My take reading this is that no one is saying any such thing. I had a dealer map on my TC and a subsequent dyno tune showed it lean still in certain rpm ranges and too rich in others. A dyno tune isn't about getting a fraction of a second down the quarter nor about numbers, it's getting your motor tuned optimally so it will go the distance. A slightly off tune won't necessarily manifest itself in obvious ways such as deceleration pop but just because you think it's riding great doesn't mean it actually is.

Back to Tuner pros and cons - well, it depends on which Tuner. The EPA versions don't allow full calibration (con), but keep your warranty (pro). Race tuners of any make allow for full parameter tuning (pro) but may void your warranty (con).

My advice is if you do any Stage work get it tuned eventually with a race Tuner so it's spot on today and for the rest of that build life.

 

I dunno. I'd say that there are literally millions of bikes that have after market parts and have "gone the distance" with never seeing a dynometer. Besides, since this is a touring forum (for now) that tight M8 tune will go out of spec as soon as humidity/elevation changes or parts wear come into play. I mean sure, if you want tight dial-in and your shop-operator-dynometer is up to snuff, knock yourself out. But let's not make more of it than it is. The tolerances that these parts are built to and that fact that the stock maps are based on dyno tunes of these parts means you're going to be darn close and the ECM can account for the rest. If anyone really wants to be tight all the time then they should put some wide-band oxygen sensors in and an auto-tuner. That way the bike can self adjust for optimal AFR.
Actually, I would say that is the only metric that matters a whit. IMHO, of course.

Not much to add to the pros and cons, they seem spot on to me.

 

Depends what you mean by distance. Lots of folks get a new bike every so often. Me, well I plan on this bike lasting me out my riding days, so why not have it tuned to this motor's exact specs rather than the bike HD had with SE parts fitted?

Every engine is different slightly. Every engine will benefit from being tuned, and the HD canned maps are made for using SE components. If you use non SE components, the further away your bike is from being tuned to the best it can be.

Whilst these bikes will make adjustments for elevation etc if they start from a spot on base line then variability can always be accounted for.

That's how I see it, up to each owner if near enough is good enough.

 

I can say with great certainty what you say is the truth, the whole truth, and nutin' but the truth.
However, one thing you missed as a variable is injector output.
These production injectors are +/- 10+% so since tunes are either done by mfgs using calibrated injectors or a tuner/shop using a specific bike and whatever injector outputs it has, this accounts for why rarely, canned, borrowed or custom tunes don't work the same with other bikes even with the same exact parts.
This coupled with all the cam and exhaust companies making hop-up parts with little or no tolerance oversite other than their own in-henhouse adds to the variety and need to recalibrate/tune.
Bob

 

What tuners are the good ones
I see a few recommendations for the Harley Tuner because it will let me keep my warranty, I would assume the Harley tuner would have enough adjustment for a set of Samson Pipes? With its I could swap back pipes if I had a problem with the eng.
the other 3 i have my eye on are
1) Vance and Hines Fuel Pack 3
2) Dynojet Power Vision
3)Zippers

I should probably get a few thousand miles on the eng before i do this to insure the Eng is not gonna develop a oil pressure problem or something before I get pipes or a tune.

I had a stage one with Vance and Hines Bigshot Duals and it only had a dealership flash and ran great but that was back in 2006
PHX

 

I agree. It's not just the injectors that have a tolerance. Everything does. That is where the dyno comes in. I have yet to have a bike tuned that didn't show an improvement. Fro $250 bucks it's well worth it to me and that is all that matters. Get a canned map if you want. I am running one on the M8 now strictly for the warranty but when it's up it's going in.

 

The ECM does have the ability to adjust, as long as the map in the ECM has been calibrated for the components involved. Since they know the tolerances of stock components, HD has a range, built in to the map, that's designed to account for possible head flow differences, injector differences, altitude, etc ( because they don't want customer complaints), and as long as all things are stock, it should be OK- not great, not perfect, just OK. OK is what most people describe as "fine". Decent manners, decent mileage, no real complaints, as long as you're running the fresh 91 octane called for in the owners manual. Fine.
Think of the factory base map as a base line-call it "center"-it can adjust for a few percent one way or the other, say, +/- 15%. All stock components, you have enough range to account for injectors at the low end of spec, combined with heads at the high end of spec, and a less then stellar fuel, at elevation- Not gonna run its best, certainly not great, but "fine". OK.
Now you start changing components without calibrating the ECM- new air cleaner- shift X% away from center, add pipes, call that Y% shift from center, so now the range is offset XY%. No more room for altitude adjustments, fuel quality variances, tolerances, etc. Bike runs less than "fine", because the ECM has no adjustment available.
Throw in a base map from some online guru, and if that map was done with the same parts that you have installed, it may be close to "fine". May still run less than "fine", but be closer to center.
Get it re calibrated to reset the ECM to the components installed, and now the map in the ECM is truly at center-the injector variations, and head variations, etc all accounted for. The improved airflow from the air cleaner and pipes accounted for. Now the ECM has the full intended range of adjustment available for variations in fuel/altitude/etc.

 

The junk HD Tuner will be fine for Samson Slipons. But if your looking at a open head pipe / no cat. No

 

Yes I want a full system no cats, ceramic coating and some bark. As far as HD is concerned all I need is the Bike they can keep all the other Junk
PHX

 

OK,,, open head pipe warranty gone. So get what ever tuner you want. Simple