Starter · #20 ·
Thank you Fragile. I removed the heat shield and noted the position of the valve. The top cable is tight, the lower cable is loose. Then I started the bike ( the valve does not cycle or move when the key is turned on). The valve is moving when idling, only a little, then as revs increase the valve appears to open and close when revving the engine. All good so far. I took it for a ride yesterday, and after around 50 kms (30 miles) the warning came up. As we slowed coming into town, I could hear the valve was open by the extra noise it was making. I parked the bike with the motor running, and noted that both cables are tight, the valve is midway between the stops, and does not move when revving the motor. I stopped the motor and then restarted it, the valve did not move at all even when revving. We had 2 more stops during the ride and the valve was in the same place, half open, and not moving. I checked it this morning and the valve is in the fully closed position. So I am guessing the valve is sticking when hot? The dealer's tech rides the bike around a 2 km block at 50 kms an hour during the test ride, and of course, everything is OK.
 
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