Why is tuning a bike so difficult ?
Elite HDF Member
Joined: Nov 2010
Posts: 3,846
Likes: 173
From: Simi Valley, CA
I disagree. The auto tuning only addresses the VE tables via the stock O2 sensors (or widebands if you pay extra). Yes, there's some timing functionality, but not many people go that deep.
Anyway, a dyno tune tunes the bike to conditions that day, period. There's some benefit in having multiple tunes and/or doing periodic VE checks as the bike ages. You can still save and use the tune you paid for, and use the work done to adapt a map to various conditions.
Anyway, a dyno tune tunes the bike to conditions that day, period. There's some benefit in having multiple tunes and/or doing periodic VE checks as the bike ages. You can still save and use the tune you paid for, and use the work done to adapt a map to various conditions.
Tourer
Joined: Jun 2011
Posts: 335
Likes: 5
From: Vermont
I don't have a PV although I do have a PCV w/AutoTune. I'm perfectly happy with my bikes performance after dialing-in my map with the Autotune.
But now in your case, if you had the bike tuned by Jamie, running the autotune seems like a contradiction to me...
Consider this. If you change the map based on the autotune values, then the money you spent having it dyno tuned was a complete waste. You could have just as easily ran the autotune a few times with your starting point being the canned map and came up with the same final result.
Seems to me that one should select and invest in one or the other, dynotune or autotune. Doing both is a waste of time and money.
But now in your case, if you had the bike tuned by Jamie, running the autotune seems like a contradiction to me...
Consider this. If you change the map based on the autotune values, then the money you spent having it dyno tuned was a complete waste. You could have just as easily ran the autotune a few times with your starting point being the canned map and came up with the same final result.
Seems to me that one should select and invest in one or the other, dynotune or autotune. Doing both is a waste of time and money.
I had the 107 kit installed by Fuel Moto in July at their shop. Jamie did the dyno tune. What I was wondering is there any benefit to me running auto tune now after riding the bike for a month. The bike runs great, but I'm always looking for better!
Ultimate HDF Member
Joined: May 2008
Posts: 7,439
Likes: 884
From: 'Noke, VA
If you want to go as far as creating different tunes for different conditions, again, why would you pay for a dynotune first? Create your various maps using the autotune. I still stand by my original recommendation to either dynotune or autotune, not both. And if you decide to do both, it's no harm other than the money you just wasted on the dynotune.
The autotune (which isn't really "auto tune") only effects the VE tables.
Grand HDF Member
Joined: Jun 2007
Posts: 4,599
Likes: 421
From: Lansing mi
You have a good point. On my 2 Sportys I had, 1 air kit $150, 2 jets $7, install my self, done. My newer Harleys with FI have some great advantages, but way more pricey to do a stage-1.
Extreme HDF Member
Joined: Nov 2007
Posts: 14,670
Likes: 139
From: East of the Sun, West of the Moon
I agree with this to an extent. Keep in mind that that any tuning device that writes a map to an ECM will over time develop "learned" values via the AFVs. Sometimes those are for the best, but as I've found out on a couple of different bikes, sometimes it's not so you have to go in and reset those AFVs.
I disagree. The auto tuning only addresses the VE tables via the stock O2 sensors (or widebands if you pay extra). Yes, there's some timing functionality, but not many people go that deep.
Anyway, a dyno tune tunes the bike to conditions that day, period. There's some benefit in having multiple tunes and/or doing periodic VE checks as the bike ages. You can still save and use the tune you paid for, and use the work done to adapt a map to various conditions.
Anyway, a dyno tune tunes the bike to conditions that day, period. There's some benefit in having multiple tunes and/or doing periodic VE checks as the bike ages. You can still save and use the tune you paid for, and use the work done to adapt a map to various conditions.
Ultimate HDF Member
Joined: May 2008
Posts: 7,439
Likes: 884
From: 'Noke, VA
I agree with this to an extent. Keep in mind that that any tuning device that writes a map to an ECM will over time develop "learned" values via the AFVs. Sometimes those are for the best, but as I've found out on a couple of different bikes, sometimes it's not so you have to go in and reset those AFVs.
Extreme HDF Member
Joined: Nov 2007
Posts: 14,670
Likes: 139
From: East of the Sun, West of the Moon
very true.. guess I should have included that.. sorry.. but sometimes that 5% does make a difference..
Ultimate HDF Member
Joined: Dec 2010
Posts: 7,776
Likes: 2,252
From: wet coast BC
good info but where did you get it from. I have seen claims of 15% and a fixed number of cells.
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Extreme HDF Member
Joined: Nov 2007
Posts: 14,670
Likes: 139
From: East of the Sun, West of the Moon
But those with more knowledge on the subject will step in and correct me if I mis-stated..
Ultimate HDF Member
Joined: May 2008
Posts: 7,439
Likes: 884
From: 'Noke, VA
Well, in closed loop the amount/percentage (up to 5% was always my understanding of the ECM's abilities) of "adaptation" is determined by the range of the narrow band 02 sensor's measurement and can be applied to all cells that are considered closed loop cells. Doesn't mean it will, just that it can. I don't know much about open loop tuning but since it can use wide band sensors I would expect the same to apply.
But those with more knowledge on the subject will step in and correct me if I mis-stated..
But those with more knowledge on the subject will step in and correct me if I mis-stated..
This is why I keep telling people that tuners that disable or disconnect the O2 sensors are not a good solution, and that the key to having a bike run the way it should is making damn sure the VEs are exactly where they should be. This allows the AFVs to do nothing more than compensate for atmospheric conditions, fuel quality, and your air filter getting dirty (yes, that really does make a difference).
Last edited by '05Train; Aug 7, 2013 at 09:33 AM.