texasscott1 wrote:
It's actually a sequential fire system because the injectors only fire when signaled for their individual cylinder. I forgot the number of degrees ATDC, I'll try to look it up again tomorrow. The reason they fire twice is because there's no cam position sensor.

Sounds like a good system to me because the squirt on the off stroke will help keep the intake valves cool and should be fully vaporized before the intake valve opens and the next squirt occurs.I know the spark plugs fire for every revolution one starts the combustion and 360 degrees later it fires again in the exhaust stroke. The other cylinder does the same thing. The lost spark is due to the lack of cam sensors. Do these injectors fire twice per revolution too?

ahamay wrote:
I know the spark plugs fire for every revolution one starts the combustion and 360 degrees later it fires again in the exhaust stroke. The other cylinder does the same thing. The lost spark is due to the lack of cam sensors. Do these injectors fire twice per revolution too?
I think you meant once per revolution and yes they do. On the off cycle the intake valve is closed so the fuel sprayed is vaporized against the hot intake valves so on the intake spray most of the total fuel the cylinder gets is already vaporized which, in my mind at least, makes for better combustion.

Also, unlike the 950 or 1300, the Road Star has an O2 sensor for each cylinder which should provide for better mixture control.

I have a question.

Lets just say the bike is running slightly lean, your plugs look ok, your happy, the bike seems happy.

Now you take your bike over a high mountain peak, you are nearing the top of this 7,000 foot peak, the bike is pulling.

What happens to the head temps?

Well i think this might be an answer of of why the Cobra FP is so good. Cycling 60 to 80 times per second and adjusting on the fly for the conditin you are in at the time.

River wrote:
I have a question.

Lets just say the bike is running slightly lean, your plugs look ok, your happy, the bike seems happy.

Now you take your bike over a high mountain peak, you are nearing the top of this 7,000 foot peak, the bike is pulling.

What happens to the head temps?


Um, they're probably going to go up since, well, you're climbing a ******* mountain... You don't think the stock ECU can note atmospheric changes and adjust accordingly?

River:
You're not going to look down one day and find that you've burned up your engine because you were running lean. It's a process that you should have been aware of far in advance of that. Running really lean typically provides some level of indication that it's occuring. Pinging, properly known as "detonation", is really hard to ignore, especially under load conditions like you're mentioning above.

Mod your bike, check your plugs once in a while, listen to your bike for signs of detonation. If the mods you do cause any issues that have to be remedied with a fuel processor, so be it. But, that's the time to consider it. If you can follow that simple logic, you should have a great running bike for a long time.

Does anybody disagree with that statement?


Rich

texasscott1 wrote:
It's actually a sequential fire system because the injectors only fire when signaled for their individual cylinder. I forgot the number of degrees ATDC, I'll try to look it up again tomorrow. The reason they fire twice is because there's no cam position sensor.

Sounds like a good system to me because the squirt on the off stroke will help keep the intake valves cool and should be fully vaporized before the intake valve opens and the next squirt occurs.
Correction: The injectors pulse BTDC. Now that I think about it probably at the same time the plugs fire. When the intake valve opens the full charge is waiting.

I do. Thanks for stating that. I thought this all started out with a question about a power commander. It looks as though its gone way beyond what the question was. From what I can see the carbbed guys will never buy an efi due to the scientific explanations of this topic.
Whatever happened to the KISS method. I got lost somehwere around btdc and atdc and so on.
I explained what my experience was it it wasnt great.
If you want a fuel processor the best bang for your buck is the Cobra. It almost sounds like I have shares in that system.
Just watch your plugs, the exhaust pipes will show different colors if u get too lean. Like u said listen to your bike it will tell you whats going on
The EFI R* is a great bike and here to stay. I have ridden from flat in southern Saskatchewan which is 817 m above sea level to the Beartooth Pass in MT and i didnt have a problem so that tells me my brain on my bike adjusted accordinly, NO problem with leaning out or working hard
The bikes brain will do what it has to do. Now my wifes Vstar on the other hand didnt want to barely run when we hit the top so right there is a drawback of carbbed bikes

Weeds166,

It started off with me being frustrated over all you hear about the lean problem and no real numbers.

Well, I got numbers tonight, I spent 227.00 intsalling an Inovate Powersports MTX-L A/F monitor - part number 3845.

I just finished getting the install done, it's dark and raining so I just got a reading at 20 miles an hour from the shop to the house.

Warming up its 13.5
Warmed up a little bit its 14-15

excellerating to 20 MPH it's 12-13.
At 20 MPH its 14-15

Its supposed to stop raining about mid morning tomorrow so I should be able to get some testing done.

I put a switch on the unit because you don't need it running all the time. I ran it direct to the battery and fused it.
Thats my story an I'm stickin toit.

I wish I could have back the hours I've wasted on this subject...

You've successfully convinced everyone that our fuel-injection is substantially more complicated than carburetor jetting...


Rich

Well let me ask this? Would running high octane vs the low octane help make the engine run cooler or is there not enough difference in the 3 grades of gas?