How much will your does your MPG suffer by mods?
Tourer
Joined: Aug 2010
Posts: 358
Likes: 2
From: Swansea,SC
If it is tune then I guess someone needs to show me what the heck I am doing wrong on my 96 with my PV. I have screaming eagle intake, Dragula pipes, and Andrews 48 cams. I get about 33. I do get on it every now an then but not often. Anyone wanting to ride to SC and give this a whirl just let me know. Beer stays in the fridge.
Last edited by Rickey; Apr 17, 2013 at 06:45 PM.
Road Warrior
Joined: Dec 2012
Posts: 1,335
Likes: 5
From: CT
If it is tune then I guess someone needs to show me what the heck I am doing wrong on my bike with my PV. I have screaming eagle intake, Dragula pipes, and Andrews 48 cams. I get about 33. I do get on it every now an then but not often. Anyone wanting to ride to SC and give this a whirl just let me know. Beer stays in the fridge.
Road Master
Joined: Apr 2010
Posts: 824
Likes: 2
From: O'fallon IL
If it is tune then I guess someone needs to show me what the heck I am doing wrong on my 96 with my PV. I have screaming eagle intake, Dragula pipes, and Andrews 48 cams. I get about 33. I do get on it every now an then but not often. Anyone wanting to ride to SC and give this a whirl just let me know. Beer stays in the fridge.
Road Warrior
Joined: Feb 2009
Posts: 1,727
Likes: 11
From: TN
[quote=chgofirefighter;11175005]Curious to know for those that have extensively modded their bikes, such as Headwork, Big Bore kits 107, new cams, etc etc on their 103 engine what did you notice on your mpg's?
I know that when you increase the compression, more fuel is being used. Don't know the specific when it comes to extensive motor work. Cam work alone will not cause you suffer much loss in MPG's? or whatever you do, matters?
I disagree. When compression is increased you are getting more hp from the same amount of fuel. If it takes "x" amount of hp to go 60 mph it will take less fuel to produce that same "x" amount of hp. When I increased the compression ratio on my Saltster from 9.5 :1 to 11.3:1 my milage increased by 5 mpg. However, if you are continually running WFO, milage will go domn.
Bwana
I know that when you increase the compression, more fuel is being used. Don't know the specific when it comes to extensive motor work. Cam work alone will not cause you suffer much loss in MPG's? or whatever you do, matters?
I disagree. When compression is increased you are getting more hp from the same amount of fuel. If it takes "x" amount of hp to go 60 mph it will take less fuel to produce that same "x" amount of hp. When I increased the compression ratio on my Saltster from 9.5 :1 to 11.3:1 my milage increased by 5 mpg. However, if you are continually running WFO, milage will go domn.
Bwana
Road Warrior
Joined: Dec 2012
Posts: 1,335
Likes: 5
From: CT
[QUOTE=bwana1;11181311][quote=chgofirefighter;11175005]Curious to know for those that have extensively modded their bikes, such as Headwork, Big Bore kits 107, new cams, etc etc on their 103 engine what did you notice on your mpg's?
I know that when you increase the compression, more fuel is being used. Don't know the specific when it comes to extensive motor work. Cam work alone will not cause you suffer much loss in MPG's? or whatever you do, matters?
I disagree. When compression is increased you are getting more hp from the same amount of fuel. If it takes "x" amount of hp to go 60 mph it will take less fuel to produce that same "x" amount of hp. When I increased the compression ratio on my Saltster from 9.5 :1 to 11.3:1 my milage increased by 5 mpg. However, if you are continually running WFO, milage will go domn.
So just to extend your logical thought.. You increased your compression from 9.5 to 11.3 so you could observe 5 more mpg?? Wtf?
Just kidding..
I know that when you increase the compression, more fuel is being used. Don't know the specific when it comes to extensive motor work. Cam work alone will not cause you suffer much loss in MPG's? or whatever you do, matters?
I disagree. When compression is increased you are getting more hp from the same amount of fuel. If it takes "x" amount of hp to go 60 mph it will take less fuel to produce that same "x" amount of hp. When I increased the compression ratio on my Saltster from 9.5 :1 to 11.3:1 my milage increased by 5 mpg. However, if you are continually running WFO, milage will go domn.
So just to extend your logical thought.. You increased your compression from 9.5 to 11.3 so you could observe 5 more mpg?? Wtf?
Just kidding..
Stellar HDF Member
Joined: Mar 2011
Posts: 3,482
Likes: 632
From: NorCal Rocklin
A properly modded bike should have more power and get better MPG than a stock one.
The drop that most see is either from playing with the extra power, or from badly matched upgrades/inefficient tune.
They come from the factory tuned for emissions, this is not the same as being tuned for the best MPG.
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Road Captain
Joined: Mar 2013
Posts: 625
Likes: 0
From: Greeley, CO
Sounds to me like most of the time people get worse mileage after mods. To me this would be a problem to me as I plan on doing some long road trips. Right now I am getting 48 mpg in mixed driving (mostly city) so I would expect at least low 50's out on the open road. Dropping down to 35 would suck.
How many people out there can honestly say that they are getting at least the same if not better mpg after a stage I?
How many people out there can honestly say that they are getting at least the same if not better mpg after a stage I?
Tourer
Joined: Apr 2013
Posts: 313
Likes: 84
From: Central KY
[QUOTE=12hdrk;11181363][QUOTE=bwana1;11181311]
Following your logic my high-compression race engines should get better fuel economy than they did in street trim. Sorry, it doesn't work that way.
More compression results in more internal friction effect. More power developed by the engine tends to result in more heat losses. The ultimate result is usually more power but with lower fuel economy. The only exception is gaining power from internal efficiencies (such as efficient porting).
More compression results in more internal friction effect. More power developed by the engine tends to result in more heat losses. The ultimate result is usually more power but with lower fuel economy. The only exception is gaining power from internal efficiencies (such as efficient porting).