[Wobblypop]

I have been running 87 octane in my '07 Kingpin. It seems to run fine and gets very good fuel economy. (50 miles per US gallon) I have felt that the odd time I am on the throttle hard wanting maximum performance is not often enough to warrant the extra cost of fuel. I have been relying on the knock sensor to pick up any sign of detonation and retard the timing a little if need be. Recently I have started wondering if this is good logic. Does my '07 Kingpin utilize knock sensors?

 

[iabob]

No. The only knock sensor on your Victory is you. Running the lowest Octane without knock will net you the best performance, mileage, and cleanest combustion chamber. If you're not confident of your ability to recognize knock just run premium. On my 07 Kingpin, which is running higher compression pistons, it runs great on 87 in cooler months. Right now I'm running 91.

 

[Wobblypop]

I haven't noticed any pinging but my guess is that a knock sensor would pick up more than my ear. On the other hand I would think my ear would pick up detonation that is severe enough to start damaging pistons. My bike is completely unmodified with the factory 9.8:1 pistons. I normally ride at about 3000 -4000 feet of elevation. I ride in temperatures between 70 and 85 degrees. Very rare that I see over 85.

 

[vision_nut]

Never run 87 if your going up hills or in high elevation.
50 mpg is way to lean your burning up your valves. Mid 40's is best

 

[Half_Crazy]

The only knock sensor on your Victory is you.

True that.

 

[waterhog]

Never run 87 if your going up hills or in high elevation.
50 mpg is way to lean your burning up your valves. Mid 40's is best

Agreed except high elevation. Because O2 density decreases, lower octane fuel is less likely to contribute to detonation compared to low elevation. Since Victory's ECU uses MAP relative to outside barometric pressure when making fuel adjustments, altitude should not have a significant effect on detonation unless extreme.

 

[nickr914]

I haven't noticed any pinging but my guess is that a knock sensor would pick up more than my ear. On the other hand I would think my ear would pick up detonation that is severe enough to start damaging pistons. My bike is completely unmodified with the factory 9.8:1 pistons. I normally ride at about 3000 -4000 feet of elevation. I ride in temperatures between 70 and 85 degrees. Very rare that I see over 85.

It sounds like a marble slamming your intake....

 

[bikendad]

There are NO KNOCK SENSORS ON VICTORY ENGINES. If you're getting knock go to 89 octane.

 

[poptop]

I always find this topic so interesting,I know people rideing completly stock Vics that would trialer there dame bike before running anything but 91 or at least 89!
On the otherhand I use the lower octane85 but almost always 87 octane,the bike runs and rides like a trooper withit!
So I never question it.
I wish more folks understod this simple principal !
In all honesty I must admit that when in the rockies mountains next door to me and very warm temps 90 and above ,I do use a higher octain fuel! Never here the marbles in the intake as it has been discribed!

 

[Wobblypop]

I can understand using high octane fuel above 90 degrees but if there is ever a case for using low octane fuel it would be at high elevation .... so riding in the Rockies.

 

[Tenax66]

I'm next door to the Rockies and at this point all my riding is at 3000 plus. I have ran both 89 and 91 without issue but since my tuning session and some advances to timing thought I better run 91 always. I've never had a knock, ran the bike from 9 degrees celcius to 33 degrees celcius on my recent big road trip. I ran both 89 and 91 and kept octane boost in my bag in case I needed. Don't think I would be comfortable running regular gas (87) but I think 89 is going to be my go to. It sounds like its better for the engine, better power. And on a hot day (which is rare around here) i'll have my octane booster still in the bag. Our gas is so expensive in Canada right now, that pricing it out its actually cheaper to add booster than to use premium gas!

 

[nickr914]

Well didn't wanna turn this into a me thing...
yesterday my bike was being a crybitch
I don't if it's because it had to watch me ride off with the vision while it sat there, for a couple days(week I put over 1k on it in a week) but...

The ***** made my clutch lever tighten up, I'd clutch, shift, release, was fine... Till full throttle, then it went (WRAR WAAARRRRR), but barely moved.. clutch level released 3/4, stopped at a gas station took apart lever,
cleaned, fine...

Then after a fill of 91 rec fuel(non ethanol) was pinking like a mother, never had that happen before, I rode by my friend, hit 4500 and click, click, clickity click, click.... Shifted, hit the throttle again, clickity, click, I let off... My friend tells me when we stopped, "you went by me, got to the bottom of that hill, big puff of black smoke came out of both pipes and your bike lifted...."

But yeah, I would typically get 1 - 2 marbles going WOT(click, click, WAAAAAAARRRRRRR, my bike screams war when it's goin ...)

I only run 91 non ethanol, the fill up before that I was at 45mpg, I'm guessing I got some bad gas...

 

[Wobblypop]

Something to keep in mind when choosing octane of gas is the compression ratio of your bike. I believe 2007 and prior are higher compression engines than 08 and beyond.

 

[waterhog]

One benefit of using a flash device such as PVCX or Maximus is that you can easily switch from one tune to another as environmental conditions change. On PVCX it takes about 5 minutes.

I tuned my bike in April/May where temps were mostly in the 60s and 70s, with a couple of days in the 80s when I rode. I even did a dyno test run to get objective numbers and double-check for pinging. The same tune, when temps hit high 80s and I was stuck in stop-and-go traffic would start pinging when accelerating in the mid-2000-to-low-3000 rpm range. So I created a more conservative tune (reduced spark timing and further enrichment) which I've been riding in June/July with no pinging. In September/October I'll switch back to the April/May tune.

 

[ughammer]

In Germany we have only Super 95 Octan with 5 or 10% Ethanol , Super plus with 98 and premium with 102 Octan and I see no difference.
I had a US mapping and it was set to fat .
If I ride slowly (75 mph ) I need 39 mpg if I ride over >100 i need 27 mpg
It doesn't matter what fuel I drive.
The mapping was tuned for E10 gasoline

 

[nickr914]

One benefit of using a flash device such as PVCX or Maximus is that you can easily switch from one tune to another as environmental conditions change. On PVCX it takes about 5 minutes.

I tuned my bike in April/May where temps were mostly in the 60s and 70s, with a couple of days in the 80s when I rode. I even did a dyno test run to get objective numbers and double-check for pinging. The same tune, when temps hit high 80s and I was stuck in stop-and-go traffic would start pinging when accelerating in the mid-2000-to-low-3000 rpm range. So I created a more conservative tune (reduced spark timing and further enrichment) which I've been riding in June/July with no pinging. In September/October I'll switch back to the April/May tune.

I have other cable or laptop

 

[waterhog]

In Germany we have only Super 95 Octan with 5 or 10% Ethanol , Super plus with 98 and premium with 102 Octan and I see no difference.
I had a US mapping and it was set to fat .
If I ride slowly (75 mph ) I need 39 mpg if I ride over >100 i need 27 mpg
It doesn't matter what fuel I drive.
The mapping was tuned for E10 gasoline

Theoretically higher octane gas leads to more efficient combustion hence better fuel economy. In practice, the quantitative benefit may be too marginal to notice. Considering its higher cost, per dollar (or euro) spent it's a losing proposition unless there is another compelling reason. In my case, I use 91 or 93 octane gas (highest available at pumps) solely to mitigate detonation. Much of Indiana is not much above sea level.

 

[waterhog]

I have other cable or laptop

You don't need a laptop to flash the ECU with PVCX. I have 3 tunes on the flash device: summer, spring/fall/winter, and stock. Pull over, turn off the engine, flash and it's done. About 5 minutes.

 

[nickr914]

You don't need a laptop to flash the ECU with PVCX. I have 3 tunes on the flash device: summer, spring/fall/winter, and stock. Pull over, turn off the engine, flash and it's done. About 5 minutes.

I have otg cable for phone, or I can store two tunes on the PC V, and flip a switch...

 

[waterhog]

I have otg cable for phone, or I can store two tunes on the PC V, and flip a switch...

Sounds like a good solution. No need to replace existing PCV with a flashing device on performance grounds alone.