Honda Power Unit Hardware & Software

All that has to do with the power train, gearbox, clutch, fuels and lubricants, etc. Generally the mechanical side of Formula One.
Tommy Cookers
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Re: Honda Power Unit Hardware & Software

Post by Tommy Cookers » Mon Oct 14, 2019 10:13 pm

Nonserviam85 wrote:
Mon Oct 14, 2019 4:55 pm
A....The guiding philosophy in a big bang engine, is that the "relaxation time" is long enough between the time when the engine is applying force to the road (the first 90 or so degrees of crankshaft rotation, or ignition) and the time when it's going through the non-force applying functions of a four stroke engine (exhaust intake and compression), that the remaining 630 degrees allow the tyre to re-grip, such that if too much force is applied during that 90 degrees of ignition and the tyre begins to slide, there is still 630 degrees of non force application. This provides a buffer for the rider to not be sent over the handlebars

B ....There is the other argument for using the big bang engine. It is the idea that a big bang configuration is able to somehow improve the quality of the feedback that a rider receives from the rear tyre, so that they can better understand what the rear tyre is saying to them. .....

C ....All the manufacturers are using Big Bangs or Low Bangs (or even twin pulses) at this moment except Honda .....
A is saying that all 4 cylinders fire simultaneously ie the 4 cylinder engine behaves like a 1 cylinder engine
that's complete rubbish - there's no such engine
(yes the Yankee Ossa and one similar type of Husqvarna engine were simultaneous-firing 2 cylinder 2 strokes)

B is the M1/R1 justification put out by M1 program manager Furasawa (an electronics engineer) after his retirement
but of course the M1 (he says) is not BB - and (he says) they tried a BB version of the M1 and it was no good
(a BB M1 would be like the 270 deg plot shown in PZ's post yesterday)

C is a catch-all statement that seems to defy B

there has never been any paper presented to eg the SAE that covers or even mentions the points that I quote as A B and C

anyway the prime need in F1 is for a firing pattern best suited to maximising power to the turbine

Nonserviam85
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Re: Honda Power Unit Hardware & Software

Post by Nonserviam85 » Mon Oct 14, 2019 11:02 pm

Tommy Cookers wrote:
Mon Oct 14, 2019 10:13 pm


there has never been any paper presented to eg the SAE that covers or even mentions the points that I quote as A B and C

anyway the prime need in F1 is for a firing pattern best suited to maximising power to the turbine
So have you seen a SAE paper from Mercedes describing the benefit of the split turbine philosophy for example?

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Re: Honda Power Unit Hardware & Software

Post by Mudflap » Mon Oct 14, 2019 11:53 pm

Firing order is chosen to maximise output - see the Renault V10 paper. In many instances this has negative effects on the torsional vibrations but performance always takes precedence.

A 90 degree 3 throw crank engine will always have an inherent uneven firing order alternating between 90 deg and 150 deg CA intervals. The engine essentially behaves like 2 even firing inline 3 engines firing 90 degrees out of phase. It's one of the main reasons the plenums are kept separate - the pressure pulses are evenly spaced within each plenum.

The driveline of an F1 car is very compliant and as such it serves as a very good isolator between engine and wheel. Whatever torsional signature the engine has it is unlikely to be transmitted all the way down to the tire.

Finally, the fact that the engine is not firing evenly means its primary excitation is half the frequency of an even firing engine (1.5 order vs 3rd order respectively) so it is doing a bit of big banging but this is just a characteristic of the mandated engine configuration rather than something actively pursued by designers.

For reference an even firing v8 at 18000 rpm produces a 1200 hz torsional excitation while a 15000 rpm uneven firing v6 only manages 375 hz. If anything, the current engines risk reaching low enough frequencies that could excite the driveline with negative consequences on tire behaviour.
See Honda's oscillations issues caused by either upshift (and associated rpm drop) or launch (rpm drop due to bog down).

I would say if anything, artificially decreasing excitation frequency has the potential to make matters worse.
How much TQ does it make though?

Nonserviam85
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Re: Honda Power Unit Hardware & Software

Post by Nonserviam85 » Tue Oct 15, 2019 1:16 am

rscsr wrote:
Mon Oct 14, 2019 5:07 pm
Nonserviam85 wrote:
Mon Oct 14, 2019 4:55 pm
Tommy Cookers wrote:
Sat Oct 12, 2019 10:19 pm

each of these sentences above is wrong

anyway it was the 'screamer' NSR500 that won almost all the races when the 'big-bang' NSR500 almost never won
probably throttling off behaviour was the biggest effect of weird firing intervals (Mr Doohan hated the BB)
since 'slipper clutches' this aspect became irrelevant

regarding the M1 and R1 (supposed poster boys of BB) ...
according to the M1 boss Mr Furasawa they weren't BB
(yes he tried a BB version of the M1 crank)

search for crossplane in the 2 stroke thread (posts around Nov 2016)
or big bang of course
Honda changed to Screamer in 1997 so they were successful with the BB as well. When Honda switched the NSR500 to a screamer in 1997, riders we're throwing themselves off all the time, only the skill of the rider could compensate, this is why Mick Doohan won an incredible 12 of 15 races that year.

The guiding philosophy in a big bang engine, is that the "relaxation time" is long enough between the time when the engine is applying force to the road (the first 90 or so degrees of crankshaft rotation, or ignition) and the time when it's going through the non-force applying functions of a four stroke engine (exhaust intake and compression), that the remaining 630 degrees allow the tyre to re-grip, such that if too much force is applied during that 90 degrees of ignition and the tyre begins to slide, there is still 630 degrees of non force application. This provides a buffer for the rider to not be sent over the handlebars

There is the other argument for using the big bang engine. It is the idea that a big bang configuration is able to somehow improve the quality of the feedback that a rider receives from the rear tyre, so that they can better understand what the rear tyre is saying to them. The philosophy is that with a big bang you can apply some sort of input, such as the application of throttle to a tyre, and be given in return a useable amount of time to determine what that input has done to affect the motorcycle. With a screamer engine, the input is constant and permanent, there is no time to "hear" anything other than the input signal, you never get the chance to "hear" the feedback signal.

All the manufacturers are using Big Bangs or Low Bangs (or even twin pulses) at this moment except Honda, it is MM talent who is able to tame the motorcycle and win, every other driver complains about how difficult the Honda bike is. This is similar to what happened in 97 when Honda used screamers first, Doohan's talent helped them win.
please show me some sources to your claims. I couldn't find anything why a BB might be better. At least nothing scientific.
The whole motogp grid now use a BB variant, isn’t this enough proof? I have to admit I was wrong even Honda reverted to a BB configuration in 2017.

https://www.motorsport.com/motogp/news/ ... 63/904663/

https://www.google.co.uk/amp/s/www.moto ... 2018%3famp

You might not believe me but wouldn’t you believe MM chief engineer?

rscsr
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Re: Honda Power Unit Hardware & Software

Post by rscsr » Tue Oct 15, 2019 5:37 am

Nonserviam85 wrote:
Tue Oct 15, 2019 1:16 am
rscsr wrote:
Mon Oct 14, 2019 5:07 pm
Nonserviam85 wrote:
Mon Oct 14, 2019 4:55 pm


Honda changed to Screamer in 1997 so they were successful with the BB as well. When Honda switched the NSR500 to a screamer in 1997, riders we're throwing themselves off all the time, only the skill of the rider could compensate, this is why Mick Doohan won an incredible 12 of 15 races that year.

The guiding philosophy in a big bang engine, is that the "relaxation time" is long enough between the time when the engine is applying force to the road (the first 90 or so degrees of crankshaft rotation, or ignition) and the time when it's going through the non-force applying functions of a four stroke engine (exhaust intake and compression), that the remaining 630 degrees allow the tyre to re-grip, such that if too much force is applied during that 90 degrees of ignition and the tyre begins to slide, there is still 630 degrees of non force application. This provides a buffer for the rider to not be sent over the handlebars

There is the other argument for using the big bang engine. It is the idea that a big bang configuration is able to somehow improve the quality of the feedback that a rider receives from the rear tyre, so that they can better understand what the rear tyre is saying to them. The philosophy is that with a big bang you can apply some sort of input, such as the application of throttle to a tyre, and be given in return a useable amount of time to determine what that input has done to affect the motorcycle. With a screamer engine, the input is constant and permanent, there is no time to "hear" anything other than the input signal, you never get the chance to "hear" the feedback signal.

All the manufacturers are using Big Bangs or Low Bangs (or even twin pulses) at this moment except Honda, it is MM talent who is able to tame the motorcycle and win, every other driver complains about how difficult the Honda bike is. This is similar to what happened in 97 when Honda used screamers first, Doohan's talent helped them win.
please show me some sources to your claims. I couldn't find anything why a BB might be better. At least nothing scientific.
The whole motogp grid now use a BB variant, isn’t this enough proof? I have to admit I was wrong even Honda reverted to a BB configuration in 2017.

https://www.motorsport.com/motogp/news/ ... 63/904663/

https://www.google.co.uk/amp/s/www.moto ... 2018%3famp

You might not believe me but wouldn’t you believe MM chief engineer?
I know that. And I want to know why.

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Re: Honda Power Unit Hardware & Software

Post by hollus » Tue Oct 15, 2019 10:24 am

Big-bang in motorbikes... make a thread for it?
F1 related stuff here, please.
It is not white, it is not black, it is probably gray.

Tommy Cookers
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Re: Honda Power Unit Hardware & Software

Post by Tommy Cookers » Tue Oct 15, 2019 11:33 am

SUGGESTION ...
maybe Big Bang in Motorcycles could be continued in the existing '2 stroke thread (with occasional F1 relevance)' ?
because there's a lot of motorcycle stuff in it including serious Big Bang stuff

and
Mudflap wrote:
Mon Oct 14, 2019 11:53 pm
....The driveline of an F1 car is very compliant and as such it serves as a very good isolator between engine and wheel. Whatever torsional signature the engine has it is unlikely to be transmitted all the way down to the tire.
Finally, the fact that the engine is not firing evenly means its primary excitation is half the frequency of an even firing engine (1.5 order vs 3rd order respectively) so it is doing a bit of big banging but this is just a characteristic of the mandated engine configuration rather than something actively pursued by designers.
For reference an even firing v8 at 18000 rpm produces a 1200 hz torsional excitation while a 15000 rpm uneven firing v6 only manages 375 hz. If anything, the current engines risk reaching low enough frequencies that could excite the driveline with negative consequences on tire behaviour...
...I would say if anything, artificially decreasing excitation frequency has the potential to make matters worse.
just saying what wanders across my brainspace ....

wouldn't the 15000 rpm u/f V6 be torsionally exciting at 450 Hz ?

in principle torsional excitation comes from both 'power moments' and from inertial moments
but a crossplane cranked inline 4 (ie the Yamaha M1 and R1) largely cancels the inertial moments
as does a V2, V4, V6, V8, V10, etc if it has a V angle close to 90 deg
(inertial moments will be at 2x engine frequency)

in practice the crankshaft damper responds to variations in rotational speed regardless of whether they are from ....
power moments (+ any inertial moments) - causing relatively large variations in rotational speed (but safe to crankshaft)
torsional oscillation within the crankshaft - causing relatively small variations in rotational speed (but unsafe to crankshaft)

so doesn't an engine need its crankshaft damper to be effective only at frequencies well above maximum crankshaft rpm ?
ie the crankshaft's natural torsional frequency should be much higher than maximum rpm 'frequency' ?
(otherwise the damper might get beaten to death on its first day)
Last edited by Tommy Cookers on Tue Oct 15, 2019 2:23 pm, edited 1 time in total.

Nonserviam85
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Re: Honda Power Unit Hardware & Software

Post by Nonserviam85 » Tue Oct 15, 2019 1:52 pm

rscsr wrote:
Tue Oct 15, 2019 5:37 am
Nonserviam85 wrote:
Tue Oct 15, 2019 1:16 am
rscsr wrote:
Mon Oct 14, 2019 5:07 pm

please show me some sources to your claims. I couldn't find anything why a BB might be better. At least nothing scientific.
The whole motogp grid now use a BB variant, isn’t this enough proof? I have to admit I was wrong even Honda reverted to a BB configuration in 2017.

https://www.motorsport.com/motogp/news/ ... 63/904663/

https://www.google.co.uk/amp/s/www.moto ... 2018%3famp

You might not believe me but wouldn’t you believe MM chief engineer?
I know that. And I want to know why.
Ok, I will try to find Mr Masao Furusawa's presentation "What is a Big Bang". His area of expertise was Harmonics and while working in the 800cc Yamaha M1 (2007) to my knowledge, he was the only one who tried to tackle the issue analytically. In short he didn't agree to the tyre contact patch relaxation theory, he proposed that the BB engines offer better balance between Combustion Torque and Inertia Torque in high revving MotoGP bikes. This is over 10 years old and I need to dig a lot to find. However not everyone in the Paddock agreed with his views and the lack of hard data makes this difficult to settle.

I also agree this is off-topic, mods please free to transfer the posts to the relevant topic. :D

rscsr
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Re: Honda Power Unit Hardware & Software

Post by rscsr » Tue Oct 15, 2019 2:28 pm

Nonserviam85 wrote:
Tue Oct 15, 2019 1:52 pm
rscsr wrote:
Tue Oct 15, 2019 5:37 am
Nonserviam85 wrote:
Tue Oct 15, 2019 1:16 am


The whole motogp grid now use a BB variant, isn’t this enough proof? I have to admit I was wrong even Honda reverted to a BB configuration in 2017.

https://www.motorsport.com/motogp/news/ ... 63/904663/

https://www.google.co.uk/amp/s/www.moto ... 2018%3famp

You might not believe me but wouldn’t you believe MM chief engineer?
I know that. And I want to know why.
Ok, I will try to find Mr Masao Furusawa's presentation "What is a Big Bang". His area of expertise was Harmonics and while working in the 800cc Yamaha M1 (2007) to my knowledge, he was the only one who tried to tackle the issue analytically. In short he didn't agree to the tyre contact patch relaxation theory, he proposed that the BB engines offer better balance between Combustion Torque and Inertia Torque in high revving MotoGP bikes. This is over 10 years old and I need to dig a lot to find. However not everyone in the Paddock agreed with his views and the lack of hard data makes this difficult to settle.

I also agree this is off-topic, mods please free to transfer the posts to the relevant topic. :D
I also don't think that the relaxation theory is correct. But many thanks in advance.

Mudflap
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Re: Honda Power Unit Hardware & Software

Post by Mudflap » Tue Oct 15, 2019 10:09 pm

Tommy Cookers wrote:
Tue Oct 15, 2019 11:33 am

just saying what wanders across my brainspace ....

wouldn't the 15000 rpm u/f V6 be torsionally exciting at 450 Hz ?

in principle torsional excitation comes from both 'power moments' and from inertial moments
but a crossplane cranked inline 4 (ie the Yamaha M1 and R1) largely cancels the inertial moments
as does a V2, V4, V6, V8, V10, etc if it has a V angle close to 90 deg
(inertial moments will be at 2x engine frequency)

in practice the crankshaft damper responds to variations in rotational speed regardless of whether they are from ....
power moments (+ any inertial moments) - causing relatively large variations in rotational speed (but safe to crankshaft)
torsional oscillation within the crankshaft - causing relatively small variations in rotational speed (but unsafe to crankshaft)

so doesn't an engine need its crankshaft damper to be effective only at frequencies well above maximum crankshaft rpm ?
ie the crankshaft's natural torsional frequency should be much higher than maximum rpm 'frequency' ?
(otherwise the damper might get beaten to death on its first day)
The frequency is given by the order number x rpm / 60. Since the firing order for an uneven firing v6 is 1.5, the frequency at 15000 RPM is 375 hz. For even firing the order would be 3 and the frequency 750 hz.

Some good explanations for torsional excitations produced by an uneven firing V6 can be found here:
http://www.epi-eng.com/piston_engine_te ... ngines.htm

Note that the 2.4 th order is a typo - it's meant to say 2.5th

I agree that there will always be a 2x inertial excitation but this is always small compared to the excitation produced by the firing frequency. The 1.5 order is produced by what the author calls adjacent-pulse coupling - which is just a way of saying that closely spaced firing peaks (90° apart in this particular case) combine into a single peak such that over an engine cycle (2 revolutions) there are 3 big peaks rather than 6 distinct peaks in the case of an even firing 6 cylinder engine. The 3 pulses over 2 revolutions are what produce the 1.5x excitation.

The implication is that the excitation frequency is relatively low yet the amplitudes are high. A short V6 crank will have a high enough torsional natural frequency to avoid 1.5th order resonances yet it would still be susceptible to higher order lower energy excitations. However, when viewed as a whole, the cranktrain + driveline system will have low frequency modes due to the presence of compliant elements (input shafts, quill shafts, flexible couplings, etc).

The crankshaft should behave as a rigid body when these modes are excited ie. the node (point of 0 displacement) where the dynamic torques are highest must occur outside of the crankshaft.

For example in the V8/V10 era it was common practice to move the clutch in the gearbox and have it connected to the crank with a compliant shaft. This raised the natural frequency of the crankshaft and caused the node to be on the clutch shaft. Since this shaft only experiences torsional loads (unlike the crankshaft which is loaded in both torsion and bending) it is more suitable to deal with the shear stresses caused by high dynamic torques.

The entire driveline can have several modes with excitations at several orders across a speed range of close to 10000 RPM and it is only practical to avoid the most damaging of these (with the worst one being the firing order at peak torque RPM). For everything else, dampers are employed to reduce the response.

So to answer you question - the damper needs to be effective wherever there is a resonance. For multiple resonances, the viscous and friction dampers work over a range of frequencies, for a single resonance a tuned mass damper is sufficient and to reduce the amplitudes of an entire order the pendulum type absorber can be used.
How much TQ does it make though?

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Re: Honda Power Unit Hardware & Software

Post by Tommy Cookers » Wed Oct 16, 2019 9:48 am

Mudflap wrote:
Tue Oct 15, 2019 10:09 pm
....I agree that there will always be a 2x inertial excitation but this is always small compared to the excitation produced by the firing frequency. ....
I thank you for your post ....

but Furusawa said ....
(of a conventional NA inline 4 at race rpm) that the inertial excitation is greater than the firing excitation
then using a crossplane crank (Yamaha M1) eliminated the inertial excitation and helped the rider to find the traction limit
imo the crossplane crank makes the M1 excitation the same as the Moto GP V4's

of course the conventional inline 4 inertial excitation is no different to the traditional eg an inline twin's or a single's

btw
in the 1970s-80s etc millions of (GM. Honda and PRV) road cars had 90 deg 'true' V6 engines ie 3 crank throws & uneven firing

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Re: Honda Power Unit Hardware & Software

Post by Mudflap » Wed Oct 16, 2019 11:07 am

Tommy Cookers wrote:
Wed Oct 16, 2019 9:48 am
Mudflap wrote:
Tue Oct 15, 2019 10:09 pm
....I agree that there will always be a 2x inertial excitation but this is always small compared to the excitation produced by the firing frequency. ....
I thank you for your post ....

but Furusawa said ....
(of a conventional NA inline 4 at race rpm) that the inertial excitation is greater than the firing excitation
then using a crossplane crank (Yamaha M1) eliminated the inertial excitation and helped the rider to find the traction limit
Maybe, I can see that happening in a very specific context - high speed low load - when the cylinder pressures are very low and inertial loads at their highest.
How much TQ does it make though?

Nonserviam85
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Re: Honda Power Unit Hardware & Software

Post by Nonserviam85 » Wed Oct 16, 2019 4:53 pm

Tommy Cookers wrote:
Wed Oct 16, 2019 9:48 am
Mudflap wrote:
Tue Oct 15, 2019 10:09 pm
....I agree that there will always be a 2x inertial excitation but this is always small compared to the excitation produced by the firing frequency. ....
I thank you for your post ....

but Furusawa said ....
(of a conventional NA inline 4 at race rpm) that the inertial excitation is greater than the firing excitation
then using a crossplane crank (Yamaha M1) eliminated the inertial excitation and helped the rider to find the traction limit
imo the crossplane crank makes the M1 excitation the same as the Moto GP V4's

of course the conventional inline 4 inertial excitation is no different to the traditional eg an inline twin's or a single's

btw
in the 1970s-80s etc millions of (GM. Honda and PRV) road cars had 90 deg 'true' V6 engines ie 3 crank throws & uneven firing
What Furusawa said:

‘What is Big Bang?’ Furusawa’s area of expertise is harmonics, so perhaps he chose to use the analogy of signal-to-noise ratio to explain his theory:

Noise is always present, what you want is a strong enough signal to render it irrelevant. So what is signal and what is noise in the context of a motorcycle engine? This is best explained by thinking about that word ‘connection’ you keep on hearing riders use in testing. This is shorthand for the connection between the throttle and the rear tire. In an ideal world, opening the throttle by 10% would deliver 10% of available power (actually torque, but never mind) to the rear tire. Life is rarely this convenient or simple, and racing engines certainly aren’t.

Modern electronics should be able to provide the linear throttle response riders crave; a high signal-to-noise ratio. And our research suggests is that that is what you do get—up to a critical rev level where the signal is severely distorted by ‘noise’. The question is, what is this interference? This is ‘inertia torque’, that is the torque due to the motion of the heavy moving parts in the engine—crankshaft, con rods and pistons. This is totally separate from the torque generated by the combustion process. At low revs, the level of interference from the rotating mass is insignificant, but around 12,000rpm it starts to become greater than combustion torque and by around 16,000 is double. This is counter-intuitive because you would assume, with a conventional 180-degree crank, that everything would balance out. Not so, as you discover when you look more deeply at the direction in which torque is exerted at different points of a crank’s rotation.

Combustion torque is easy to understand: it’s produced by ignition of the fuel/air mixture. Inertia torque is much trickier to define and understand. Let’s try. Forget combustion and just consider the piston and con rod travelling up the bore. At BDC the piston, con rod and crank pin are in line and no torque can be applied to the crankshaft (in fact at top and bottom dead centres, the con rod is momentarily stationary and vertical). Now move through 90 degrees. The big end of the con rod together with the piston is moving quickly with lots of energy and is about to decelerate to a halt at TDC. That energy of motion (kinetic energy) has to go somewhere, and the only place it can go is into the crankshaft. So inertia torque is positive in that it is applied in the direction of rotation of the crank. On the down stroke, the converse is true. The lower part of the con rod together with the piston has to be rapidly accelerated from rest at TDC to a high velocity, which requires an input of energy. That removes energy from the crankshaft so here inertia torque acts against the direction of rotation.

Without doing the math, you can see how this variation of torque over each revolution might produce some small variations in the torque seen by the tire contact patch. On your 180-crank, four-cylinder road bike, you won’t notice the effect because you don’t use high enough revs, but as this inertia torque is proportional to rpm squared, you can see how a 17,000rpm MotoGP engine might have problems. At those sort of engine speeds, the ‘noise’ of the inertia torque is ‘louder’ than the ‘signal’ of the combustion torque. The rider’s connection with what’s happening at the rear tire’s contact patch is lost both with the throttle open and with it closed.
Thanks to GPS and Yamaha's electronics package, the M1 not only knew what gear it was in but which corner it was in. Very helpful data in setting up the bike.

The cure is equally counter-intuitive; an irregular firing pattern, 90- degree crankshaft. The conventional 180 crank has its two outer pistons at TDC while the centre pair are at BDC. Leave cylinders number one and three as they are then move two and four through 90 degrees in opposite directions and you have the 90-degree crank with one piston coming to TDC every 90 degrees of crank rotation. Yamaha tried firing all four cylinders in one revolution and compared the result to the more conventional firing order of two cylinder firing at a 270-degree interval in the first revolution of the crank and the other two firing just 90-degrees apart in the middle of the next revolution. The first surprise is that they sounded the same, the second is that there was no difference in traction. That effectively killed off the ‘big sneeze’ theory.

The mathematics say that inertia torque is reduced to almost zero before 10,000rpm and—crucially—to only about 3% of the 180-crank’s value at 15,000rpm. The experimental test to confirm the theory involved measuring rotational fluctuation of the rear wheel, a consequence of uneven torque delivery. With the 180 crank there are big torque spikes at all throttle openings, but with the highest peaks just as the rider gets on or off the throttle. The 90-degree crank shows no such behaviour, suggesting it would make getting into and out of corners a lot easier for the rider. Inertia torque (noise) is still there, it’s just at such a low level it doesn’t have a significant effect. Of course the first law of engineering says you never get something for nothing and an irregular firing order means vibration that may require a balance shaft or heavier components to tame, thus losing you part of what you’ve just gained.

These findings are of course all for in-line four-cylinder motors, but it’s easy to see how the 90-degree crankshaft can effectively mimic a V4—the back tire doesn’t know what direction the cylinders are pointing in! Is this an inherent advantage of the 90-degree V4 engine? Yamaha think not, and will continue with the in-line engine which they regard as enabling them to build a shorter and therefore more nimble machine. But they will have to use an irregular firing order crank.

Polite
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Re: Honda Power Unit Hardware & Software

Post by Polite » Wed Oct 16, 2019 5:08 pm

this from the old 2017 days.. (i remember also a video about the difference in shaking of the rear tyre for the screamer and the Bb engine here https://video.sky.it/sport/motogp/motog ... 381422.vid but no more available)

https://sport.sky.it/motogp/2017/11/17/ ... e-big-bang

this is common knowledge for motogp

hope it helps

Snorked
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Re: Honda Power Unit Hardware & Software

Post by Snorked » Fri Oct 18, 2019 1:26 pm

Needs a proper translation https://f1-gate.com/honda/f1_52742.html

Asaki talking at Suzuka - the way Google translated, Honda Jet helped Exxon with the fuel development?

What's jet fuel's chemical makeup?

Exxon said the fuel had never before used chemicals.