How not to spend $$ on a dyno.

[RainDodger]

Yes, I know that to properly tune, you should use a dyno. However....

Here's my experience: When I bought my Ultra in 2005, I had the 95" kit put on before I even picked it up. My next mod was to put in cams about 2 years ago. My NEXT mod will be to the heads, but that won't be until I need to do top end work. When I put the cams in, I looked at the specs of my chosen cam and compared them to the HD Stage II mods and came to the conclusion that before putting in a fuel controller, I would at least TRY the HD stage II download and see how the bike runs. It turns out that the bike ran great, with no snapping or popping, and decent performance.

Well. At the time I put the cams in, I bought a Cobra FI2000R just in case the stage II download didn't work very well. It has been sitting on my bench for 2 years.

A couple of weeks ago I was putting on new plug wires and had my gas tank off. I figured what the heck, and installed the Cobra fuel controller to see what it felt like. Major change. The bike is smoother, starts better, has better throttle response and I think it's running a little cooler as well because it's running a little richer mixture and delivering fuel over a little longer interval.

The first mileage check showed 41 around town/commuting, and 43 on the highway. Since then, I've s-l-o-w-l-y been leaning the mixture in the low and mid-range bands. The bike is still starting better and running far better than with the HD stage II download and my mileage is creeping up further. I'll continue to adjust until the performance is impacted, then richen it a tad and call it good.

This is simply a note to remind you guys that sometimes you can improve things from stock without spending big $$ on more expensive controllers, dynos, and having other guys tune your bike. It may be a slight compromise, but for the average guy on a bagger, this might be a great way to go. If the stock download is "working fine", you might find that a simple fuel controller makes it even better.

Roger

[FLTRI]

Roger,
Let's take a look at what you've stated here:

.....It turns out that the bike ran great, with no snapping or popping, and decent performance.
......It (the Cobra enrichener) has been sitting on my bench for 2 years.

Sounds like you were happy/satisfied with the way it ran for 2 years.

....installed the Cobra fuel controller to see what it felt like. Major change. The bike is smoother, starts better, has better throttle response and I think it's running a little cooler as well because it's running a little richer mixture and delivering fuel over a little longer interval.

.....and running far better than with the HD stage II download and my mileage is creeping up further. I'll continue to adjust until the performance is impacted, then richen it a tad and call it good.

Since the Delphi EFI is precisely mapped for virtually every TP/RPM and the enrichener you are using adjusts large areas (swaths) of TP/RPMs with a screwdriver would you agree that maybe there are specific TP/RPM places in the mapping where you need more OR less fuel than what you controller can adjust? ie: Say you need more fuel @ 20%tp/2250rpm but need less @ 20%tp/2500rpm, etc. what can you do? This happens all the time and the "swath" fuel controllers simply can't make specific TP/RPM changes.

So, what I get from your findings is the Stage 2 download was "the bike ran great".
Then you added the fuel enrichener and found "Major change. The bike is smoother, starts better, has better throttle response and I think it's running a little cooler"

Now the question: If you felt marked SOP improvement adding a fuel enrichener, isn't it conceivable that by precisely tuning all the TP/RPM points in the mapping the bike could feel even better than it does right now? In other words what you had originally thought ran great, after adding the enrichener it ran much better, however you didn't realize this until after you actually experienced it.

So it is reasonable to say: what a rider currently feels is the best he knows.....until he experiences better.
IMO There is simply no comparison to precise, individual cylinder, TP/RPM tuning. So, believe it or not, there's even more left (smoother, better throttle response, and overall power) from your build by precisely measuring and tuning you EFI system.
As always, JMHO,
Bob

[RainDodger]

You are exactly, precisely right. I totally realize that to do a "perfect" job of tuning, one should use something more precise than the Cobra I'm using, or any DFO that simply adds fuel. Ideally the ranges should be divied (sp?) up into the smallest areas possible, and individually mapped. You're also right that a dyno is also the best choice. All I'm saying is, after installing the Cobra, it does indeed feel better (seat-of-the-pants-wise) than with the stock HD stage II download. Obviously, better performance could be had with a more precise metering device aided by a dyno.

Nevertheless, it feels better now than it did, and it wasn't bad before. I'm not saying it couldn't be better.. but I AM saying it's pretty #$%^ adequate. For a whole lot less than the $$ spent on a dyno. Fwiw.

Remember: an opinion is worth precisely what you pay for it, and nobody paid me for this one!

Roger