Proof you don't need a tuner
Road Captain
Joined: Aug 2008
Posts: 550
Likes: 8
From: Twin Cities,Mn.
I had a Power Commander on my last bike (FLHRC) and had nothing but problems with it! My local mechanic who has over 25 years of wrenching, building XR 750 race engines etc., told me, and I quote.........."get that piece of **** off your bike!"...........I did........well, I let him do it.........did the simple download, and was a happy camper again! Hate to say this because I know there are a lot of PC users, but I wouldn't have one of those things on my bike EVER again. $350's down the drain, two months of trying to get the thing tuned, dyno runs, three different mechanics from three different dealers, and bike still spit, popped, backfired like crazy. Took it off, dealer remap, and everything ran great. JMHO, but for a simple stage one (slip-ons, airbox) the dealer remap works great. All those SE tuners, PC's, etc. are overkill for a simple stage one, and that's my mechanic's opinion, which I wholeheartedly agree with.
Road Master
Joined: Aug 2012
Posts: 854
Likes: 20
From: CT
I have to chime in again.. and please don't take offense to this.. but you and some other people here are missing the point, and replacing it with another point.
The ECM is capable of compensating for any changes in the fuel mixture up to a certain point, that's caused by an air cleaner or higher flow exhaust. Probably any stage 1 mod you do, the engine will compensate for, bringing the fuel ratio the stock and keeping it at the stock AFR.
This is a fact.
However, the question really is.. is that stock AFR (stock map) that you're running the best for the engine's overall longevity and performance? Is it optimal? No, IMHO.
So do you NEED a download or fuel map? No. Not unless you're doing engine work. Should you WANT a to run a fuel map that will make the performance better and the engine run cooler? I know I would.
The people that say there is no difference are the people that wouldn't notice a difference with it or without, because they're riding style probably wouldn't dictate that they would. if anyone wants to take that negatively.. well.. this IS the DYNA forum (not the softail forum)..
The ECM is capable of compensating for any changes in the fuel mixture up to a certain point, that's caused by an air cleaner or higher flow exhaust. Probably any stage 1 mod you do, the engine will compensate for, bringing the fuel ratio the stock and keeping it at the stock AFR.
This is a fact.
However, the question really is.. is that stock AFR (stock map) that you're running the best for the engine's overall longevity and performance? Is it optimal? No, IMHO.
So do you NEED a download or fuel map? No. Not unless you're doing engine work. Should you WANT a to run a fuel map that will make the performance better and the engine run cooler? I know I would.
The people that say there is no difference are the people that wouldn't notice a difference with it or without, because they're riding style probably wouldn't dictate that they would. if anyone wants to take that negatively.. well.. this IS the DYNA forum (not the softail forum)..
I actually just had a road king come in that's had a 103 with stage 1 with stock map since new, for 16k miles. Obviously the owner seemed to feel the bike ran perfectly fine if he rode it that way for 16k miles, and it's had plenty of time to do all this "self tuning" you guys talk about! Well I got it on the dyno and did some baseline runs and it's the saddest 103 stage 1 I've ever seen. It made terrible, choppy power and started detonating on the 3rd pull once it was warm. It was down 10/10 at least. Made less power than a 96", and I've tuned a 103" with bone stock catted exhaust that killed it too.
No, you don't NEED a tuner for the bike to go down the road, but a lot of people like their investment to run its best. I never have people complain about the price after the tune. I usually hear things like "never imagined it could run this good", "huge difference", "best money I ever spent on the bike", and my favorite, "made me love my bike again and I decided to keep it".
Btw, love all the experience that comes from reading a magazine
Last edited by vdop; Feb 12, 2015 at 06:32 AM.
Outstanding HDF Member
Joined: Aug 2011
Posts: 2,325
Likes: 7
From: SE Illinois
I've had bikes that I've just done slip-ons and a/c, and 2 bikes I've also done cams & 2-1 exhaust.
On stage 1 bikes, I've ran XiEDs, stage 1 download, and eventually had the bikes dyno tuned properly with SEPST. Did they run ok with the XiEDs and stage 1 download...yeah, ok & fine. But...after having the bikes dyno tuned it was night and day difference. Much smoother power delivery, better economy, better power & torque, and I knew by bike was running the optimal AFRs and timing.
With my last 2 bikes I've also done cams. I dyno tuned them when I had the cams done...which IMHO, installing cams is a waste of time unless you're gonna spend the money & take the time to do a proper dyno tune. There is no canned map that is going to be ideal for your bike...every bike is different.
Not bashing anyone that doesn't dyno tune, but for those people that are doing upgrades in order to get more performance out of your bike, why half *** the tune, or worse yet not tune it at all? It just seems silly to me to spend $15,000 give or take on a bike, spend another $2,000 in upgrades, then get all *** puckered when it comes to tuning your bike.
Are there good canned maps available for stage 1 bikes....sure. It is optimal....no.
There is no replacement for a good dyno tune. Period.
For those that don't or won't get their biked tuned properly, you're just trying to justify it because you have not done it. Don't get me wrong, there are some shitty dyno tuners out there, but if you've ever had a biked tuned properly on a dyno with someone who knows what they are doing, you would understand.
I've spent **** ton of money on my bike...and having it dyno tuned properly was the best investment I've made. I know my bikes is running optimal for the mods I've done, and I know my AFRs and timing are spot on & optimal at every rpm.
On stage 1 bikes, I've ran XiEDs, stage 1 download, and eventually had the bikes dyno tuned properly with SEPST. Did they run ok with the XiEDs and stage 1 download...yeah, ok & fine. But...after having the bikes dyno tuned it was night and day difference. Much smoother power delivery, better economy, better power & torque, and I knew by bike was running the optimal AFRs and timing.
With my last 2 bikes I've also done cams. I dyno tuned them when I had the cams done...which IMHO, installing cams is a waste of time unless you're gonna spend the money & take the time to do a proper dyno tune. There is no canned map that is going to be ideal for your bike...every bike is different.
Not bashing anyone that doesn't dyno tune, but for those people that are doing upgrades in order to get more performance out of your bike, why half *** the tune, or worse yet not tune it at all? It just seems silly to me to spend $15,000 give or take on a bike, spend another $2,000 in upgrades, then get all *** puckered when it comes to tuning your bike.
Are there good canned maps available for stage 1 bikes....sure. It is optimal....no.
There is no replacement for a good dyno tune. Period.
For those that don't or won't get their biked tuned properly, you're just trying to justify it because you have not done it. Don't get me wrong, there are some shitty dyno tuners out there, but if you've ever had a biked tuned properly on a dyno with someone who knows what they are doing, you would understand.
I've spent **** ton of money on my bike...and having it dyno tuned properly was the best investment I've made. I know my bikes is running optimal for the mods I've done, and I know my AFRs and timing are spot on & optimal at every rpm.
Outstanding HDF Member
Joined: Aug 2012
Posts: 3,217
Likes: 90
From: Detroit
I actually just had a road king come in that's had a 103 with stage 1 with stock map since new, for 16k miles. Obviously the owner seemed to feel the bike ran perfectly fine if he rode it that way for 16k miles, and it's had plenty of time to do all this "self tuning" you guys talk about! Well I got it on the dyno and did some baseline runs and it's the saddest 103 stage 1 I've ever seen. It made terrible, choppy power and started detonating on the 3rd pull once it was warm.
If what one reads in American Iron should be taken with a grain of salt, should the same standard apply to what one reads in your posts?
Grand HDF Member
Joined: Jun 2008
Posts: 3,983
Likes: 2,144
From: Ohio
I guess the question I'm curious about is this - I think my bike runs great with just the dealer download. It hasn't given me any problems at all (unlike the tuners I've had). I really don't care at all about milking every bit of power out of my bike. I just want a bike that I can ride for many years to come, racking up the miles, without doing any harm whatsoever to the engine because I didn't "tune it" or have a dyno run on it. So.....in your opinion, will those of us who just did a download cause ANY harm, shorten the engine life, or damage the engine in any way, if we don't do anything else? 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.
Elite HDF Member
Joined: Aug 2013
Posts: 3,789
Likes: 277
From: Hawkeye state
I guess the question I'm curious about is this - I think my bike runs great with just the dealer download. It hasn't given me any problems at all (unlike the tuners I've had). I really don't care at all about milking every bit of power out of my bike. I just want a bike that I can ride for many years to come, racking up the miles, without doing any harm whatsoever to the engine because I didn't "tune it" or have a dyno run on it. So.....in your opinion, will those of us who just did a download cause ANY harm, shorten the engine life, or damage the engine in any way, if we don't do anything else? 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.
http://tuneyourharley.com/biketech/content/harley-davidson-closed-loop-ecm-fuel-map-revealed
Road Master
Joined: Aug 2012
Posts: 854
Likes: 20
From: CT
There are occasional complaints like this with factory stock bikes too. All it takes is something like one of the sensors being a little off, such as an oxygen sensor that thinks it's seeing 14.7 when the mixture is actually 15.5, or an air leak. Maybe it's more economical to tune though in these cases than to chase down the real problem.
If what one reads in American Iron should be taken with a grain of salt, should the same standard apply to what one reads in your posts?
If what one reads in American Iron should be taken with a grain of salt, should the same standard apply to what one reads in your posts?
What I am saying has been and will continue to be proven on the dyno and the rider's butt dyno over and over by good tuners across the country. I'm not trying to insult anyone or their bikes or sell anything, I just like to make these bikes perform well and make the riders happy.
Btw, sharkman's post says it all perfectly
Here's your o2 sensors doing their job http://harleytechtalk.org/htt/index....c,79206.0.html
Last edited by vdop; Feb 12, 2015 at 09:54 AM.
Outstanding HDF Member
Joined: Aug 2012
Posts: 3,217
Likes: 90
From: Detroit
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.
Last edited by Warp Factor; Feb 12, 2015 at 10:13 AM.
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Road Master
Joined: Dec 2012
Posts: 848
Likes: 30
From: CO
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.Below, I attached my stock tune. Look at how much of the table is 14.7-14.5 That's a lot. There's practically no difference between 14.7 and 14.5 btw.
Now look at my tuned fuel table. That's what an air-cooled engine's fuel table should look like. I still get ~32mpg with that table too.
Grand HDF Member
Joined: Jun 2008
Posts: 3,983
Likes: 2,144
From: Ohio
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?????
Last edited by hd4evr2008; Feb 12, 2015 at 11:16 AM.