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Discussion Starter #1
Video linked below...

Not sure if sprag or some other issue. Heard the dreaded sprag bang a couple of times. Seems to happen most during first start of day.
Brand new 2018 engine with about 3,500 miles on it. Before I dropped valve on my old engine the sprag needed to be replaced around the same milage.

https://youtu.be/KOLfIRX0lw0
 

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It is hesitating the way the sprag issue does. But it doesn't have the clack sound that I've heard. So, not really completely sure. Unplug the lines from the bottom of the fuel tank for overflow and evap and then see how it does. If you've got a leak in those lines or have them crossed over you can get hard starts as well.

I'm on the fence based on the video if it is sprag or not.
 

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Discussion Starter #3
I'm on the fence too. It just started happening so I do not think the fuel lines are crossed. I'll have dealer double check the lines since they put the new engine in.

I also filled up my tank too much one day and it leaked from the overflow tube to the bottom of bike so the lines seem to be correct.

It is hesitating the way the sprag issue does. But it doesn't have the clack sound that I've heard. So, not really completely sure. Unplug the lines from the bottom of the fuel tank for overflow and evap and then see how it does. If you've got a leak in those lines or have them crossed over you can get hard starts as well.

I'm on the fence based on the video if it is sprag or not.
 

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Not touching the throttle ??? You shouldn't be if you are. Sounds more like a lean cold start situation...
 

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Not touching the throttle ??? You shouldn't be if you are. Sounds more like a lean cold start situation...
I agree.

If I start my F3 800 after more than 2 weeks of not using it, I get this same way of starting.
Once it has fired up it starts OK after you stop it.

From a set op cheap starter cables and 10A Anderson conectors I made a jump starter set.
At cold start I hook up an extra battery.
With the extra Amps (and revs) of the extra battery it starts almost immediately and I hope the sprag clutch will last longer.

Not ideal but does the trick for me.
 

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Discussion Starter #6
Not touching the throttle and I start bike every day and ride it. Every now and then it does the same after it is warmed up. I upgraded all the battery cables when new engine was installed.

Throwing in some headers and a can some time soon with a new map so I guess I'll know then.

Bike just came out of warranty but I should be covered if it's the sprag.

Not touching the throttle ??? You shouldn't be if you are. Sounds more like a lean cold start situation...
Not touching the throttle ??? You shouldn't be if you are. Sounds more like a lean cold start situation...
I agree.

If I start my F3 800 after more than 2 weeks of not using it, I get this same way of starting.
Once it has fired up it starts OK after you stop it.

From a set op cheap starter cables and 10A Anderson conectors I made a jump starter set.
At cold start I hook up an extra battery.
With the extra Amps (and revs) of the extra battery it starts almost immediately and I hope the sprag clutch will last longer.

Not ideal but does the trick for me.
 

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A modern vehicle should not behave like what is happening in your posted video. Something is definitely not right.
Due to having multiple bikes, sometimes my MV might go up to 10 days sitting under the covers. I have found that the starter motor time is reduced if I turn the key on, then allow 5-10 seconds for the fuel pump to prime the system before I hit the start button.
As posted above, it would appear to be a lean start issue. I would be looking through the fuel system and doing a renovation - fuel filter, injector clean, check air filter, tank vent hoses etc. while the air box is off, have a look down the inlet manifolds to check for any build up on the inlet valves and in the inlet tract.
Don’t forget to check all the rubber tubes and caps for any possible air leaks, which will give a lean condition.
Whilst they are in there, I would ask for the related sensor connectors to be unplugged, cleaned and lubed and then re assembled.
 

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Discussion Starter #8
Wondering how these two factors come into play...if they do.

Used different gas yesterday than my normal station and started bike later in day when it was much warmer out and bike started right away.

Hmm...
 

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wtf????

It is hesitating the way the sprag issue does. But it doesn't have the clack sound that I've heard. So, not really completely sure. Unplug the lines from the bottom of the fuel tank for overflow and evap and then see how it does. If you've got a leak in those lines or have them crossed over you can get hard starts as well.
airjawed;
YOU HAVE NO CLUE ABOUT WHAT IS GOING ON, PLEASE STOP POSTING ERRONEOUS CRAP OR HEARSAY, YOU'RE NOT HELPING!

This is an International Forum, many people speak no English and Google Translator is useless for technical terms

This isn't the 1st time I've said this to you!!!

STOP
 

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Yes 93 USA so of course it has ethanol...
Non ethonal 98 is about 10 bucks a gallon here.
BP 98 here this arvo...$1.80 AUD a litre (just filled it anyway).

My car is designed to run on that cheap (ethanol infused) crap if need be but the bikes?

No way mate...fill it up with 98.
 

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Might just be a coincidence that it started well after fuel station change. Keep us updated on the issue. It might end up being sprag so lets not get hopes high!



Wondering how these two factors come into play...if they do.

Used different gas yesterday than my normal station and started bike later in day when it was much warmer out and bike started right away.

Hmm...
 

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I've been through a few sprag replacements. One of which was definitely made worse by having the lines on the bottom of the fuel tank crossed by the last person who worked on bike(which was not me).


I'm flattered by your need to try and manage my posts on the internet. Please continue with your hypocrisy.



airjawed;
YOU HAVE NO CLUE ABOUT WHAT IS GOING ON, PLEASE STOP POSTING ERRONEOUS CRAP OR HEARSAY, YOU'RE NOT HELPING!

This is an International Forum, many people speak no English and Google Translator is useless for technical terms

This isn't the 1st time I've said this to you!!!

STOP
 

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Same problem

with a F3 that hesitates to start.

I connected my special charger and after one night the problem of difficulties to start is gone.
So it might be your battery that is in the brink of giving up unless you try a "smart" charger
This is my 2 cents of the problem

I replaced my original battery after 3 years, and my current battery is 1 year and if I park the bike more a couple of days I connect the charger

//Fredrik
 

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First time MV Agusta owner here.

I purchased my 2014 Brutale 800 just 3 months ago from the local dealership here in Las Vegas, NV. The bike had 8900+ miles on it already. I noticed a few weeks ago it would take more than one try to start the engine. And it has slowly gotten worse until this past weekend when it wouldn't start at all after I initially started it for the first time that day. I would hear a banging noise (a couple of you on this thread referred to as the sprag clutch bang). I had already replaced the spark plugs and battery already (thinking they may have been the issue, but it wasn't). I reported the incident to the dealership. Without even looking at it, they informed me of the sprag clutch issue with the Brutales and may be able to get it replaced under a warranty/recall item as long as the bike had not already had the sprag clutch replaced for the same issue. They are putting in the claim and waiting to hear back if it has or has not been replaced. The dealership will be arranging to pick up the bike from my house next week to have diagnostics run on it but they are pretty sure it's the sprag clutch based on what I reported and showed on video through my phone.

I say all that to ask this. Is this going to be a part that will need to be monitored regularly and replaced one, two, three or more times (depending on mileage I put on it) as I continue to own the bike? Is there anything I can do as preventative maintenance in regards to that part . . . ?
 

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Discussion Starter #17
Only thing you can do is get a lithium ion battery if bike does not have one already.

First time MV Agusta owner here.

I purchased my 2014 Brutale 800 just 3 months ago from the local dealership here in Las Vegas, NV. The bike had 8900+ miles on it already. I noticed a few weeks ago it would take more than one try to start the engine. And it has slowly gotten worse until this past weekend when it wouldn't start at all after I initially started it for the first time that day. I would hear a banging noise (a couple of you on this thread referred to as the sprag clutch bang). I had already replaced the spark plugs and battery already (thinking they may have been the issue, but it wasn't). I reported the incident to the dealership. Without even looking at it, they informed me of the sprag clutch issue with the Brutales and may be able to get it replaced under a warranty/recall item as long as the bike had not already had the sprag clutch replaced for the same issue. They are putting in the claim and waiting to hear back if it has or has not been replaced. The dealership will be arranging to pick up the bike from my house next week to have diagnostics run on it but they are pretty sure it's the sprag clutch based on what I reported and showed on video through my phone.

I say all that to ask this. Is this going to be a part that will need to be monitored regularly and replaced one, two, three or more times (depending on mileage I put on it) as I continue to own the bike? Is there anything I can do as preventative maintenance in regards to that part . . . ?
 
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