issues with running non premium gas
Road Warrior
Joined: Jul 2013
Posts: 1,649
Likes: 443
From: Indianapolis
Since all gas by regulation has 115,000 BTU's per gallon except winter gas which is 108,000 BTU's and BTU's are what provides the power the lower the octane the faster the burn. The faster the burn the more power is produced.
All mine run stronger than their stock counterparts because of the above.
All mine run stronger than their stock counterparts because of the above.
At about 12.5 to 13 air-fuel-ratio the mixture burns fastest.
A leaner mixture than that burns slower.
A richer mixture also burns slower.
" You might be surprised to learn that some of the highest octane fuels may also be some of the fastest burning fuels!"
Not all gasoline will have 108,000 BTU/gallon. Some areas use gasoline without ethanol. Even e10 gas can have between 5-10% alcohol.
You might be surprised by all the different types of gasoline that are required by regulation.
Here in Indiana we change the RVP 5 time per year.
Here is a sample of the different gasoline blends required in the US.
https://www.afpm.org/uploadedFiles/C...ine-Map(1).pdf
Last edited by shanneba; Sep 13, 2017 at 05:11 AM.
Road Warrior
Joined: Jul 2013
Posts: 1,649
Likes: 443
From: Indianapolis
For me it works just fine with E10 87 octane.
Knocking can occur before, during and after spark ignition but all come under the term spontaneous combustion which is a heat source other than the spark plug. Keep the engine cool and pinging can not happen.
The alcohol content acts as a refrigerant when it is atomized by the injectors as it is dramatically more volatile than gas. That causes a much cooler denser intake charge.
1.The auto ignition temperature of 90% gas and 10% ethanol will be about 30 F higher than straight gasoline.
Straight gasoline has an auto ignition temp of 495 F.
Ethanol has an auto ignition temp of 793 F.
Mixing 90% gas and 10% ethanol raises the auto ignition temp to about 525 F
2. The latent heat of vaporization of the mixed fuel will increase, that will reduce the intake charge temp slightly.
gasoline has LHV of 10 BTU / Lb of air at stoichmetric mixture at 60 F.
ethanol has LHV of 44 BTU / Lb of air at stoichmetric mixture at 60 F.
Mixing them at a 90/10 ratio raises the LHV to 13.4 BTU / Lb of air at stoichmetric mixture at 60 F.
Road Warrior
Joined: Jul 2013
Posts: 1,649
Likes: 443
From: Indianapolis
Let me know if you get any data. It looks like the 2014 + Sportsters may have a ECM connection to the Coil, ION Sense. Maybe you do have "knock Control"
Banned
Joined: Dec 2016
Posts: 250
Likes: 89
From: lower 48
I don't see anything to turn it on/off. it could be an always on feature.
I attached the text explanation regarding "adaptive knock retard" in the knock section
Looks like '14 and up have some knock control capability.
Road Warrior
Joined: Jul 2013
Posts: 1,649
Likes: 443
From: Indianapolis
That same info shows up in WinPV on the 2013 tunes.
What are the other "Knock Control" Settings you see in your stock tune?
In my 2013 tune the temp is set to 462F (I have never seen a temp this high)
The Map is set to 60 kPa.
The ignition coil part number is the same between 2013 and 2014 Sportster models.
The Updated ECU and Software level, 374 I believe, plus the additional connection to the ECU may enable the knock control.
What are the other "Knock Control" Settings you see in your stock tune?
In my 2013 tune the temp is set to 462F (I have never seen a temp this high)
The Map is set to 60 kPa.
The ignition coil part number is the same between 2013 and 2014 Sportster models.
The Updated ECU and Software level, 374 I believe, plus the additional connection to the ECU may enable the knock control.
Banned
Joined: Dec 2016
Posts: 250
Likes: 89
From: lower 48
knock control minimum map = 54.9
knock control minimum map hysteresis = 52
knock control min rpm = 800
knock control min temp = 239C or 462F
knock control min temp hysteresis = 239C or 462F
knock event spark retard adder = 1 degree
knock spark retard removal % = 14.8%
knock retard removal rate = 0.496 seconds
max knock retard = 6 degrees
knock control minimum map hysteresis = 52
knock control min rpm = 800
knock control min temp = 239C or 462F
knock control min temp hysteresis = 239C or 462F
knock event spark retard adder = 1 degree
knock spark retard removal % = 14.8%
knock retard removal rate = 0.496 seconds
max knock retard = 6 degrees
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Road Warrior
Joined: Jul 2013
Posts: 1,649
Likes: 443
From: Indianapolis
I have seen tunes from Dynojet for touring models where there is an on/off 1/0 switch / setting to turn off the knock sensing, I was just wondering if the Sportster had the same thing.
I also noticed the 2014+ Sportsters have a couple of settings to change the ignition timing at idle too. It looks like it adds/deletes timing if the idle rpm is +/- 100 rpms from set speed.
I also noticed the 2014+ Sportsters have a couple of settings to change the ignition timing at idle too. It looks like it adds/deletes timing if the idle rpm is +/- 100 rpms from set speed.
