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Discussion Starter #1
I found a pretty good deal on the power commander III the other day for my Vulcan 1600 so I went ahead and ordered it. I eventually want to do the Vance and Hines exhaust and the Thunder MFG air intake, so I will need it anyway.

I was curious if anybody had any first hand experience with the power commander allowing them to run 87 without pinging? With only 9:1 compression I have read that the only reason Kawasaki required 90 octane on these is because they tuned them so lean for emissions. I have downloaded the software and verified that the PC map for a completely stock bike does add fuel in the mid range, although it actually takes away a significant amount at WOT. My guess is they went lean in the midrange for emissions and then rich up top for safety.

Before anybody says it, no I did not order the PC just so I thought I could run regular fuel, that would be pretty foolish. If it eliminates pinging by adding fuel, the fuel may be cheaper but I'll be burning more of it so worst case it would be a wash. At the same time if it does allow me to run a lower octane, why would I not?
 

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if it takes away fuel at WOT, that would make it run lean, yeah?

*I have no experience to actually give, but I'm happy to share my opinion*

In theory, I think you would be fine running a lower octane with a power commander. Since, like you said, the engine is running a pretty low compression ratio, it may be alright. But like you said, if you're dumping more fuel to compensate, you may end up making less power, and have to burn more fuel to compensate, negating any money you may save from running a lower octane.

I'm in the process of doing a similar build to your goals. I currently have the Vance and Hines big shots installed, and will be putting a PC next. Then thunder MFG big air kit.

I'm interested to find out what you discover!
 

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Discussion Starter #3 (Edited)
if it takes away fuel at WOT, that would make it run lean, yeah?

*I have no experience to actually give, but I'm happy to share my opinion*
Not necessarily. I've tuned more cars than I can count and it is not terribly uncommon to have them running rich at wide open throttle. Generally emissions testing is concentrated on where the engine is operated the most, part throttle cruising. Since the engine is generally not under a super heavy load in this range they tune them as lean as possible to minimize emissions. At wide open throttle and heavy load situations things can go south in a hurry. A richer burn here will be cooler and will help prevent detonation and is thus "safe." It is fairly well standard practice to tune them a little bit richer than optimal for the purposes of just covering their butts and keeping it safe. So yes taking away fuel will make it leaner, but not necessarily make it TOO lean.

In theory, I think you would be fine running a lower octane with a power commander. Since, like you said, the engine is running a pretty low compression ratio, it may be alright. But like you said, if you're dumping more fuel to compensate, you may end up making less power, and have to burn more fuel to compensate, negating any money you may save from running a lower octane.
This is where there is so much mis-understanding in the world it is not even funny. Some people swear up and down that high octane fuel gives you more power. Although it is true that many performance engines require a higher octane fuel, they do not make the power because of it. The octane rating of a fuel determines how hard it is to detonate. If everything else is equal, a higher octane fuel will burn slightly cooler and make LESS power than a lower octane fuel. So why high octane? High performance engines tend to have higher compression and thus are prone to detonation. Increasing the octane rating to prevent detonation will compensate and usually the increase in power from the compression bump offsets the less volatile fuel. Thus to make the most power, you want to run the LOWEST octane fuel possible for your application.

So what does this mean for us? They tuned it super lean for emissions. At only 9:1 compression there is no way it requires high octane fuel unless it is super lean. So what do we get:

1. We add more fuel at a given throttle position and RPM to cool it down a little bit. This would increase fuel consumption.
2. Because the combustion is now cooler we can run a lower octane fuel, which will explode more violently and provide more power.
3. Because the throttle position X at RPM Y now provides more power than it was, we might be able to run at throttle position X-Z to obtain the same desired power. Less throttle means less fuel, which would decrease fuel consumption.

So the question becomes do the factors that decrease fuel consumption outweigh the factors that increase it? Maybe, maybe not. If they do not, does the money saved on non premium fuel offset the economy difference? Maybe, maybe not.

Fortunately I keep meticulous fuel economy records. I can tell you the MPG on every tank of gas I have ever bought. Armed with this information I should be able to quantify any gains or losses in economy from the power commander.

I'm in the process of doing a similar build to your goals. I currently have the Vance and Hines big shots installed, and will be putting a PC next. Then thunder MFG big air kit.

I'm interested to find out what you discover!
Since you are interested, I will most certainly keep you updated! Because I do not have the money to do it all at once, I will be able to track and compare the following:

Stock Fuel
Power Commander Only
Power Commander and Exhaust
Power Commander and Exhaust and Intake

That is the order I plan on doing the upgrades because Dynojet has those maps available so at no time should I be running around with something grossly out of tune. Once I get it all done and ride around for a while I will probably take it to a shop and have them dyno tune it to see if they can massage a few extra horses out of it. No two vehicles behave exactly the same, even with the same mods.
 

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Discussion Starter #4
I received my power commander today. Installation was so simple a total idiot could do it. Now I just need some decent weather and some time to see what results I can come up with.
 

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This is why the Caddman mod of soldering the resistor in-line with the FI circuit is genius. For pennies you get most all the benefits of the FI Controllers. It gives the factory tuned lean-burning 1600s more fuel across the board. Surprisingly, my fuel consumption is only slightly less efficient. A pull of the spark plugs after about 2K miles showed improvement across all cylinders.
 

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Discussion Starter #6
I've logged countless dyno hours on countless machines and I can tell you although the "cheap fixes" like that may address one issue, they very often cause others. Now for a bike that essentially runs in open loop mode anyway the results may be acceptable, but in my book they are no substitute for actually tuning. This is my opinion based on my experience tuning. To me it was worth the money to buy the power commander, maybe it isn't for you.

As far as my PC results so far, I was busy all weekend and did not get to ride, today was my first real ride. I did not notice any OMG "you've gotta have this" type of difference, but it sure is running good. I have certainly not created any negatives. I did fill up with 87 today and noticed no pinging. Since I previously had 93 in the tank my math puts the current octane level at about 88.3. Only time will tell on the fuel economy.
 

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I've logged countless dyno hours on countless machines and I can tell you although the "cheap fixes" like that may address one issue, they very often cause others. Now for a bike that essentially runs in open loop mode anyway the results may be acceptable, but in my book they are no substitute for actually tuning. This is my opinion based on my experience tuning. To me it was worth the money to buy the power commander, maybe it isn't for you.

As far as my PC results so far, I was busy all weekend and did not get to ride, today was my first real ride. I did not notice any OMG "you've gotta have this" type of difference, but it sure is running good. I have certainly not created any negatives. I did fill up with 87 today and noticed no pinging. Since I previously had 93 in the tank my math puts the current octane level at about 88.3. Only time will tell on the fuel economy.
Ahemsa, you're likely correct in your overall assessment. We've got quite a few Meanie owners who've run the resistor mod for well over 5 years with no problems. Full tuning offers benefits you can't acheive otherwise though. For someone on a budget though, the resistor does what it does simply and effectively.
 

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Discussion Starter #8
Sure. Every person has to do their own cost / benefit analysis. I looked at all the options and found that the PC is the best fit for me.

A friend of mine has an FZ-09 and he is seriously looking at the software to allow him to tune the factory ECU. Of course they make a power commander for it but all it does it sit on top of the factory ECU. Tuning the factory unit allows changes to more features and the cost is very comprable. Why would you NOT go with the more flexible route if the price is similar? Ultimately he has a lot more options than we do. Sadly there aren't just tons of options for 10+ year old cruisers.
 

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Discussion Starter #9
The average economy for the 31 tanks of gas before the power commander was 35.2mpg. I have since run 2 tanks with the power commander for an average of 34.9mpg. Lower, yes, but hardly enough data to be definitive as of yet. What is definitive is that it didn't cause the mileage to completely tank. I can also say that it's purring along perfectly happily on 87 octane. Longer term results will follow as I have them.
 

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Discussion Starter #10
Just a quick update on this subject. I ordered a new exhaust system and installed it so the time of my pure stone stock to pure PC only comparisons has ended. I knew the exhaust was coming and I had yet to take a decently long trip to try out the sustained cruising mileage, so I did that last weekend. By sustained cruising I mean relatively open roads, twisties, but no stop and go. Not really highway though because I kept the speed under an indicated 70MPH.

This weekend I achieved 47.66mpg, which is a little less than my best of 48.30mpg. I have a hard time calling this statistically significant because that is only comparing two data points that were taken months apart and on different highways, weather conditions, tires, etc. If you want to go with that number though, we'll say I may have lost 0.64mpg. Looking at averages over all riding, for the 4189 miles I rode with the bike completely stock I averaged 35.2mpg. For the 1758 miles that I rode with just the power commander I averaged 35.0mpg. Again not exactly comparing apples to apples because the riding conditions weren't identical so I have a hard time considering this difference significant, but we'll go with it anyway and say 0.2mpg.

What I can say with absolute certainty is that with the power commander, the bike doesn't complain in the slightest about burning regular old 87 octane as opposed to the 90 it supposedly needs. Armed with that knowledge we can run some numbers.

Today the cheapest 87 octane in town is $1.96. Our midgrade is 89 so that doesn't hit the 90 requirement. Cheapest premium in town is $2.57. We'll use the highway numbers for comparison because they represent the biggest difference loss in economy.

For a trip of 1000 miles:
Stock I could average 48.30mpg, which means 20.7 gallons, which means $53.21
With power commander I could average 47.66mpg, which means 20.98 gallons, which means $41.12

That's a total of a $12.09 savings per 1000 miles by going with the power commander and using regular fuel instead of premium. A quick Google search tells me that a power commander III for this model bike can be had for $350.96. This means that if you cruise on the highway the power commander will pay for itself in 29k miles.

Worth it? I guess you've gotta make that determination for yourself. I know for me it was worth it because when I found a killer deal on an exhaust I was able to just jump on it without having to worry about the woes of re-tuning, and I'll be able to do the same for an air intake.
 

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Discussion Starter #11
On a related note, to revisit the idea of the resistor mod to provide more fuel across the board. Attached is the VN1600 stone stock map from DynoJet. We can only assume these numbers are based on dyno tuning a stone stock bike.

If you look right in the middle of the graph at you see them adding fuel, which seems to re-enforce what everybody knows, that these bikes run lean from the factory. If you look at other spots on the map though you can see that they actually take away fuel over large areas. In fact, if you run the average of the entire table, the average is to take away 1.3% fuel. That's funny, I thought they ran lean? They do, but not everywhere, and that is the problem with making global changes.

Wanna fix the lean running at cruise, well you just made everywhere it is too rich even worse. Want to lean out where it is too rich, then you just made the lean places even worse. Thus I will stand by my original statement that the resistor mod is no substitute for actual tuning, at best it is a band-aid. Ultimately the decision comes to the owner as to if they are satisfied with a band-aid, or if they want to go to the hospital, and the costs are pretty much in line with that analogy.
 

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