#1
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Stumped
When I tuned the Fatboy using the SERT and Twin Scan w/Wego I had a pretty good tune and averaged 41-43 miles per gallon cruise.
I have almost the same build on the EG, but a different 2-1. Fatcat header and Supertrapp Muffler, 16 discs and open cap. 37b cams Bigboyz Heads Issue: Got the VE's corrected while tuning at target AFR of 13.2. However, I have not done any smoothing to the MAP. When done with tuning I changed the AFR tables that have AFR set to 14.1-14..2 I have replaced my 02 sensors make sure that wasn't the cause and confirmed free air calibration of the sensors and insuring the pot/s for free air adjustment wasn't vibrating and changing position. I'm only getting 32-34 miles per gallon after getting the VE's very close. The strange thing is fuel usage isn't much different from a target AFR table at a flat 13.2 to the target AFR table you see in the attached spread sheet. This condition has been more pronounced with the current pipe set up over the true dual setup. With the true duals I got fuel economy up to 38-ish. I discussed timing with Russ and I know I could advance it as the bike never pings, but I don't think it will account for 10 miles per gallon. Could it be too much back pressure....i.e. not enough discs? Thoughts and suggestions please. |
#2
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16 discs open is the equivalent of 26 discs. Is that hybrid setup you've got 3" or 4"? If it's 4", you might want to remove a couple of discs.
I still say you'll pick up a bunch in the timing.
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You might be a king or a lowly street sweeper, but sooner or later you dance with the reaper. Make Doof Clenas Fun Again (MDCFA) |
#3
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Measures 4-inch at the disc.
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#4
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Timing can be huge on economy.
It would be hard to overstate that. Timing is hugely important for mpg. Whether that is your issue, I don't know, but it could EASILY make 10 MPG in the right circumstance.
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I'm not saying it was your fault. I said I'm blaming you. Ricky it's only metal, we can out think it..... Simplicate, never Complify http://www.FraZzledEgGs.com Rhetorical Questions.... Who Needs 'em? ... Famous Tripod
Last edited by MrSurly; 05-19-2014 at 12:57 PM. |
#5
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I will remove discs back to 12 as Smart Dave gave as a starting point and bump timing 2 degrees at a time until it pings and see what that gives me.
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#6
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Check for sumping Warren. I don't remember what year your bike is but the o ring for the oil pump pick up for the crank side of the cases was undersized. Harley changed o rings in 08 or so, if you have the original or used a Cometic kit when you did the cams it'll suck air and let too much oil accumulate in the crank side. A few oz. extra oil will hurt your mpg and make you run hotter than you should, it may not show up in the air cleaner either.
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ISAIAH 6:1-9 ____________________________________________ for Dana Separated at birth? You decide
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#7
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With that set up i would bet you need more discs. Don't discount the importance of timing, either. You want it on the verge of pinging then back off a degree or so.
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------------------------------------------------ I know you think you understood what I said, but I'm not sure you realize that what you heard is not what I meant." [
Last edited by Infidel!; 05-19-2014 at 04:35 PM. |
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I'm running 26 disc and a closed cap with the Supermeg on the 120 in my 06 Ultra, I'll get 41 mpg if I keep it below 65 mph and don't horse it too much. When I took it to Dave's I had him install the O2 sensors so the cruise areas could run closed loop, its tuned with the TTS.
The same bike with the same trapp running 16 disk and close cap with a 95" Head Quarters build making 104/100 would get 43 - 45 mpg tuned open loop. Also ran that trapp on the bike with a 95" stock head TW37 build run 15 disk and a close cap, would run 45 mpg all day long.
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06 Ultra Powered by 120" Head-Quarters 2012 GL1800 Hannigan Last edited by msocko3; 05-19-2014 at 03:40 PM. |
#9
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Quote:
2002. I'll check....but I realigned my pump after the build because of a little oil at the air cleaner. I picked up new o rings because I wanted to check them specifically. The new one for the pick up was different from the one I took off and was a snug fit going on. Sumping would kill power, yes? Runs pretty strong.... |
#10
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Quote:
I will add timing as that makes the most sense since it never pings. Not that I'm complaining......I'll clean the discs up and look for soot. Supertrapp guidance is to add discs for rich and remove for lean. |
#11
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I don't know what your timing looks like Warren, but I will share what I have been using. I used to run more at idle but a tuner talked me into trying less timing and more fuel and it's growing on me. Also using the PV and AT-100 and staying in open loop. This setup will consistently do 40 mpg or over on a Streetglide.
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#12
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Quote:
My timing is advanced from that example. But your afr table gives me some ideas. |
#13
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Averaged 39.41 highway/city.
Verified VE's. Made a few minor changes in the cruise area. Leaned out cruise area of MAP to 14.4. Leaned out transient areas of the MAP as well. Added two discs for a total of 18 with open end cap. Advanced timing two degrees, that coupled with a leaner cruise area induced quite a bit of knock. Removed timing based on knock from twin scan. I think I got it. Will have to see what the timing does when it warns up good. |
#14
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I got 42 yesterday.
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Kimber |
#15
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Averaged 42 and some change over the last 6 gallons.
I'm telling ya, after the VE's are right the afr table is where all the voodoo happens. That'll save me a few bucks to ES and back. start and finish afr tables Last edited by vafatboy; 05-25-2014 at 10:50 PM. |
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