Fuel Injected Commando datalogging session

comnoz said:

marksterrtt said:

Can't wait to see this set up run, and I thought waiting for Christmas was hard. I missed how the fuel gets into the backbone Jim, is it just gravity feed from the tank? Mark

Click to expand...

There is vacuum operated pump that circulates the fuel between the backbone tube and the fuel tank.
Originally I tried gravity feed but the fuel in the backbone got too hot from engine heat and the high pressure pump would vaporlock. Jim

Click to expand...

Thanks Jim, yours is undoubtedly the most developed Commando in existence. Your answer to the stroke/bore question was interesting, would your displacement or a larger 360* twin be bearable, vibration wise, if it weren't for the isolastic mount system?..Mark

marksterrtt said:

comnoz said:

marksterrtt said:

Can't wait to see this set up run, and I thought waiting for Christmas was hard. I missed how the fuel gets into the backbone Jim, is it just gravity feed from the tank? Mark

Click to expand...

There is vacuum operated pump that circulates the fuel between the backbone tube and the fuel tank.
Originally I tried gravity feed but the fuel in the backbone got too hot from engine heat and the high pressure pump would vaporlock. Jim

Click to expand...

Thanks Jim, yours is undoubtedly the most developed Commando in existence. Your answer to the stroke/bore question was interesting, would your displacement or a larger 360* twin be bearable, vibration wise, if it weren't for the isolastic mount system?..Mark

Click to expand...

The bigger they get the more they will vibrate. I am sure my 914 would not be a pleasant long distance cruiser in a solid frame. Jim

The bike runs.
Shortly after starting it I realized the mixture was off and after it ran long enough to get out of the warmup stage it became very lean. Obviously the throttle body had affected the map signal enough that the ECU had learned and adjusted as well as it could to make up for it.

So what I did was continued to warm up the engine enough that I could enable autotuning and then began running the engine through all the rpm and load ranges to allow the O2 feedback to correct the VE table.

So you will be getting to see some brutal wide open full load testing through all rpm ranges instead of an easy ride.
After running for a bit the VE table was corrected enough that the bike was running well but it will take a couple more sessions or a good road trip to get it dialed perfectly.

My daughter took some video. When I enable the autotuning you will see the VE table with a floating dot showing what value is presently in use. Engine load is vertical travel and rpm is right to left. Wherever the dot passes an entry you can see the numbers change as the correction is made. Once all entries have been adjusted using the coarse setting then I can set the tuning for fine adjustments and run through all the cells again to get it right on the nose.

After the fast auto tuning is done the mixture as read by the O2 sensor will be compared to a mixture look-up table and the VE table will slowly be altered to maintain the desired mixture as you ride. These adjustments will be made in a temporary table but will be moved into the permanent table if the condition persists for a preset amount of time.

Here is the video- turn it up.

[video]http://youtu.be/l1ICT8S4gBg[/video]

Alrighty looks like you might be able to help program ignition timing launch control.

Jim, congratulations on your bike and your setup! Quite mind boggling I must say.

And now back to my two Amal 932 carbs... :mrgreen:

(Might need some adjustments by the way...) :roll:

Jim,

Well, I asked for "beller" and got it! Unbelievably nice dyno set-up and bike to match. The instrumentation and auto-tune are things of great beauty, where R & L EGT are quite disparate to begin with, but with a bit of driving come around quite nicely.

Have a couple questions about the set-up.

Cooling Fan - The cooling fan housing looks like a vintage jet engine. What is it, where did it come from, and how much air does it move (not looking for number just a general qualitative/intuitive assessment from you)?

Dyno Resistance - is the drum resistance fixed, ramped to drum speed, or what???? Eddy current resistance?

Engine Test Fixture - I know your dyno is fit with the ability to run either full chassis motorcycles or naked engines. Tell us a little about the fixture for running a naked engine, i.e., what sort of reduction is employed, assume there must be some sort of cush-drive, and what else goes into the set-up?

Jim,

That was fun to watch...although the warm up was kind of boring

This might seem like a stupid question, but why were the exhaust temps so different between each other at the beginning of the run and then evened out?

Also what's the difference between the fuel mixture gauges left and right? They seemed to be giving different readings.

It was cool to watch the tuning happening real time...amazing stuff.

Dennis

WZ507 said:

Jim,

Well, I asked for "beller" and got it! Unbelievably nice dyno set-up and bike to match. The instrumentation and auto-tune are things of great beauty, where R & L EGT are quite disparate to begin with, but with a bit of driving come around quite nicely.

Have a couple questions about the set-up.

Cooling Fan - The cooling fan housing looks like a vintage jet engine. What is it, where did it come from, and how much air does it move (not looking for number just a general qualitative/intuitive assessment from you)?

Dyno Resistance - is the drum resistance fixed, ramped to drum speed, or what???? Eddy current resistance?

Engine Test Fixture - I know your dyno is fit with the ability to run either full chassis motorcycles or naked engines. Tell us a little about the fixture for running a naked engine, i.e., what sort of reduction is employed, assume there must be some sort of cush-drive, and what else goes into the set-up?

Click to expand...

The cooling fan was originally used in the ductwork of a large building. It is powered by a 5 horse motor and puts out a very strong "breeze" The bike will run cooler on the dyno than it will down the road.

The dyno has a weighted drum that simulates a 700 lb bike and rider.
Added to that is an eddy currant brake. During the video I was running the brake with a foot pedal to load the engine.
Normally the brake would be controlled by the dyno computer and it can control ramping or hold a set speed for torque measurements.

The engine mount uses a common primary belt drive and clutch. A second belt runs from what would be the transmission mainshaft down to a pully on the end of the drum. The ratio comes out at about the same as if the engine was in a bike and the bike was in high gear. I don't recall the exact ratio off the top of my head. Jim

dennisgb said:

Jim,

That was fun to watch...although the warm up was kind of boring

This might seem like a stupid question, but why were the exhaust temps so different between each other at the beginning of the run and then evened out?

Also what's the difference between the fuel mixture gauges left and right? They seemed to be giving different readings.

It was cool to watch the tuning happening real time...amazing stuff.

Dennis

Click to expand...

The warm up was boring, that wasn't what I was planning on doing in the video.
Normally the bike would have run great from the time it was started and I would only have given it a very short warmup before I applied a load and turned up the throttle.
The exhaust gas temps were off because the engine was running so poorly.
I really don't know at this time why it seemed to affect one cylinder more than the other but I am wondering.
I do know that now that the engine mixture is close the exhaust temps are close also. Jim

And the difference in O2 readings were because the the readout on the temp screen was from the sensor in the exhaust extractor and the readout on the injection screen was from the O2 sensor in the exhaust pipe that is the feedback for the ECM. The feedback sensor is limited to a maximum of 16-1 ratio and was pegged until the mixture came into range.

The sensor in the exhaust extractor will read a mixture as lean as 26 to 1.

Unless the engine is running with no misfires the O2 sensor readings are meaningless. Just a couple misfires for any reason will cause the O2 sensor to peg out on the lean side due to the unburned oxygen passing through the cylinder. Jim

comnoz said:

And the difference in O2 readings were because the the readout on the temp screen was from the sensor in the exhaust extractor and the readout on the injection screen was from the O2 sensor in the exhaust pipe that is the feedback for the ECM. The feedback sensor is limited to a maximum of 16-1 ratio and was pegged until the mixture came into range.

The sensor in the exhaust extractor will read a mixture as lean as 26 to 1.

Unless the engine is running with no misfires the O2 sensor readings are meaningless. Just a couple misfires for any reason will cause the O2 sensor to peg out on the lean side due to the unburned oxygen passing through the cylinder. Jim

Click to expand...

Ah, makes sense now. That O2 sensor for the ECM is really different than what I am used to. It probably makes more sense once the mapping is corrected. The lean mixture on the other one made sense since the mapping had adjusted to the broken butterfly...this is really amazing stuff Jim. What you have there is something we all can envy. To be able to see pretty much everything that is happening real time is something I have never seen, particularly on a Commando.

To think some of us still have to do a Plug Chop to "try" and see what's going on...although I do have an O2 sniffer now...it's just cool as heck to see all of this data and actually know what's happening inside that thing.

Thanks for posting this.

Ta.

needing said:

comnoz said:

There is vacuum operated pump that circulates the fuel between the backbone tube and the fuel tank.
Originally I tried gravity feed but the fuel in the backbone got too hot from engine heat and the high pressure pump would vaporlock. Jim

Click to expand...

Hi Jim.
I much like the idea of utilising the spare space in the frame tube for fuel supply as I prefer the Roadster tank look but not the range limitation.
The video does not make it clear how the fuel tank and the frame tube are connected and how the fuel circulates between the two i.e. does the high pressure pump draw from the tube or the tank in your set-up? When refuelling, how does the tube level fill as the tank fills i.e. venting configuration? Could you provide a sketch / drawing of your tank and tube set-up please?
Ta.
Owen.

Click to expand...

The high pressure pump is submerged in the backbone tube. It is an in tank pump from a car.

Fuel from the petcock on the fuel tank goes to a vacuum operated [snowmobile] pump and is pumped into the backbone tube though a fitting near the rear of the backbone and a second fitting near the front of the backbone tube goes back into the fuel tank.

This circulates fuel through the backbone to keep it from getting too hot. The backbone tube will not fill by gravity from the fuel tank. Jim