Does the ecu have enough timing advance to use 92 octane fuel

[mobilemike]

I realize Yamaha has recommended our bikes are suited for regular fuel. But does the ECU have a dynamic timing curve that is large enough to take advantage of 92 octane fuel? Timing is power and timing is fuel economy so If the engine were able to utilize more timing afforded by higher octane we could see better fuel range per gallon.

Knock sensors are no longer required to adjust dynamic timing and the area above the base timing curve can be quite large.

Is there any evidence Yamaha installed a large enough dynamic curve to the ECU to use it?

 

[Viper Pilot]

Your wasting your $$$$!

 

[ionbeam]

Yamaha has never made the spark timing map available. A very good guess for Gen I & Gen II engines is that the spark map is optimized for 89 octane and running anything more than that is a waste. I don't see it changing for the Gen III, but the electrical ignition has to be changed to accommodate the coil over plug system. If Yamaha wanted to squeeze more performance out of the engine I would expect it to start with revised cams. If Yamaha did in fact change anything to get more power or enhance the torque curve I would expect them to loudly brag about it

 

[Redfish Hunter]

Is there any evidence that they did not? Yamaha had to expect that there would be a wide range of fuels and fuel quality run through this machine. I am fairly certain they figured that into their program.

FWIW, Dad has run the "Premium" level fuel in his '07 since the day he got it. I have done the same with my '15. Down here, that is 93 octane. They are both running fine.

I will repeat an oft repeated saying of this forum: Ride More, Stress Less.

 

[Kelvininin]

Enough timing? I am assuming you are wondering of the FJR advances the timing for different fuels? No. There is nothing to tell the ECU that FJR is burning the higher octane fuel. You can add that flexibility with a Power Commander V, but I doubt it will buy you much if any additional power at the rear wheel. Advancing the timing will buy you a few ponies but nothing significant. IF you are going to add a PCV you may as well upgrade the exhaust as well.

 

[Road_Runner]

I would think you could advance the timing with a Power Commander. Hard to say if any gains could be realized w/o other changes (cams, higher compression, freer flowing intake/exhaust).

 

[El Toro Joe]

Why?

 

[Redfish Hunter]

Not sure the Power Commander affects the ignition timing. I think the PC-V affects the injectors. I know it plugs into the injector wiring but I do not recall it attaching to the ECU. Unless the ignition timing is affected by the fuel flow, I do not see it. Someone else may know better than me though.

Again, I do not see any need for a PC-V to tune the timing just to run a fuel with a higher octane rating. Pop and I have always run the highest octane fuel available and the results have always been good. I already know, it's a waste of money, it does nothing, we are stupid... Whatever. We have done well with our choices so far and my preference for the bike that I pay for is all that matters.

The bike will run fine on pretty much whatever grade of gasoline you wish to buy.

 

[ionbeam]

I would think you could advance the timing with a Power Commander. Hard to say if any gains could be realized w/o other changes (cams, higher compression, freer flowing intake/exhaust).

The Power Commander for the FJR only alters the fuel injection. Other makes and models allow the Power Commander to alter spark timing too.

[Drift]

To make more power you essentially need to move more fuel and air through the motor and if possible, increase the pressure in the combustion chamber. There are a lot of things that need to be altered to let this happen and they all need to be addressed as a system, tuning for increased volumetric efficiency.

[/Drift]

 

[Ignacio]

Watching closely and with personal interest to see how this thread hews to the specific and unique question of whether the ECU has a dynamic timing curve that is large enough to take advantage of 92 octane fuel and hoping it doesn't want to drift too far afield.

Thanks.

The Management

 

[Redfish Hunter]

Watching closely and with personal interest to see how this thread hews to the specific and unique question of whether the ECU has a dynamic timing curve that is large enough to take advantage of 92 octane fuel and hoping it doesn't want to drift too far afield.

Thanks.

The Management

And how can we absolutely know? We know the bike will still run, at least I know and I hope you folks trust me on this.

But what is the definition of advantage? Does this mean that the OP wants more HP, better acceleration, better fuel mileage? Or was he literally wanting to know if it will still run?

I sure as hell do not want this to drift into a fuel mileage thread but without a dyno run or specific quarter mile times, MPG may be the easiest yardstick we can use to judge "advantage". And there are just too many variables involved to make apples to apples comparisons with fuel mileage so how can we judge this?

 

[Road_Runner]

Why?

Because advancing the ignition timing and therefore the arrival of the spark only helps if the fuel/air mixture in the right amount is in the combustion chamber at the correct time. It may be that the spark is arriving as early as it can already based on the timing of the fuel/air and therefore the profile of the cams in the bike currently.

 

[mobilemike]

To answer several questions.

Most modern fuel timing systems, carborated and fuel injected have a two stage advance system . A fixed advance that is controlled by engine RPM and the throttle position sensor. And a secondary "Dynamic" system or area above the fixed system. It is the dynamic system I am musing about.

How the dynamic system work is;

As the engine in running with a set of parameters the dynamic portion of the system will begin to advance the timing until the ECU detects a stop in the rise of RPM or a drop in the RPM. The ECU does this action many times a second. The engine will achieve a maximum timing the fuel and conditions will allow.

It used to be older less intelligent systems used a knock sensor but those are being phased out as not accurate and quick enough.

Mercuriser has used this system in their Thunderbolt 5 timing system since the late 90s. It uses no knock sensors. All the timing sensing is done in the module.

A tuner is not necessary to advance the timing as the dynamic portion already exists. The manufactures use this portion to control engine damage from inferior grades of fuel.

 

[pista]

It used to be older less intelligent systems used a knock sensor but those are being phased out as not accurate and quick enough.

WOW!

Somebody needs to call GM and let them in on this because even a 2016 6.2L Supercharged Corvette engine uses knock sensors...

And for some odd reason, Porsche continues to use this antiquated system on their 2016 3.8L H6 turbo 911 as well.

And to stay on topic, I've no idea if the Yamaha ECU has a dynamic timing curve.

If I were to hazard a guess my answer would be no. Otherwise Yamaha would recommend 93 octane to allow the engine to take advantage of advanced timing.

 

[ionbeam]

The correct answer is -- there is no positive answer. The FJR1300 Technical Orientation Guide goes into a lot of detail about the major systems in the FJR but never mentions the ignition timing. None of the 3 Gens FSMs discuss the spark timing. Aftermarket engine controllers like the Power Commander do not manage the spark timing. Yamaha does not discuss the spark timing. I can make a pretty good educated guess at how the timing is managed but without something printed or a direct discussion with a Yamaha factory representative that definitively knows how the timing is managed it's all speculation.

That said, the entire engine management for the FJR is old school, straight forward, conventional and uninspired reliable. I can't imagine that Yamaha would go wild on just the spark timing with some risk of engine health and little gain. A bit more duration or advancing of the cam timing would do worlds more than spark timing.

 

[art miller]

Is there any evidence that they did not? Yamaha had to expect that there would be a wide range of fuels and fuel quality run through this machine. I am fairly certain they figured that into their program.
FWIW, Dad has run the "Premium" level fuel in his '07 since the day he got it. I have done the same with my '15. Down here, that is 93 octane. They are both running fine.

I will repeat an oft repeated saying of this forum: Ride More, Stress Less.

You are only pushing $$'s out the exhaust running 93 octane. It has been sufficiently documented when premium octane fuel is needed. Dr Bill Wattenburg, retired Professor Nuclear Engineering, UC Berkeley has stated numerous times octane is simply a means of regulating the rate fuel ignites. He suggests there is no need to use premium gas in any vehicle unless the manufacturer so advises. He also has stated most vehicles other than very high performance engines do not need premium gas. If the valves do not ping on acceleration you are not going to damage the engine. Ride more, save more, use regular octane gas!!!

 

[N4HHE]

I realize Yamaha has recommended our bikes are suited for regular fuel. But does the ECU have a dynamic timing curve that is large enough to take advantage of 92 octane fuel? Timing is power and timing is fuel economy so If the engine were able to utilize more timing afforded by higher octane we could see better fuel range per gallon.

Timing, compression, ECU, you are sweating the wrong details. Keep a logbook of fuel purchases and ride at least 5 tanks of 87 octane then follow with 5 more tanks of 93 octane then revert back to 87 again. Did 93 result in better MPG? If so did MPG fall off when you went back to 87? MPG is all that matters, how that MPG was produced is of no consequence.

Conducting that experiment I have never found higher octane gasoline of be of benefit greater than its cost. Then again my Husaberg really needs 91 octane else it knocks. Then again I work it harder than any self-respecting FJR is ridden.

 

[El Toro Joe]

Then again I work it harder than any self-respecting FJR is ridden.

You'd be surprised...

 

[Bounce]

Is there any evidence that they did not? Yamaha had to expect that there would be a wide range of fuels and fuel quality run through this machine. I am fairly certain they figured that into their program.
FWIW, Dad has run the "Premium" level fuel in his '07 since the day he got it. I have done the same with my '15. Down here, that is 93 octane. They are both running fine.

I will repeat an oft repeated saying of this forum: Ride More, Stress Less.

waste of money and not what octane is used for. No documentation that I know of has addressed how the timing is advanced or retarded within the whole of the system. Since it only deals with when the spark happens for working through pre-ignition; if you're not knocking, then you don't need higher octane. That question should be addressed first before gnawing on rationalizations for using an octane rating higher than that recommended by the engineers who designed the whole.