ESE's works engine tuner

[koba]

Right, Gotcha now.

[husaberg]

Yes 33 crankshaft hp. (if transmission losses are 16%)

The dyno measures rear wheel HP, the simulation simulates crankshaft HP there is some losses between the crank and what rolling roads measure at the rear wheel.

EngMod2T has a function where you hand enter the rear wheel dyno results and a correction factor and it prints out crank HP.

If the loss is truly 16% (at the moment 16 is a guesstimate) then my bike makes (Red line) about 33hp at the crank at 11,750 rpm, calculated (with guesstimate correction) from the 28.7 rear wheel hp as measured on the dyno. If the true losses are less than 16% then my engine is making less than 33 crank hp. I am just not sure what the real losses are yet.

Husaburg suggested to me that the dyno can be used to measure roll down resistance, I am not sure if thats the same as transmission loss but I will look into it, if it is then I can get a more accurate figure for the correction factor.

It turns out the Dynojet most likely can't .
But my line of thinking is it's is wrong to use a percentage figure for transmission loss based on the total HP.
Why say for instance TZeds bike makes 30hp at the rear wheel right if the transmission is estimated at say 10% that is 3 hp right.
Say the exact same model of bike without TZed tuning makes 15 hp so the loss would be 1.5hp but they have the exact same transmission?
Or if TZed finds a extra 10 hp to get to 40hp all of a sudden the same transmission absorbs 4 hp.
I am of course assuming the revs are all the same.

I think one that does calculate transmission losses is a FLA type dyno which has a eddy current dyno built into the flywheel to measure trans losses (According to John Robinson) although maybe the later dynojets do have one now? As the FLA is unlikely to be one around i guess or do a coast down test from a predetermined speed on flat ground no wind from a speed low enough to cancel out the air Resistance to a extent.If we know the weight of the bike and rider and the speeds and time we should be able to calculate the drag.
Of course you could get a alternator and see what it does take to run the bike down in neutral.

Added the Bud Aksland stuff as i tripped over it today.
The other one was in something i posted a week or so ago.

[wobbly]

I have visited Buds facility several times and its an amazing combination of super Hi Tech and super basic.
The main area is a big shipping container, with an office built outside one end, that sits in the yard of
a transport company.
The dyno is a Heenan eddy current using Depac software, inside the container.
Inside the "office" is a CNC anenometric flow visualiser, and a phone.
In the middle is a work area for grinding and pipe building, done by a Kiwi guy I cant remember his name - he was the crew chief
on Kocincis World Champ effort on the Yamaha, he took an instant dislike to me when I suggested that Little John had won the title despite the bike - as it
was easily the slowest in the field that year.

Re the dyno vs crank conversion.Many people have done this check on many setups, and the general consensus is that when using an inertia dyno on the sprocket
the difference is around 5 - 8% , and when using the rear wheel the difference is 12 to 16%.
These are the losses in the transmission/chain/tyre etc and seem to very similar % wise for a 125GP or a 1000 Superbike.
The BSL made 55 Hp per cylinder on the single with a crank driven dyno, at the same stage the triple in the bike read 142 at the rear wheel on a Dynojet - you do the math.
Really who gives a shit about the actual raw numbers generated, as long as the power curve shape and peak rpm point coincide between reality and the sim,then both the dyno and the sim can highlight if a change is better or worse.
The sims nowdays are a very good prediction tool, and way quicker/cheaper than the time spent cutting/shutting and dynoing for hours - unless of course you are being paid to do it..

[jasonu]

In the middle is a work area for grinding and pipe building, done by a Kiwi guy I cant remember his name - he was the crew chief
..

Possibly Norris Farrow???

[husaberg]

In the middle is a work area for grinding and pipe building, done by a Kiwi guy I cant remember his name - he was the crew chief
on Kocincis World Champ effort on the Yamaha, he took an instant dislike to me when I suggested that Little John had won the title despite the bike - as it was easily the slowest in the field that year.

Imagine being Kocinski Crew chief for a minute, sure the guy was mega talented, But WTF.
If you believe even 10% of was was written about him.
I read an interview done with him the other day crickey.
But the little bugger was magic to watch when on song.
Having said that it looks like he may have came out better than Gobert.
Plus why does that name seem so familiar Norris Farrow.
Did he campaign a modded RD350 in Europe in a TZ frame late 70's?

Also added a Apitec and GKN blub missing a page or two bugger maybe someone has the last ones.
What interested me was the squeeze form liners i am not even sure if they still make then as they aren't listed o the either web site.
The site is interesting in which the repairs are carried out i was wondering why i couldn't strip then tig up the whole cylinder and then machine it and re-coat it rather than a sleeve anyway.

Re coating i am not suggesting to send stuff oversea when we have a place in NZ.
Plus yes it would be easier to sleeve a cylinder.

http://www.poetonaptec.co.uk/default.htm
http://www.gkn.com/Pages/default.aspx

[TZ350]

I have become very interested in how to use a rolling road dyno properly and the inherant errors in inertia dynos used for measuring RWHP.

Comments I have found on the net.

Chassis dynos are great tuning aids but they only give a approximation of power output as some of the important variables are not accurately controlled. When all things are kept the same between runs and you get a tangible gain, it is a gain at least. How much, is open for discussion.

As most people know, there are power losses through the drivetrain so wheel hp is always lower than flywheel hp. Tire pressure and wheel alignment can have very significant effects on losses at the rollers. Tire pressures should be set the same between each test. Tire rolling resistance varies inversely with speed, another factor not taken into account or different inertial weight of different tyres and wheels, after all its an inertia dyno and changing the overall inertial weight that has to be spun up changes the HP reading.

An engine in a bike with lighter wheels will show more HP than the same engine in a bike with heavy wheels, One of our GP 125 engines in an RS125 chassis with its light wheels is easier to spin up then an FZR with its heavy wheels and so the engine in the RS chassis will show more HP on a rolling road dyno like our DynoJet.

Food for thought on dyno errors and dyno technique.

http://www.sdsefi.com/techdyno.htm
http://www.stahlheaders.com/Lit_Dyno%20info.htm
http://www.modified.com/editors/tech...ble/index.html
http://www.pumaracing.co.uk/POWER3.htm
http://www.pumaracing.co.uk/coastdwn.htm

And other mistakes you can make on a rolling road dyno ...

[Frits Overmars]

....it would be easier to sleeve a cylinder.

It would be even easier to bin it. And more sensible too, if you allow me to exaggerate just a bit.
Pressing in a sleeve is a no-no to begin with. Shrinking it in is better, but not good enough. Because no matter how tight you make that interference fit, during use oil will creep between cylinder and liner, starting at the exhaust port.
If you remove an old liner, you can see the charred remains of that oil all around the exhaust zone. So do not worry about the limited thermal conductivity of an iron liner; charred oil conducts heat infinitely worse.
Been there, done that. If there's anything that makes me experienced in the two-stroke field, it's the fact that I have personally committed every imaginable error. Racing an air-cooled 500 cc two-stroke single with a liner made me the fastest man in Holland - in drawing a clutch. Not even Lucky Luke could draw quicker .

[Frits Overmars]

Chassis dynos are great tuning aids but they only give a approximation of power output as some of the important variables are not accurately controlled... Tire pressure and wheel alignment can have very significant effects on losses at the rollers. Tire pressures should be set the same between each test.

Nothing is stopping you...

Another factor not taken into account or different inertial weight of different tyres and wheels, after all its an inertia dyno and changing the overall inertial weight that has to be spun up changes the HP reading. An engine in a bike with lighter wheels will show more HP than the same engine in a bike with heavy wheels.

Which makes an inertial dyno the perfect instrument for the development of competition engines. Because that is reality: a bike with lighter wheels will accelerate a bit faster.
Use a gearing on the dyno that gives you an acceleration time, equal to the time between gear shifts at the track. Then you will measure the engine the way it has to perform in real life. And the biggest advantage will be that the exhaust pipe will then heat up and cool down on the dyno just like it does on the track.

Earlier a lot has been said about measuring the losses between dyno and crankshaft. Forget about that; it's bullshit.
Losses caused by friction between gears are load-dependent. You cannot establish those by way of a coast-down measurement, because once the engine power is gone, the load is gone (or at least decimated).
If you want to be taken seriously, then only talk about horsepower you actually measured. If you want to talk crankshaft power, measure at the crankshaft.

[wobbly]

The old chestnut about heavy wheels and even worse the shitbox Harleys that have heavy flywheels "causing them "to make less power than a wee kart engine
on the rollers is a huge crock of shit.
The reality of the situation seems to escape some very clever people, alot of whom post on the net and sell dyno's as well - funny that.
At the end of the day the reason we put the kart - engine, bike, jetski, on the dyno is to achieve a "better " state of tune.
Once that is done, then taking the FZR and fitting light wheels will make it produce more "power " and it will be faster on the track because of this.
Changing from cast iron wheels, to carbon composite wheels is a "tuning" aid , just as much as a Wobbly pipe might be.
The rolling road will show this - the engine dyno wont.
Again as I keep saying - who gives a shit - if it makes more power on any dyno, no matter what the number is, it will be faster.

[husaberg]

It would be even easier to bin it. And more sensible too, if you allow me to exaggerate just a bit.
Pressing in a sleeve is a no-no to begin with. Shrinking it in is better, but not good enough. Because no matter how tight you make that interference fit, during use oil will creep between cylinder and liner, starting at the exhaust port.
If you remove an old liner, you can see the charred remains of that oil all around the exhaust zone. So do not worry about the limited thermal conductivity of an iron liner; charred oil conducts heat infinitely worse.
Been there, done that. If there's anything that makes me experienced in the two-stroke field, it's the fact that I have personally committed every imaginable error. Racing an air-cooled 500 cc two-stroke single with a liner made me the fastest man in Holland - in drawing a clutch. Not even Lucky Luke could draw quicker .

Noted Frits. I know you are on the money there.
But the problem i face is Honda were not aware that i wanted a 50mm bore and not a 54mm bore they also cocked up the stroke a bit as well, Bloody Honda. I still do love them though. Its just they may not get lucky tonight that's all.

PS You never replied to the Aprilia Dellorto stuff. I checked it only mentioned "Macbeth" twice.Whoops forgot to blackout
Also when are the FOS cylinder going to be available in a 50mm bore?

The other bit Frits what i think TZ is trying to do is get the sim to match the Dyno.
To do that he needs to acturatly establish the crank HP. He want to get it as close as pos.

[TZ350]

If you want to be taken seriously, then only talk about horsepower you actually measured. If you want to talk crankshaft power, measure at the crankshaft. Or shut it.

Bit harsh but deserved I suppose because after all I did spell your name wrong....

Just for those experts that might find themselves frustrated with those of us learning this craft ..... this is our hobby and to be enjoyed.... If I want grumpyness I can go to work and be paid to enjoy it.

[Frits Overmars]

PS You never replied to the Aprilia Dellorto stuff.

They say the second thing to go is the memory, and I can't remember what the first thing was. Honestly Husaberg, I cannot recall that question. I either missed it or it was something I could not answer for one reason or another.

when are the FOS cylinders going to be available in a 50mm bore?

That may be quite a while. But the idea is so simple; build one yourself. In fact that would be much easier than building a conventional cylinder.
In a conventional jug you need five differently-shaped transfer ducts; in my system you need only one shape, six times. And you need one bridged exhaust duct, twice. Don't you love symmetry?

[Frits Overmars]

Bit harsh but deserved I suppose because after all I did spell your name wrong.... .

Don't worry about that spelling. I'm not one to hold a grudge over something so trivial. I try not to hold a grudge period; it would be a waste of energy.
Yes, it may have come over a bit harsh; I've expurgated it now. But it wasn't aimed at you personally. It's just that sometimes I get fed up with always that same BS of 'measuring' losses and then adding them, so spoiling a good measurement.

[TZ350]

Ok I got the chance tonight to find out what went wrong on the dyno last night.



Blown head gasket ("O" ring) as I suspected.



The piston has been just touching the head



The piston itself looked good and the ring was still free in the grove.



The culprit is the hand made gasket on the right, it compressed down to much, I expect its compressability allowed the combustion pressure to spit the "O" ring out. I replaced it with an alloy plate which should give a more reliable stack for setting the squish clearance and give something more solid for the head to pull up against.

[husaberg]

They say the second thing to go is the memory, and I can't remember what the first thing was. Honestly Husaberg, I cannot recall that question. I either missed it or it was something I could not answer for one reason or another. That may be quite a while. But the idea is so simple; build one yourself. In fact that would be much easier than building a conventional cylinder.
In a conventional jug you need five differently-shaped transfer ducts; in my system you need only one shape, six times. And you need one bridged exhaust duct, twice. Don't you love symmetry?

Yes i do love the idea so logical and elegant in afterthought for me Genius in forethought for you.But
I don't believe NZ has a foundry capable to doing that now, or that would be willing to do it as a one off.
Plus Wob has to eat.

Some more light able to be shed on this tasty little Italian Aprilia esp the semi active suspension. 1992

Another question was to do with the Dellorto carbs.
Were other carbs tried or were the Dellottos better suited to the Disk valve engine or were there other considerations.
Such as their Italianess or sponsorship (I see there is a sponsor sticker on the fairing) or just as case of sticking with what the team was familiar with.
One last thing was that you mentioned in the pit lane thread about the electric power-jet when did Aprilia implement this?. You also mentioned about a car solenoid or stepper motor. A Fiat Uno one why did you go to a Keihin part.

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