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Discussion Starter #1 (Edited)
In 2012 I purchased a new F4 1000RR, it runs ok now but the exhausts are always very, very sooty at the back, the bike as been in and out of the garage several times but no fault can be found. I have a theory can any body add/help?:)

I believe the 2012 RR was made using only two piston rings so that 201bhp could be achieved.:jsm:

Does any body know how many piston rings there are in the new 2013 F4 1000RR ? I,m thinking that the 2013 model has been made using three piston rings and thats why MV say its bhp is now only 196 and I have also noticed when I have seen pictures of the exhausts on the new 2013 bike they are always very clear.:jsm:

If my theory is correct the 2012 model has sooty exhausts because its burning oil.:jsm:
 

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Maybe to test that theory you would have to get a cylinder leak down test done and some time on the dyno with a gas analyser. A lab test of the oil might show something too.
How was the bike run in? One of our local guys swears modern bikes should be run in with mineral oil to get the rings to bed in properly. He reckons running synthetic too early causes the cylinders to get a glaze and then the rings don't do their job.
 

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Stephen,

How many miles on the 2012?

I ask because my 1199S burned oil all the way until 2000 miles.
 

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MVs have Nikasil coated cylinders and honed chrome rings

my MV uses ZERO oil, my Aprilia RSVR has Nikasil coated cylinders and uses ZERO oil

my BMW R1150GS at 58,000mi sucks oil like a Hollywood starlet chasing free white lines on a mirror

at 10,000mi it used 3/4 quart in 250mi.....LA to San Diego and back

now its down to less than 3oz/250mi

it doesn't have honed rings OR smooth bores:wtf::wtf::wtf:

Stephen;
put a lambda meter on it, guaranteed its fueling, not oil
 

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I read that the 2012 RR only had two rings on the piston, but can't remember where I read it? anyone else find this?

As Steve says oddly the 2013 RR is 5hp down on the dyno from the 2012 model.is this MV returning to a 3 ring set up after too many ''sooty'' back end of the bike complaints?

You could always get the bike on a 4 gas analyser or even a 3 gas analyser, that may show up high hydrocarbons on the over run suggesting oil is getting past the rings?
 

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U r probly close to the mark... I'm betting the sotty back end is oil and not fuel (like normal) for one very good reason.. My 2010 F4 runs very clean, rarely have to clean the tips.... Until u pull a wheelie, at which point the bike sucks oil into the airbox, and without fail on the next start up will blow a heap of smoke out the exhaust, it clears up after 30 seconds or so but on that ride the tail pipes will get very sooty.... Get home clean them off and on the next ride it wont happen

It only gets sooty when it sucks oil, and i should point out its only a very small amount, just need to set up a catch can on mine.... So i would assume your problem could also b oil related
 

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U r probly close to the mark... I'm betting the sotty back end is oil and not fuel (like normal) for one very good reason.. My 2010 F4 runs very clean, rarely have to clean the tips.... Until u pull a wheelie, at which point the bike sucks oil into the airbox, and without fail on the next start up will blow a heap of smoke out the exhaust, it clears up after 30 seconds or so but on that ride the tail pipes will get very sooty.... Get home clean them off and on the next ride it wont happen

It only gets sooty when it sucks oil, and i should point out its only a very small amount, just need to set up a catch can on mine.... So i would assume your problem could also b oil related
MV Service bulletin says run oil at min level.
 

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Donsy where is the service bulletin, and when was that posted? As my bike was just serviced and if anything was slightly over full
 

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I don't know of any modern 4 stroke engine that utilizes a 2 ring system. Even my 1930 J.A. Prestwich twin uses a 3 ring system. Furthermore, other than a negligible reduction in friction resistance via one less point of friction and minimal contribution to moving mass (possibly), I can't see how 2 rings would produce more horsepower to that degree?
 

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Piston rings are about the highest frictional loss in a modern 4 stroke engine.losing 33% of them helps enourmously with horsepower, a lot of this goes on in drag racing,
Porsche also tried it for one year of the 997 GT3 RSR engine, but reverted back to 3 rings again, one ''hidden'' advantage of 2 rings over 3 is you can also make a longer connecting rod and optimise the piston to rod to crankshaft angles.

I remember reading this about the RR engine, I certainly did not dream it, MV dreams are a thing of the past these days :)

There is another reason as well, the 2013 RR motor is quoted at 4.2kw (nearly 6hp) less than the 2012 motor, the rings could explain this :)
 

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Looks like three rings to me.
Piston rings are about the highest frictional loss in a modern 4 stroke engine.losing 33% of them helps enourmously with horsepower, a lot of this goes on in drag racing,
Porsche also tried it for one year of the 997 GT3 RSR engine, but reverted back to 3 rings again, one ''hidden'' advantage of 2 rings over 3 is you can also make a longer connecting rod and optimise the piston to rod to crankshaft angles.

I remember reading this about the RR engine, I certainly did not dream it, MV dreams are a thing of the past these days :)

There is another reason as well, the 2013 RR motor is quoted at 4.2kw (nearly 6hp) less than the 2012 motor, the rings could explain this :)

?????
 

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I'm not 100% sure you can go off a parts diagram Donsy, I think they may not alter the diagram from one model to the next
 

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I guess that makes you Lord of the Rings then Mike.
Good luck on your journey to identify the missing ring - the ring to fool all others.
 

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I dont get it... If it burns oil you know that I would think...
What a theory... :wtf:

Maybe I am ignorant :stickpoke
 

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Piston rings CAN be up to 20% of friction loss in an engine, WHEN applied to improperly sized rings, improper ring material, AND unlined cylinders. That is a perfect storm of events there. A more accepted theory is that average is 8-12% of frictional loss is possibly to rings. With frictional losses only being 1 source of loss in an engine. Furthermore, the frictional loss of each ring isn't linearly parallel in performance. Eliminating one ring may result in anything from 15% to 45% of friction loss, depending on ring spacing, face area, etc.

Even at that - 33% of 8% of a partial amount isn't really that much. I still don't see eliminating one ring as a 6 HP increase.

AND if they eliminated the oil ring, then the oil leakage would constitute an inefficient fire, and lower HP. If they eliminated a compression ring, they would have more blow by, and lower compression - again lowering horsepower. You could increase the compression ring face area - but then you increase the friction loss, near where it was.

Back to the original diagnosis - black exhaust, IF it is from oil, will have a gritty, and slightly "oily" appearance. If it is just black, then that is "richness".
 

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guys, I don't know where you are getting your data, but official site still says 201 HP for the 2013 RR.

2012: http://www.mvagusta.it/it/f4/f4rr?aprix=techdata;funcax=fnProductFeatures()#techdata

2013: http://www.mvagusta.it/it/f4/f4-rr-my13?aprix=techdata;funcax=fnProductFeatures()#techdata

About the rings; I can't be sure, nothing official is on the site.

Also; I talked to Brian Gillen few weeks ago at the Aragon race; I was told that 2013 is basically a new engine, new head, new oil system, new electronics as now is FBW, new head, new pistons, new rods, like I said basically a new engine.
It's one mighty engine, I hope they sorted the fueling out...
 

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Piston rings CAN be up to 20% of friction loss in an engine, WHEN applied to improperly sized rings, improper ring material, AND unlined cylinders. That is a perfect storm of events there. A more accepted theory is that average is 8-12% of frictional loss is possibly to rings. With frictional losses only being 1 source of loss in an engine. Furthermore, the frictional loss of each ring isn't linearly parallel in performance. Eliminating one ring may result in anything from 15% to 45% of friction loss, depending on ring spacing, face area, etc.

Even at that - 33% of 8% of a partial amount isn't really that much. I still don't see eliminating one ring as a 6 HP increase.

AND if they eliminated the oil ring, then the oil leakage would constitute an inefficient fire, and lower HP. If they eliminated a compression ring, they would have more blow by, and lower compression - again lowering horsepower. You could increase the compression ring face area - but then you increase the friction loss, near where it was.

Back to the original diagnosis - black exhaust, IF it is from oil, will have a gritty, and slightly "oily" appearance. If it is just black, then that is "richness".
8% of 201 hp is 16 hp, 33% of 16hp is around 5.3hp. :)

They have one compression and one oil control ring when they use two rings, normally the engine is dry sumped and uses a system to reduce the crankcase pressure to below atmospheric pressure, the dry sump scavenge pump can do this

If you get Steves bike hot on a sunny and still day and rev it to around 6-7000rpm there is what appears to be a slight oil mist on the over run, like I say it needs to be a perfectly still day, any slight breeze or lack of sun and you would not see it
 

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I guess that makes you Lord of the Rings then Mike.
Good luck on your journey to identify the missing ring - the ring to fool all others.
I don't know where the hell I read it Dave, I have searched the web and can't find any reference to two rings anywhere,

But I did read the article with some interest to see if they also lengthened the connecting rods, this can also give a lot of 'free' hp as it can change the sidewise thrust of the piston into an added thrust to the crank,

This is one of the problems when people build Mitsubishi EVO's with what is called a 'stroker' kit...........they wear the piston skirts out

PS: just a quick link:

http://victorylibrary.com/mopar/rod-tech-c.htm
 
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