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Discussion Starter #1 (Edited)
So I just had my spark plugs replaced because I thought maybe that's why it has been running awful. I also swapped the coils with some used ones while I was at it even though I didn't think that was the problem. Well, went for a ride and nothing has changed.

It seems related to heat. It will run fine when cold. Then it runs worse and worse as it gets hotter. If I hit an open stretch of road then it may cool down and run better. But sit in traffic long at all and it will get worse until it finally won't start at all.

I should mention it starts as a rough idle. Then it gets to where it won't idle but will still smooth out as rpm's increase. Then rougher and rougher.

I made a gopro video of me driving it home from work. I think you will be able to tell what I mean from the video. Keep in mind that the evening air is pretty cool - it would have got worse in a hurry if the outside temp was warmer. Also, I was driving pretty aggressively to keep moving - I don't usually drive like this. If I had stopped for traffic I never would have made it home.

Video coming up in a little while after I upload it to youtube...

Long, boring video: http://youtu.be/W1M2t3jpQEY

Also, the bike was not cooled off when I started. It had been run less than an hour before. Would have run better at first if it was cold.
 

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A far out guess would be if you ran any leaded gas and cooked the oxygen sensor.
 

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Discussion Starter #3
A far out guess would be if you ran any leaded gas and cooked the oxygen sensor.
Oops, forgot to mention the bike has a full Arrow exhaust and race ecu - I got it that way from the previous seller (with 1500 miles on it). It has run perfect until rather recently (now has just over 12,000 miles on it).

I'm thinking because of the modifications that it no longer has an oxygen sensor. Is that correct?

One other odd thing I noticed that may or may not be related: when I press the starter button sometimes it keeps turning over even after I release the starter button. It's no big deal because I can turn the key off but I'm wondering if it is a symptom of the problem.

Anybody have any troubleshooting ideas? Would it be possible to put a bag of ice any electrical parts to see if it made any difference?
 

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The starter thing is normal. It will turn over for I think four seconds and stop if the engine doesn't start. You don't have to hold when starting. Just touch it and the rest will happen without you.
 

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Sounds like an electrical resistance issue. As things heat up the resistance increases and starts interfering with the regular functions of the bike. The only time I had an unusual starter issue where it seemed to keep going longer than it usually did was when I baked the solenoid connector wires. Maybe once you get it to the point that it's giving you issues, pull the seat and feel along the wire loom and off shoots. If you find an any that are unusually hot you may find a short or poor ground. Not the most technical approach, but my own short badly melted the wires under the wrap prior to melting down my solenoid and connector. It was a lot of heat.
 

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Discussion Starter #9
The starter thing is normal. It will turn over for I think four seconds and stop if the engine doesn't start. You don't have to hold when starting. Just touch it and the rest will happen without you.
Ah, ok. I only notice it when I'm having problems because the bike fires right up other times.
 

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Discussion Starter #10
Sounds like an electrical resistance issue. As things heat up the resistance increases and starts interfering with the regular functions of the bike. The only time I had an unusual starter issue where it seemed to keep going longer than it usually did was when I baked the solenoid connector wires. Maybe once you get it to the point that it's giving you issues, pull the seat and feel along the wire loom and off shoots. If you find an any that are unusually hot you may find a short or poor ground. Not the most technical approach, but my own short badly melted the wires under the wrap prior to melting down my solenoid and connector. It was a lot of heat.
I remember reading here about people having electrical problems like that. I probably should check my grounds. My problem starts going away when I get out of traffic and can bring the temps down. I'm thinking that 35mph in 70 degree temperature wouldn't be enough to significantly cool an electrical short but who knows.
 

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Discussion Starter #11
dont really know, but my air pressure/temp sensor in the airbox went nuts and gave unpredictable results
Did the temp on your gauges go haywire as well? I've had some vehicles that had separate temp sensors for the gauges and fuel injection systems but I suspect the Brutale has only one (though I don't know). I'll look up and see how much that airbox sensor costs - might try replacing it as a simple test since I will be removing the gas tank soon to switch to metal fuel line couplers.
 

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Discussion Starter #12 (Edited)
fueling problem. Have it dynoed and mapped
Also put the heavy battery leads in, as above time for a tune . Bleed valves adjustment Tps reset etc
Maybe I should have it tuned but I'm scared of what the results may be. Except for this problem, the bike runs wonderfully. The previous owner warned me about messing with the tuning - he said it took Moto Forza a lot of time to get it to run this good. And the MV Agusta place here in Seoul doesn't look prosperous. When the wife and I first walked up to the store, we thought it had gone out of business. I'm afraid I'll just compound my problems if I take it there.

Does anyone have a diagram of the fuel injection components? Like sensors, ecu, etc. so I could get a better idea of how it works?

What is the bleed valve adjustment?

Also, does the cooling system on my bike need to be 'burped' to eliminate air pockets?

ETA: And heavy battery leads would be good although I don't think they are the direct cause of this problem. Where do they sell them?
 

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Did the temp on your gauges go haywire as well? I've had some vehicles that had separate temp sensors for the gauges and fuel injection systems but I suspect the Brutale has only one (though I don't know). I'll look up and see how much that airbox sensor costs - might try replacing it as a simple test since I will be removing the gas tank soon to switch to metal fuel line couplers.
No everything normal, apart from unsuspected begavior on fueling.
orig sensor is not chheap, chinese on ebay lots cheaper.
try at dealer first before buy

I think euro3 bikes have two temp sensors, one for ecu, other for dash, see elec drawing
 

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ok,here we go again.

Change plugs to Iridium

1=buy vdst software to suit your 5sm ecu
2=with the software you can reset your tps (throttle position sensor)

3=buy a carbtune or similiar to sync your air bleed valves.

4=if you do not want to buy above ,do this starting with cyclinder number 2 turn it in to dead stop then count 1 1/2 turns out ,adjust all other 3 bleed screws out 1 1/2 turns out.check your idle with the vdst software.now min turn out can be anywhere from say 1/2 turn out to 3 turns out.try and get your idle to 1150 rpm to 1200 rpm.

4= adjust fuel trim using vdst software to fine tune the idle,most of the time adjustment is towards the - side .for example -35 in the software.use your ear to find what the bike likes,i use a Co meter and set it to 13.6 to 1 a/f ratio.

5= buy a PC5 and have it dyno tuned.

6= good luck works fo me everytime also have done exactly the same to a b 1090.

cheers eddy

ps:air bleed screws can be at different turns out ,thats why you should get the carbtune,they connect to the 2 rubber air hoses on each side of your bike.they are market 1and 2 and 3 and 4 on the little black caps about half way down the bike on each side,look you will find them,they lead to your throttle bodies
 

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Oldbutspry,you have to buy some equipment Mate,otherwise it will drive you crazy,trust me i learnt the hard way.
 

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Discussion Starter #19
ok,here we go again.

Change plugs to Iridium

1=buy vdst software to suit your 5sm ecu
2=with the software you can reset your tps (throttle position sensor)

3=buy a carbtune or similiar to sync your air bleed valves.

4=if you do not want to buy above ,do this starting with cyclinder number 2 turn it in to dead stop then count 1 1/2 turns out ,adjust all other 3 bleed screws out 1 1/2 turns out.check your idle with the vdst software.now min turn out can be anywhere from say 1/2 turn out to 3 turns out.try and get your idle to 1150 rpm to 1200 rpm.

4= adjust fuel trim using vdst software to fine tune the idle,most of the time adjustment is towards the - side .for example -35 in the software.use your ear to find what the bike likes,i use a Co meter and set it to 13.6 to 1 a/f ratio.

5= buy a PC5 and have it dyno tuned.

6= good luck works fo me everytime also have done exactly the same to a b 1090.

cheers eddy

ps:air bleed screws can be at different turns out ,thats why you should get the carbtune,they connect to the 2 rubber air hoses on each side of your bike.they are market 1and 2 and 3 and 4 on the little black caps about half way down the bike on each side,look you will find them,they lead to your throttle bodies
Plugs were just changed to Iridium.
How about this diagnostic software? Or is there something else that would be better:

http://www.technoresearch.com/index.php?pid=37
 

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That's ,the one. Now the only 2 things this software will do is 1= reset your tps and 2= adjust fuel trim.

It will also show you rpm and battery volts etc . and also has some basic tests.

But you will need it .Unless there is someone near you who could do it.

cheers eddy
 
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