Proof you don't need a tuner
Road Master
Joined: Dec 2012
Posts: 848
Likes: 30
From: CO
As for my bike.............2011 FXDC.......Vance and Hines slipons (cats were in the mufflers, so they're gone)........SE airbox..........download..............my bike runs great.............cooler..........no pops, backfires, etc. .............crisp and clean. So?????
Club Member
Joined: Jul 2014
Posts: 11,469
Likes: 3,572
From: Idaho
Still waiting for an answer to this question:
For those of you who claim that your engine life will be shortened, or damage done, where are your stats for that? I've seen none, just the opposite in fact.
As for my bike.............2011 FXDC.......Vance and Hines slipons (cats were in the mufflers, so they're gone)........SE airbox..........download..............my bike runs great.............cooler..........no pops, backfires, etc. .............crisp and clean. So, am I hurting my engine?????
For those of you who claim that your engine life will be shortened, or damage done, where are your stats for that? I've seen none, just the opposite in fact.
As for my bike.............2011 FXDC.......Vance and Hines slipons (cats were in the mufflers, so they're gone)........SE airbox..........download..............my bike runs great.............cooler..........no pops, backfires, etc. .............crisp and clean. So, am I hurting my engine?????
So his actual question is: "Yeah, so everybody says you don't need to do a tune, but I did a tune and my bike isn't damaged! So what's up with that?!?!"
Good grief.
Grand HDF Member
Joined: Jun 2008
Posts: 3,983
Likes: 2,144
From: Ohio
The point is this. Countless posts on countless forums claim the dealer download "does nothing, is worthless, a waste of money, adds no fuel, bike is still lean, etc." I've even seen one person who claims the dealer download will take years.....yes, he said years....off the life of your engine. So, I just want to know if any of that is true, or not. I don't know why that apparently upset some of you though.
I posted before that I know of two bikes with lots of miles, and no problems. Some of you say the download does nothing, some of you are saying it IS a tune. So which is it?
I posted before that I know of two bikes with lots of miles, and no problems. Some of you say the download does nothing, some of you are saying it IS a tune. So which is it?
Last edited by hd4evr2008; Feb 12, 2015 at 11:47 AM.
It sounds like some people don't realize a dealer-download is a re-tune.
So, I assume they don't realize that they spent half the cost of a tuner to buy a single tune.
Even then, the downloaded tune is a general version for one's general setup, not a specific tune for a specific bike.
So, I assume they don't realize that they spent half the cost of a tuner to buy a single tune.
Even then, the downloaded tune is a general version for one's general setup, not a specific tune for a specific bike.
Club Member
Joined: Jul 2014
Posts: 11,469
Likes: 3,572
From: Idaho
The point is this. Countless posts on countless forums claim the dealer download "does nothing, is worthless, a waste of money, adds no fuel, bike is still lean, etc." I've even seen one person who claims the dealer download will take years.....yes, he said years....off the life of your engine. So, I just want to know if any of that is true, or not. I don't know why that apparently upset some of you though.
I posted before that I know of two bikes with lots of miles, and no problems...
I posted before that I know of two bikes with lots of miles, and no problems...
That's why most of us here have been saying that you CANNOT make blanket statements like "never" or "always", because everybody's situation is different.
The ECM (Engine Control Module) in your bike came from the factory with specific settings. Downloading different ECM settings retunes the engine. Period. Just because the changes weren't determined using a Dyno doesn't mean changes weren't made.
Grand HDF Member
Joined: Jun 2008
Posts: 3,983
Likes: 2,144
From: Ohio
Lots of people say lots of things on the internet.
That's why most of us here have been saying that you CANNOT make blanket statements like "never" or "always", because everybody's situation is different.
Lots of people say lots of things on the internet.
The ECM (Engine Control Module) in your bike came from the factory with specific settings. Downloading different ECM settings retunes the engine. Period. Just because the changes weren't determined using a Dyno doesn't mean changes weren't made.
That's why most of us here have been saying that you CANNOT make blanket statements like "never" or "always", because everybody's situation is different.
Lots of people say lots of things on the internet.
The ECM (Engine Control Module) in your bike came from the factory with specific settings. Downloading different ECM settings retunes the engine. Period. Just because the changes weren't determined using a Dyno doesn't mean changes weren't made.
Road Master
Joined: Aug 2012
Posts: 854
Likes: 20
From: CT
Nice try, but the engine doesn't actually spend much time at 14.7.
14.7 is fine for idle or super-easy puttin', which is about the only time the engine runs at that mixture. Once the throttle opening and rpms increase, the bias table values cause the mixture to richen (while still in closed loop), and it's no longer at 14.7.
As throttle opening and rpms increase further, the system goes into open loop, and the mixture gets richer yet. So 14.7 doesn't have much to do with the actual fuel/air mixture used during most riding.
Sure, richening beyond factory-ish values will cool the engine a bit, but I don't ever ride in "Daisy Dukes"
(or any kind of shorts), so a little more engine and exhaust heat doesn't bother me.
14.7 is fine for idle or super-easy puttin', which is about the only time the engine runs at that mixture. Once the throttle opening and rpms increase, the bias table values cause the mixture to richen (while still in closed loop), and it's no longer at 14.7.
As throttle opening and rpms increase further, the system goes into open loop, and the mixture gets richer yet. So 14.7 doesn't have much to do with the actual fuel/air mixture used during most riding.
Sure, richening beyond factory-ish values will cool the engine a bit, but I don't ever ride in "Daisy Dukes"
(or any kind of shorts), so a little more engine and exhaust heat doesn't bother me.
Club Member
Joined: Jul 2014
Posts: 11,469
Likes: 3,572
From: Idaho
Oh, no. It's worth it. In my opinion. 
I haven't decided how much money I want to put into mine, because I still have this Road King fantasy spinning around in my head.
But, in the meantime I wanted my bike to run as well as it could, particularly given the fact that it gets pretty hot here in the summer. And, if I do decide to start doing things, I'll need the tuner module anyway. So, I bought a SEPST and had a tech who knows what he's doing do a smart tune for me. Two hours labor. Can't beat that.
Keep in mind, the bike is bone stock. I had a before and after dyno run done, just to see what happened. AFR dropped to the mid-13's, and from about 1,500-3,500 rpm I picked up between 4-5 ft-lbs of torque and 2 hp. Decel popping is gone. Throttle response is enormously better!
Bone stock, just a quick tune. I'm a happy camper.
I haven't decided how much money I want to put into mine, because I still have this Road King fantasy spinning around in my head.
But, in the meantime I wanted my bike to run as well as it could, particularly given the fact that it gets pretty hot here in the summer. And, if I do decide to start doing things, I'll need the tuner module anyway. So, I bought a SEPST and had a tech who knows what he's doing do a smart tune for me. Two hours labor. Can't beat that.
Keep in mind, the bike is bone stock. I had a before and after dyno run done, just to see what happened. AFR dropped to the mid-13's, and from about 1,500-3,500 rpm I picked up between 4-5 ft-lbs of torque and 2 hp. Decel popping is gone. Throttle response is enormously better!
Bone stock, just a quick tune. I'm a happy camper.
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Club Member
Joined: Jul 2014
Posts: 11,469
Likes: 3,572
From: Idaho
Wait, let me add something just to make sure we're clear on an important point.
A "dealer download", particularly in California, will make sure your bike stays in stock tune if you make some mods. It probably won't make your bike non-EPA compliant.
I used the SEPST and had the bike's tune changed to make it run as well as the engineering team knows it can, and it is absolutely no longer EPA compliant.
A "dealer download", particularly in California, will make sure your bike stays in stock tune if you make some mods. It probably won't make your bike non-EPA compliant.
I used the SEPST and had the bike's tune changed to make it run as well as the engineering team knows it can, and it is absolutely no longer EPA compliant.
Elite HDF Member
Joined: Aug 2013
Posts: 3,789
Likes: 277
From: Hawkeye state
Actually it spends a lot more time than you think that lean and leaner, which again, you can see on the dyno. Here's the target afr map for an 07-11 dyna stage one right out of the super tuner. Way too lean, way too often, and you can bet the stock map is only worse. This is one of many reasons why a canned map isn't ok either. Just because it's the target doesn't mean that's where it's running either. If the ve tables aren't perfect it can't hit the target, so a lot of times it's leaner than that with a stock map or canned map.
