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Discussion Starter #1
only happens when I'm coming to a stoplight and downshifting. When I shift from 2nd to 1st it just shuts the engine off while passing through N. No problem restarting just would like to fix this problem any ideas? It has an arrow exhaust and chip. I wonder if that has anything to do with it??
 

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Welcome Lawler574,hmmm seem to have read about similar posts here. Do a search see what you find. Something about clutch switch, or sidestand switch that can cause that problem. There are many helpful members here.
 

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Idle speed is too low.... The reading on the tachometer is not very precise.

Of course, it could also be a fuel mixture or ignition timing issue, too. What chip is on your ECU?

Do you have a "lumpy" idle...like a hot-rod with a big cam? Is the stalling worse when cold? Does it only stall out after decel, and otherwise will sit and idle without stall. These are all symptoms of low idle speed...especially the "rump rump rump" lumpy idle.
 

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Discussion Starter #6
Not sure what chip is in there the previous owner put it on with the new exhaust but i do have the stock chip and exhaust. I'd say it does sound kind of like rump rump rump. It shut off on me twice today engine was at 154 degrees Fahrenheit. I was sitting at a light and it suddenly died. No signs of wanting to die but it started up and immediately did it again. Then later before I got home again was at a light and it almost died on me but I was holding the throttle just enough. Engine temp was around 170 degrees Fahrenheit.
 

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Discussion Starter #7
Idle speed is too low.... The reading on the tachometer is not very precise.

Of course, it could also be a fuel mixture or ignition timing issue, too. What chip is on your ECU?

Do you have a "lumpy" idle...like a hot-rod with a big cam? Is the stalling worse when cold? Does it only stall out after decel, and otherwise will sit and idle without stall. These are all symptoms of low idle speed...especially the "rump rump rump" lumpy idle.
To answer your questions I'd say yes its worse when its cold but has done it when it was hot and usually will stall on deceleration but the past couple times has been at a stand still. Doesn't matter if its in first or N.
 

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Idle speed for the Brutale 910S, according to the manual, and measured with the VDST system, is between 1100-1200 RPM
478300


I would be looking for a small vacuum leak.
 

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The lumpy idle is due to the idle speed being too low....which will also cause your stalling. As silentservice703 suggested, look for an air leak. Common spot is the vacuum caps on either side of the frame where the hoses to the intake spigots attach (used for throttle body synch), or the hoses themselves.
Do you still have the evaporative emissions system hooked up and the canister in your tank? This system can also be a source of problems including stalling.

Your dash tach is not accurate enough to see true idle speed....and I have found my 910 runs better at around 12~1300 rpm.
 

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Discussion Starter #10 (Edited by Moderator)
The lumpy idle is due to the idle speed being too low....which will also cause your stalling. As silentservice703 suggested, look for an air leak. Common spot is the vacuum caps on either side of the frame where the hoses to the intake spigots attach (used for throttle body synch), or the hoses themselves.
Do you still have the evaporative emissions system hooked up and the canister in your tank? This system can also be a source of problems including stalling.

Your dash tach is not accurate enough to see true idle speed....and I have found my 910 runs better at around 12~1300 rpm.
The previous owner mentioned removing the evap cannister idk why but he claimed they cause more harm than good. Sound like thats the problem?
 

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That all depends on how the P.O. removed the canister. If he did it correctly it does not cause an issue. Has this problem existed since you got the bike, or did it develop as time went on?
 

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The canister looks like this in a US bike:
478302


The red circled areas are areas where vacuum leaks can occur and are the areas affected by removing the can.

With the can removed, your system should look like this:
478303


With the evap can removed, the areas circles in red are the places where vacuum leaks most likely exist:

478304
 

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Discussion Starter #14
That all depends on how the P.O. removed the canister. If he did it correctly it does not cause an issue. Has this problem existed since you got the bike, or did it develop as time went on?
I've had the bike just over a week now he said he had this problem happen once but I'm sure thats not true lol but giving the vacuum lines a quick once over I didn't notice any leaks. Unfortunately I don't know a whole lot about bikes this size but I thought that it had something to do with the aftermarket exhaust and chip not being in synch with the proper air to fuel.
 

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Early on my Brutale did the same. It'll drive you nuts. Then Fast by Ferracci adjusted the idle speed. Runs perfectly to this day.

Afterward my evap was removed, then new hoses, fittings, vac caps. Lawler574 def look to see if the vac caps are in place. Chuck and Ed are spot on.

—Sometimes bikes are clean as can be because a problem was never resolved. I suspect this is the case with your bike. Don't sweat it... just a bit of time to resolve.
 

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The can was inside the tank.....

@Lawler574 ... that photo is the removed canister. Check the little caps on either side of the frame shown in Chuck's bottom diagram. They crack and leak, but may appear fine until you pull one off.
478305
 
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The can was inside the tank.....
Garbage in, Garbage out... The OP states his bike is an '06 and that diagram is the '05/06 910 parts diagram. The '07 diagram shows the can in the tank.

478307

478308
 

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I stand corrected !!! I thought they were all in the tank on first gen bikes. Living and learning.
Regardless, his is off now and the sealing caps are known to deteriorate.
 

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Id say get the fuel mixture checked, and put it on the lean side for idle, also this engine does not like to idle under 1250 - 1300 rpm range. It is very hard to get it not to stall! Mine idles approx at 1400 rpm, CO is way leaner than supposed on the manual, it is the only way to make this model engine idle properly. At least it is in this sea level.
 

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Discussion Starter #20
I'm finding a ground issue with my micro brake light switch. Do you think that could also contribute to the idle problem?
 
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