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ANSWERED V11 Engine Hot Rodding advice

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As an tangential anecdote;

I play with classic cars, and have a good friend in the restoration business. Primarily he's concerned with Chrysler products of the 60s and 70s. 
One of his regular customers asked if he'd return to service a pristine MG Midget that had been parked for a decade. He asked if I'd help, because I have some experience with English cars and bikes. After the typical fuel system service and fluid changes, it came to life quite easily, all under the criticism of my friend. "Go-cart" "Tiny motor" "Why would anyone bother?".
Needless to say, he drove it around for a full week, taking it everywhere including a car show. When I pressed him to admit it was a good time, of course he did; What we isolated as the true source of the fun was that you could drive the car about as hard as you cared to, without risking limb and license. Banging up through third gear with your foot on the floor and the top down is different but almost as good as blowing the tires up on a '70 440 'Cuda, and a lot less likely to attract points to your license.
Point being, I spent most of my life searching for performance improvements in everything I ever owned, only to discover that a great deal of it would have been better spent riding what was there instead of working on it. 
A 'Guzzi is what it is. Trying to make it something else may be fun and satisfying, but if the actual research and development isn't a good time in itself, it isn't worth the loss of actual riding time.  I ask myself, "How often am I actually at WOT?" Rarely. I do, however, take the time to fine tune what's there and I separate projects now so I can pursue what I feel like at the moment. 
<shrug> Defining the ends to our means is important.

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Honda sells a ton of Groms. Thing is, you can ride them WOT all day, every day - and no one but you knows this. Meanwhile you are ginning like an idiot inside your helmet. A form of the "Big, dirty fun" of which P.J. O'Rourke wrote. .

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2 hours ago, po18guy said:

Honda sells a ton of Groms. Thing is, you can ride them WOT all day, every day - and no one but you knows this. Meanwhile you are ginning like an idiot inside your helmet. A form of the "Big, dirty fun" of which P.J. O'Rourke wrote. .

A Monza is like that.. and you look cool doing it. :rasta:

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6 hours ago, po18guy said:

Honda sells a ton of Groms. Thing is, you can ride them WOT all day, every day - and no one but you knows this. Meanwhile you are ginning like an idiot inside your helmet. A form of the "Big, dirty fun" of which P.J. O'Rourke wrote. .

So true. Low power, light weight bikes can be a hoot to throw around. The price of poor judgement or technique usually isn't as costly as on their big brothers.

Back in the early 80's when I was a young beat cop, senior police management came up with the misguided notion that it would be a good idea to create a more mobile beat squad and equipped us with a fleet of silver Honda CB200s.

They were the epitomy of an unmanly/non macho motorcycle, but we never had so much fun on bikes in all our lives. There were legendary crashes into the Rideau Canal, jumps off the Carlington Ski Hill, we even ran our own Moto GP on the bike paths & parkways in the middle of the night when no one was around, many smiles generated by the lowly CB200 :grin:

Kelly

 

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I've maintained for maybe 15 years now that the most sports bike anyone needs on the road is any of the current crop of 600cc Super sports bikes. more power than you can sensibly use and light weight. I stopped riding my Ducati 1198 on the street about 8 years ago when I realised it was just too much bike for the road.

Best fun ever had on 2 wheels period.......a day zipping about Rome 22 years ago on a hired scooter. Dont even know what the engine size was,didnt seem to matter.

Ciao

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1 hour ago, Lucky Phil said:

I've maintained for maybe 15 years now that the most sports bike anyone needs on the road is any of the current crop of 600cc Super sports bikes. more power than you can sensibly use and light weight. I stopped riding my Ducati 1198 on the street about 8 years ago when I realised it was just too much bike for the road.

Best fun ever had on 2 wheels period.......a day zipping about Rome 22 years ago on a hired scooter. Dont even know what the engine size was,didnt seem to matter.

Ciao

Power is fun and all but when you're on public unmaintained roads with 120+hp pounding a corner and you feel your rear wheel starting to break free as your butt puckers... Now we see RSV4s with 190rwhp with a map and pipe... My ADD couldn't handle it...😅

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19 minutes ago, Rox Lemans said:

Power is fun and all but when you're on public unmaintained roads with 120+hp pounding a corner and you feel your rear wheel starting to break free as your butt puckers... Now we see RSV4s with 190rwhp with a map and pipe... My ADD couldn't handle it...😅

Yes but even with a 120 HP, new bikes have ABS and Traction Control.  I don't think I'd want 190 hp bike without all that.  

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23 minutes ago, Rox Lemans said:

Power is fun and all but when you're on public unmaintained roads with 120+hp pounding a corner and you feel your rear wheel starting to break free as your butt puckers... Now we see RSV4s with 190rwhp with a map and pipe... My ADD couldn't handle it...😅

Yep, around 100 RWHP is about all you can use on a road bike I think. I'll trade anything over that for reduced weight every day of the week. A mate and I used to ride with a guy that owned a Blackbird then a Hyabusa then a ZX1400. He couldn't ride out of sight on a dark night but just had to have whatever the latest bike with the most horsepower was. Me and my mate were on Older Ducatis etc and would see him about 10 min after we got to the coffee shop. I pointed out to him that we had half the HP and 2/3 the weight so what was the point in a big lardy Hyabusa etc but he couldn't tear himself away from the latest and greatest syndrome.

Although those that ride them tell you how you dont feel the weight when you're moving they tend to be lost for words when you point out that you tend not to feel the bulk until you're in a sketchy situation then the weight comes and bites you on the ass.

Ciao     

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5 hours ago, 80CX100 said:

So true. Low power, light weight bikes can be a hoot to throw around. The price of poor judgement or technique usually isn't as costly as on their big brothers.

Back in the early 80's when I was a young beat cop, senior police management came up with the misguided notion that it would be a good idea to create a more mobile beat squad and equipped us with a fleet of silver Honda CB200s.

They were the epitomy of an unmanly/non macho motorcycle, but we never had so much fun on bikes in all our lives. There were legendary crashes into the Rideau Canal, jumps off the Carlington Ski Hill, we even ran our own Moto GP on the bike paths & parkways in the middle of the night when no one was around, many smiles generated by the lowly CB200 :grin:

Kelly

 

Never wanted to be a motor cop. Bikes way too big and one had to have the balance of a circus performer to make a simply u-turn. I would have been sorely tempted had they purchased KLR650s or similar - something big enough, but more suited to easy maneuverability. The Super Motard style now would be excellent. 

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19 hours ago, Pressureangle said:

Re; high compression pistons.

The historic battle within hemispherical combustion chambers is always between compression and detonation. Firstly, in the U.S., the DOT mandates than anything sold for highway use operate on 87 octane fuel without destroying itself. So, if you're willing to use premium always (who doesn't, anyway?) there is a little room for increases.
Here's where things get messy.
Firstly, tuning an engine to take advantage in the difference between 87 and 93 octane is something only an expert with a dynomometer, or a very experienced butt and ears, can do meaningfully. Secondly, there really isn't that much difference anyway. If you're capable of such, you're also capable of tuning your intake and exhaust, fuel and timing as is to achieve 80% of the difference with such a mild compression increase. 
Lastly, altitude and camshaft have huge effect on cylinder pressures, particularly at the medium RPM range where detonation is most prevalent. 
Hemispherical combustion chambers are the most efficient design from the perspective of (2-valve) valve/flow size and efficiency. But they are the worst for detonation. 
The most effective counter to detonation is turbulence during compression, which achieves 2 specific things; improves homogenization of the mixture which removes 'dead' or 'late' spots in the burn; and speeds completion of burn which removes unburned mixture from corners which overpressure and detonate. 
Without enormous and expensive changes, there's little we can do with stock Guzzi castings to improve squish, which creates turbulence. What I did on my LM1000 though, was to carefully measure quench-the actual distance between the piston and head- to be certain it was optimized. The term 'quench' is used, because it's known that the fuel/air mix *cannot* ignite within a narrow margin of distance. That distance is somewhere between .050" and .025". It's typically recognized that the worst contained distance for detonation with gasoline is about .080". 
You can measure your quench with a piece of soft solder through the spark plug hole, to discover to some degree where you are and if taking a little off your cylinders may have some benefit. IIRC I took about .015" off the LM, which raised the compression by about half a point. 
That said, it has a Web 86b camshaft, which although has far more lift than the stock cam, also creates much more cylinder pressure in the low RPMs. The combination requires that I retard the timing a couple degrees from stock to kill any apparent detonation. Tuning is ongoing, currently. 

I always read these back before posting, and I'm never sure they convey sufficiently the information. :/

In Australia, we have 98octane fuel which pretty much every bike rider uses in their machines FWIW.

I ran a similar FBF in my ST2 with a bunch of mods, with about 10hp gain. I am still in the process (slack to finish) tuning my V11.

Im not running an airbox but have made velocity stacks with big K&N filters, and the FBF pistons which i think are .5 up on compression for memory. I have a fully programmable ECU to fit as well. The bike runs reasonably well and definitely has more HP over stock.  

Do we every reeeeally finish tuning our bikes?????

 

 

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49 minutes ago, knumbnutz said:

 

Do we every reeeeally finish tuning our bikes?????

 

 

NOOOoooo...

I installed a Jeffries ECU in my 1100 Sport-i and tuned it well enough to take on a `10k tour last year, refined it through the first half, trimmed it the second half, and touched it up a little this year before the South'n Spine Raid. I think I've convinced myself it's close enough to work on the other projects now lol. 

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4 hours ago, knumbnutz said:

In Australia, we have 98octane fuel which pretty much every bike rider uses in their machines FWIW.

I ran a similar FBF in my ST2 with a bunch of mods, with about 10hp gain. I am still in the process (slack to finish) tuning my V11.

Im not running an airbox but have made velocity stacks with big K&N filters, and the FBF pistons which i think are .5 up on compression for memory. I have a fully programmable ECU to fit as well. The bike runs reasonably well and definitely has more HP over stock.  

Do we every reeeeally finish tuning our bikes?????

 

 

Keep in mind that our octane ratings use a different scale than yours do. We have typically the same three grades, but ours go; 87, 89, and 91 - 93 depending. We used to have one brand that offered 94, but they seem to have pulled that. Our three grades should be roughly the same as yours, the numbers being different is due to us using an average of MON and RON while you guys use just the higher number.

As to the original aspect of this discussion, high compression pistons, I am a fan. But not so much the FBF version. The Mike Rich version has always looked like a better design to me. FBF increases the compression mainly by raising the dome. That does raise compression, but it hurts the effective combustion chamber shape (the shape cast into the head minus the shape cast into the piston). The Mike Rich design focuses a lot on reducing the squish area (or "quench" as Pressureangle referred to it as). The stock design has fairly poor squish around the perimeter of the piston. I also worked to improve that on the wifes V11, having a machine shop machine down the surface of the heads to increase that lip and machine down the cylinders to set the piston height right where I wanted it. As mentioned, the idea being that when the piston comes up it should right up to the head, just missing it. How close depends on how tight you want to push it. I tend to push it, as that is what we always did with our Ducati's. So to me, the piston should be about the thickness of the head gasket from the head. Others will want more clearance, no doubt. Either way, that closeness increases compression and also increases the swill in the combustion chamber. That allows you to run higher compression without the corresponding increase in detonation.

The hemi shape as used in our Guzzi 2 valve motors is OK. It is hard to get great compression and combustion out of it without forced induction. And not many people use forced induction on their Guzzi. The 4 valve / 8 valve Guzzis do have a better combustion chamber shape. How much better I am not sure, especially with the modern 8 valve motors. I say that because one good indicator of combustion chamber shape is fuel mileage. All else being equal (bike size, weight, gearing) a motor with a better combustion chamber shape will get better fuel mileage than one with a lesser combustion chamber shape. And everything I hear about the new 8 valve motors is they get worse fuel mileage than the same motorcycle with the previous 2 valve motor. So, unless the cam shaft is really F'd up, it seems like the new 8 valve motors are not the efficient at burning fuel. This is not about max potential power output, riding down the road the two are doing the same amount of work and thus the power being produced is the same. This is about efficiency. And the newer 8 valve motors don't seem to have it. Odd, because many other similar sized twins can and do get really good fuel mileage. My wifes Monster being a good example.

In my experience, higher compression has a direct usable improvement in street use. It gives the motor more snap, more instant response, to throttle inputs. It is more about increasing torque than increasing horsepower. And that is very helpful on the street.

While Guzzi's are cool as they are, one thing I like about them is how relatively easy it is to make them better than they came out of the factory. This is completely different than, say, a Yamahonduki 1400 which is already engineered to be about as fast as it could be made to be. There is a lot left on the table with Guzzi engineering. Unlike the modern Japanese engineers, a Guzzi simply is not refined to where you can't really make it better / faster.

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The '04s are listed at 9.8:1. With air cooling and the deep combustion chamber, it seems to be a reasonable maximum for the street. Spraying decongestant on the airbox and mufflers would be most cost-effective, methinks. I'm halfway there, considering the airbox now. 

As to ECU re-flashes, anyone know who is good and reliable at this in the US?

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Todd at Guzzitech in CA flashed my V11 Sport, it has run like a top since, try him at:

todd@guzzitech.com

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Many thanks! Might have been re-flashed, but PO didn't know.

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