Proof you don't need a tuner
Tourer
Joined: Apr 2006
Posts: 329
Likes: 1
From: Maryland
I thought the whole reason for the new map was to increase fuel mix. Opening up the intake and exhaust allows more air in but it is still mixing with the same amount of fuel right? Does that produce a hotter engine?
Stage I
Joined: Apr 2012
Posts: 1
Likes: 0
From: kansas
I did the vmod on my vrod without any tuners/fueler ect. Its running like a champ. No poping , no less power, Geting the same fuel range also. Plus its not getting hotter that I can tell. But saying all of this I've only probably rode my bike only about 1K miles with the change. Of corse I don't don't want 2 run my bike lean of hot by no means. But just in my opion , I don't think I need a tuner for just for slip ons and stock a/cleaner. Who knows ! I might be wrong.. But probably not .
Road Warrior
Joined: Apr 2010
Posts: 1,739
Likes: 10
From: Suffolk, England
For pre-'07 this was quite correct, if there was more air going in then you had to add more fuel just to maintain the same air-fuel ratio. Then you tended to add more fuel for extra performance over the stock ratio.
Since '07 tho and the provision of O2 sensors, the bike recognises the extra air and adds more fuel, maintaining the stock AFR. So, you will have more air and more fuel without adjustment but it will still be stock AFRs; tuning will then add more fuel for additional performance.
Cruiser
Joined: Jul 2008
Posts: 125
Likes: 0
From: Minnesota
The sensors do exactly what they say they do that is sense. If the bike is running to lean the sensors sense that it is lean and adjust the ECM that is why you have an ECM and sensors. It will adjust itself. The tuners are for race applications and they tweak the ECM wich is crucial when you are on the strip (when it comes down to thousanths of a second). If you do a stage one and you need a tuner than the bike you have is a piece of crap and should not have bought it. You would not remap your car why your bike the same technology.
Road Warrior
Joined: Apr 2010
Posts: 1,739
Likes: 10
From: Suffolk, England
The sensors do exactly what they say they do that is sense. If the bike is running to lean the sensors sense that it is lean and adjust the ECM that is why you have an ECM and sensors. It will adjust itself. The tuners are for race applications and they tweak the ECM wich is crucial when you are on the strip (when it comes down to thousanths of a second). If you do a stage one and you need a tuner than the bike you have is a piece of crap and should not have bought it. You would not remap your car why your bike the same technology.
1. The O2 sensors are accurate over a particular range. Once outside that they no longer function properly. You can get there by increasing the amount of air through the engine.
2. The stock AFRs for cruising and low speed are set lean to meet EPA standards, not for an efficient engine. Running at the stock 14.6:1 will mean the engine runs hot. This is bad for the rider and not optimum for the long-term condition of the engine.
3. If you leave the bike untuned then you are leaving power untapped. That might not bother some people but it does the rest of us. Its our choice to tune the bike for street use to gain the extra power possible.
Road Captain
Joined: Oct 2010
Posts: 724
Likes: 2
From: SC Lowcountry
The sensors do exactly what they say they do that is sense. If the bike is running to lean the sensors sense that it is lean and adjust the ECM that is why you have an ECM and sensors. It will adjust itself. The tuners are for race applications and they tweak the ECM wich is crucial when you are on the strip (when it comes down to thousanths of a second). If you do a stage one and you need a tuner than the bike you have is a piece of crap and should not have bought it. You would not remap your car why your bike the same technology.
Hope your first 100 posts make more sense than this one. What a load.
Tourer
Joined: Apr 2011
Posts: 472
Likes: 2
From: Hutchinson, Ks.
The sensors do exactly what they say they do that is sense. If the bike is running to lean the sensors sense that it is lean and adjust the ECM that is why you have an ECM and sensors. It will adjust itself. The tuners are for race applications and they tweak the ECM wich is crucial when you are on the strip (when it comes down to thousanths of a second). If you do a stage one and you need a tuner than the bike you have is a piece of crap and should not have bought it. You would not remap your car why your bike the same technology.
A cars efi technology is decades ahead that of newer efi scoots. Our Harleys have basically the same level of efi intelligence as the cars in the 80's. If that even. Some do not need tuners. But.....throw a code reader on and see if its throwing lean codes. Mine was. Tuned it and problem solved, along with better power and more of it.
So, even though you obviously know more than anybody about everything, save youre brilliant insight so that the rest of us dummies can have an intelligent discussion. Thankyou.
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Tourer
Joined: Apr 2011
Posts: 472
Likes: 2
From: Hutchinson, Ks.
A few things wrong with that little tirade...
1. The O2 sensors are accurate over a particular range. Once outside that they no longer function properly. You can get there by increasing the amount of air through the engine.
2. The stock AFRs for cruising and low speed are set lean to meet EPA standards, not for an efficient engine. Running at the stock 14.6:1 will mean the engine runs hot. This is bad for the rider and not optimum for the long-term condition of the engine.
3. If you leave the bike untuned then you are leaving power untapped. That might not bother some people but it does the rest of us. Its our choice to tune the bike for street use to gain the extra power possible.
1. The O2 sensors are accurate over a particular range. Once outside that they no longer function properly. You can get there by increasing the amount of air through the engine.
2. The stock AFRs for cruising and low speed are set lean to meet EPA standards, not for an efficient engine. Running at the stock 14.6:1 will mean the engine runs hot. This is bad for the rider and not optimum for the long-term condition of the engine.
3. If you leave the bike untuned then you are leaving power untapped. That might not bother some people but it does the rest of us. Its our choice to tune the bike for street use to gain the extra power possible.
Road Captain
Joined: Oct 2010
Posts: 724
Likes: 2
From: SC Lowcountry
That is exactly what I experienced. I installed XIEDs on my stock 2010 FXDC to richen things up & cool the motor. Ran noticeably cooler & better low end throttle response. Added some Rush Slip-ons (1.75 baffles) & immediately had a decel pop that I just couldn't live with. So....I installed a Ness BS & Dobeck TFI injector tuner. Added a tick more fuel & the decel popping disappeared. Bike runs fantastic & noticeably cooler than when it was stock.