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Avgas and the oxy sencer


dangerous

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4 hours ago, dangerous said:

Shit guys... This thread was started over 14 years ago, things have changed. 

NZ now has 100oct unleaded at the pump, compared to a jap bike the Guzzi is higher compression and does benifit from higher Oct here, our 91oct is very shitty, I get a bit of engine pinking on it specially on hot days, 100 stops this. 

However since the thread started my bike had a completely different tune, exhaust is more open, filters are pods and the ecu is reprogrammed from an earler v11... Its never run so well. 

I know what the response here is going to be but unless you can provide a back to back run dyno sheet on the gains from removing the airbox I'll say you are dreaming about any gains from that. As for the "earlier V11 ecu" there will not be any performance difference between a 15M and a 15RC ecu. Some here claim the later RC is actually better but I dont see how that's true either. One supports a Lambda sensor and one does not. The RC has the Lambda facility which is nothing to do with performance and can be disabled with a few clicks of the mouse in Guzzidiag.

Ciao 

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11 hours ago, Lucky Phil said:

I know what the response here is going to be but unless you can provide a back to back run dyno sheet on the gains from removing the airbox I'll say you are dreaming about any gains from that. As for the "earlier V11 ecu" there will not be any performance difference between a 15M and a 15RC ecu. Some here claim the later RC is actually better but I dont see how that's true either. One supports a Lambda sensor and one does not. The RC has the Lambda facility which is nothing to do with performance and can be disabled with a few clicks of the mouse in Guzzidiag.

Ciao 

I agree with you, HP may not have been raised but the way it delivers has, it has a big hit at 5 and bigger at 6... It reminds me of a Daytona 4v

Again this might be cos I lost a hole shit load down low, so it feels like more. 

Basicly it runs richer and timing is ulteted, it's a tune sent to me from a German guy here 

Yes Ron in NZ if 100 is about your 91... I'd hate to think what our 91 is in us. 

 

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47 minutes ago, dangerous said:

I agree with you, HP may not have been raised but the way it delivers has, it has a big hit at 5 and bigger at 6... It reminds me of a Daytona 4v

Again this might be cos I lost a hole shit load down low, so it feels like more. 

Basicly it runs richer and timing is ulteted, it's a tune sent to me from a German guy here 

Yes Ron in NZ if 100 is about your 91... I'd hate to think what our 91 is in us. 

 

So it's got a shit map! Which German? Not that clown who's claiming to get 130+hp out of a flat tappet 1400?
 

Sorry, if I can be bothered I'll go through why this is wrong, again, but there again I'm so over it I don't think I can be arsed.

If you want to ride a truly 'Biggus Dickus' V11? Go and ride Chuck's Scura. First thing I did when I bought it was piss off the pod filters and reinstall the stock air box and a standard filter. Yes, it has a PC on it but at the time and with the 15M that was the 'Go To' at that time and it was obviously set up by someone who knew what they were doing and wasn't a snake oil salesman or spiv. That bike is BLOODY AWESOME and it's delivery is extraordinary from nothing to Blurp, Blurp, Blurp!

Blasting across West Texas at 'Faster than F*ck' speeds was effortless, riding it in the CA Canyons was a 'Stick it in third and gun it'.

The only difference between the 15M and the RC is Lambda input. Other than that it's the same ECU. If you leave the lambda on then the system will always try and trim the fuel to achieve the emissions target. Where does it do this? At operating temperature, (Above 60 degrees C.) and on a constant throttle below about 4,000-4,500 rpm! Screw about with your right wrist and it goes open loop. Above those crank speeds and below that temperature? Open loop!

If it feels like it has a 'Step' in its 'Power' at 5,000 and 6,000 and you like that? That's fine. But don't for a moment convince yourself that it's running optimally. It's not.

I need to go to bed.

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Going back to the question of compression and pinging;

The wife's V11 did the same thing, it would sometimes ping. Usually it was in the midrange under load. Backing off the throttle would make it stop, but where's the fun in that.

I pulled the heads, had the ports cleaned up (and the valves / valve guides replaced, they were worn), milled the heads down to increase squish (stock the heads have a bevel around the rim instead of a proper squish band), and milled the cylinders down to set deck height evenly (milled both cylinders, but milled one more than the other to make them even). I am running more compression as a result, but perhaps due to better squish the issue of pinging went away and it runs much better.

I would not run avgas in a Guzzi. That seems silly. No reason the run fuel with octane that high in a motor with compression so low. If you really do need ethanol free fuel you can buy that for around the same cost as avgas. But our bikes have been running gas with ethanol in it for their entire lives, it isn't without issues but it isn't then end of the world. If you are worried about it, drain the tank, let it dry out, and coat it with Casewell.

I am a fan of higher compression and good squish. The increased squish creates more turbulence in the combustion chamber, which improves burn and decreases the chance of detonation / pinging.

I am, at some point, planning on doing the same thing to my 2V Griso. First I need to replace the clutch. But while it is apart......

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fark me guys... what a grumpy bunch ya turned into... get a dose a covid in ya...

look, all im saying is my bike runs the best it ever has, and by the seat a dyno hauls beter than it ever has... from new it had a big dead spot at 3k NOW it dosent, it pulls harder than I remember it and iv put 80k on the shitter.

You cant beat the tune x factory they know best, BUT fucking BUT... they have to abide by emission controls... lean and leaner. Now while a lean mix can give more power with petrol (the opposite with diesel) thers a limit, im a builder not a machanic so dont know shit, but.. yes theres that bloody but again... by richening my bike up and I could only do this with a older ecu (guzzi diog at the time wouldent respond to it) with openish pipes and pod filters (I know cant beat the math of an air box, BUT I didnt want that look) it runs shit fucking hot... SO THERE, nananaaana na

 

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3 hours ago, dangerous said:

fark me guys... what a grumpy bunch ya turned into... get a dose a covid in ya...

look, all im saying is my bike runs the best it ever has, and by the seat a dyno hauls beter than it ever has... from new it had a big dead spot at 3k NOW it dosent, it pulls harder than I remember it and iv put 80k on the shitter.

You cant beat the tune x factory they know best, BUT fucking BUT... they have to abide by emission controls... lean and leaner. Now while a lean mix can give more power with petrol (the opposite with diesel) thers a limit, im a builder not a machanic so dont know shit, but.. yes theres that bloody but again... by richening my bike up and I could only do this with a older ecu (guzzi diog at the time wouldent respond to it) with openish pipes and pod filters (I know cant beat the math of an air box, BUT I didnt want that look) it runs shit fucking hot... SO THERE, nananaaana na

 

On the contrary, improving on the cheap, poorly built, factory tune is easy. If you start off working from the precept that factory maps are 'Lean' you simply don't understand how a closed loop system works.

The vast majority of factory maps are not lean but rich. Sometimes stupidly rich. The lambda input will pull fuel out of that map until it reaches the specified AFR.

Thing is though that closed loop only operates in certain areas. Most specifically above engine temperature of 60*C, constant throttle, between, or up to about 4,000-4,500rpm. Crack the throttle? Open loop, rich. Cold? Open loop, rich. Above 4,500rpm? Rich!

So when you buy a widget to 'Richen it up', or a map from a nong who tells you "They're lean to meet emissions" or simply turns the lambda off? All you are doing is making the motor run sub-optimally.

Now if you like the way your bike runs? Good on you! Even though the overfuelling will wear it out quicker. But don't for a minute believe that that series of steps in the power/torque delivery is optimal.

Carry on.

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Why would I ‘Forget’ your bike isn’t stock and how does that alter the way that a closed loop system works.?

As I said the stock maps are generally rich. At the top end, (High rpm, wide throttle opening .) they are generally sloppy rich, mainly because the designers know that just about the first thing Harry Hometune is going to do is stick pod filters and stupid noisy pipes on it and as a consequence they fling a lot of fuel at it to stop them melting pistons. They just wear rings out instead!

I reiterate, if your engine has steps in its power delivery it is tuned and mapped sub-optimally. The causes for that may or may not be map related. They might be the result of poorly thought out modifications to any part of the motor from inlet tract to exhaust length and dimensions. 
 

Tuning an engine, any engine, requires looking at it holistically and having a grasp of physics and fluid dynamics. It’s not simply a matter of applying a set of general principles dreamt up in a different age or different technologies. A motor is an air pump but the factors governing its ability to pump most efficiently vary. 

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I suspect the deleting of the airbox has more to do with the "steps" in the power curve, not the mapping. And while for most people removing the airbox looses too much power where they want it to put what power it does add elsewhere, if that sort of power delivery works for you I say go for it and have fun.

I fully understand how a more peaky power delivery can be fun. One of the most enjoyable street bikes I have ever had was an FZR400. It wasn't until you hit 10,000 rpms that things got seriously entertaining. But once there it was quite entertaining. While a Guzzi lump with the air box and proper exhaust can deliver an incredibly wide spread of power, take that air box away and the spread of power becomes less wide and more focused on certain rpms, depending on intake tract length and cam profile. While that may not be something everyone wants, I can see how it could be fun. Most people focus on the total area under the curve, generally for streetbikes that is what is considered optimal. But sometimes it is worth sacrificing some of the area under the curve to make things a little more aggressive.

Sometimes people need to relax. It isn't always about what gives the best curve on a dyno. Sometimes it is just about what makes it fun.

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6 hours ago, GuzziMoto said:

 One of the most enjoyable street bikes I have ever had was an FZR400. It wasn't until you hit 10,000 rpms that things got seriously entertaining. But once there it was quite entertaining.

Reminds me of my GSXR750, last year edition of the old oil burners.  Just after I picked it up new from the dealer, I took it on a freeway on ramp, turning about 4000 rpm from tootling the downtown streets.  I whacked the throttle full open ... and damn near got my ass run over.  The bike didn't cough, didn't stumble, just didn't make any appreciable horsepower.  I survived that event and quickly learned to bang two down shifts and spin it to 10,000 rpm and beyond to make decent beans (it red lined at 13,500, reminded me of a Cox Thimbledrome model airplane engine). 

I traded that bike in on my last dirt bike, a first year edition Yamaha WR250F, a five valver with compression impossible to kick over without benefit of the compression relief.  Unfortunately, this new model trail bike had the motocross tuned engine.  Not much HP below five figures.  It was okay for laid back trail riding, get it up to 8-9K and shift, no prob.  But if you wanted to go fast, you didn't shift, just cracked the throttle wide open.  The real horsepower was between nine and fourteen thousand rpm.  But it wasn't very controllable.  It was like the old Amal GP carb, as soon as you let the throttle off full open, it fell on its face.  WFO or nothing.

This is why I appreciate the V11 with a nice, wide, usable power band that you don't have to wrap to the moon to get moving.  Maybe I'm just old and lazy now, whatever.  No more five digit power bands for me.  :oldgit:

 

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10 hours ago, GuzziMoto said:

I suspect the deleting of the airbox has more to do with the "steps" in the power curve, not the mapping. And while for most people removing the airbox looses too much power where they want it to put what power it does add elsewhere, if that sort of power delivery works for you I say go for it and have fun.

I fully understand how a more peaky power delivery can be fun. One of the most enjoyable street bikes I have ever had was an FZR400. It wasn't until you hit 10,000 rpms that things got seriously entertaining. But once there it was quite entertaining. While a Guzzi lump with the air box and proper exhaust can deliver an incredibly wide spread of power, take that air box away and the spread of power becomes less wide and more focused on certain rpms, depending on intake tract length and cam profile. While that may not be something everyone wants, I can see how it could be fun. Most people focus on the total area under the curve, generally for streetbikes that is what is considered optimal. But sometimes it is worth sacrificing some of the area under the curve to make things a little more aggressive.

Sometimes people need to relax. It isn't always about what gives the best curve on a dyno. Sometimes it is just about what makes it fun.

I've never found a situation where a peaky or top end weighted power band was of any utility or fun. It was at best just a consequence of obtaining the required power. As ICE technology became refined the ability to get decent torque over a wider rpm range and maintain the top end power improved engines became more useful. 

Even at the elite level of road racing these days it's all about making the torque delivery to the rear tyre controllable whether mechanically or electronically. A V11 engine isn't in fact a very flexible engine to start with as its spread of torque and power is quite narrow. From 3500-4750 rpm the torque curve falls flat on its face and its all done by 5500 rpm. Compared to an old GSXR1100 and although its 12 Ft/lbs less peak torque its smooth and straight climb from 2500 to 9000 rpm. So a lumpy 3000 rpm curve compared to a straight smooth 6500 rpm torque spread. Which ones more flexible? In other words the std V11 engine is already a narrow torque band engine compared to its UJM contemporary. Its a sharp but brief torque hit with holes in it. Combine that with a heavy flywheel and people seem to think its got a wide spread of torque and is "flexible", it's not. Anything you do to a V11 engine that doesn't help fill in the std midrange hole is just silly stuff in my view.

Ciao 

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13 hours ago, Lucky Phil said:

I've never found a situation where a peaky or top end weighted power band was of any utility or fun. It was at best just a consequence of obtaining the required power. As ICE technology became refined the ability to get decent torque over a wider rpm range and maintain the top end power improved engines became more useful. 

Even at the elite level of road racing these days it's all about making the torque delivery to the rear tyre controllable whether mechanically or electronically. A V11 engine isn't in fact a very flexible engine to start with as its spread of torque and power is quite narrow. From 3500-4750 rpm the torque curve falls flat on its face and its all done by 5500 rpm. Compared to an old GSXR1100 and although its 12 Ft/lbs less peak torque its smooth and straight climb from 2500 to 9000 rpm. So a lumpy 3000 rpm curve compared to a straight smooth 6500 rpm torque spread. Which ones more flexible? In other words the std V11 engine is already a narrow torque band engine compared to its UJM contemporary. Its a sharp but brief torque hit with holes in it. Combine that with a heavy flywheel and people seem to think its got a wide spread of torque and is "flexible", it's not. Anything you do to a V11 engine that doesn't help fill in the std midrange hole is just silly stuff in my view.

Ciao 

You have a different way of looking at this than I do.

That you have never enjoyed a peaky powerplant is your opinion. But your opinion on that doesn't mean someone else who does enjoy a peaky power plant is wrong.

As to the width of the V11's power, ours delivers very usable power from 3,000 rpms to over 7,000 rpms. That is, it delivers good power for around 2/3's of it rpm range (looking at it as from idle (around 1200 rpms) to redline. Compared to the previously mentioned FZR 400, which delivers good power for around 1/3 of its rpm range. You are looking at it as "how many rpms does it make good power in. And that is one aspect. But another, possibly better metric is to look at it by how much of its available rpms does it make good power in. And I don't know about your V11, but the wife's V11 makes good power from 3,000 rpm to over 7,000 rpm.

A great example of it is way back when I was riding the wife's V11 with a couple friends. One was on a new R1 (new at the time, this was probably 20 years ago when the R1 was new), he was a buddy I roadraced with. After a while he said to me he was stunned at how badly the V11 would pull him out of corners. His R1 had way more power than the V11 had, but to use that power he had to really rev the engine. Where as the V11 seemd to pull hard out of the corners without effort, no extra revs required. Could an R1 go faster than a V11? Sure. But not without bringing the revs up.

I have ridden a number of small displacement streetbikes, bikes like the Ninja 250 and Eliminator 250, the aforementioned FZR 400, and others. They were all peaky, and they were all good fun to ride, especially on a twisty road.

And yeah, when you have 200+ hp you need to worry about making it usable. A V11 doesn't have that problem.

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