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[JDOFLHRIDER]

I was wondering what hp/tq =mpg  and ac,pipes and cams were used to get the hp/tq=mpg on their bikes.Riding style might also be helpful .(real hard,hard,reg.,mild,scared of bike)Thanks jdo

[CVORick]

Is this supposed to be a formula you have seen somewhere?  100HP/100Tq=1 MPG?

[JDOFLHRIDER]

Nope I see dyno sheets posted that are hard to read with no mention of mpg's and thought instead of copying dyno sheets members could post max numbers and fuel mileage ,combination of cams ,pipes and a/c. Maybee to help future upgrades of others . Thanks jdo

[grc]

Nope I see dyno sheets posted that are hard to read with no mention of mpg's and thought instead of copying dyno sheets members could post max numbers and fuel mileage ,combination of cams ,pipes and a/c. Maybee to help future upgrades of others . Thanks jdo

Between you, me, and the fencepost, listing max numbers is a waste of time and effort.  And they won't have much influence over mpg unless you measure mpg at wide open throttle.  Mpg at steady cruise, when the engine is tuned properly, doesn't change drastically from stock until you start twisting that right grip.

The important thing on the dyno sheets isn't the max numbers.  The important stuff is the shape of the curves and the rpm range that correlates to the "fat" portion of the torque curve.  The actual graph remains the best indicator of how a particular combination will run in the real world, not just two numbers which can be easily influenced by the equipment and the equipment operator.

I agree that it would be nice if all the posted sheets actually listed the mods, and some do, but if they don't the person posting the sheet could easily add the information.


Jerry

[JDOFLHRIDER]

I  know people ride different and tq/hp locations on chart make a difference,and I was looking to see if a lot of hp/tq = less throttle or less effort to maintain speeds or motion would make more mpg .I just figured that if enough people put up numbers their might be a pattern.We all don't race around like my favorite NY er  (hoist)   lol.

[erniezap]

I have a 124 with about 135/135 that gets about 185 miles per tank with no issues (36-37 mpg)

[SCRM-R]

Mine is a 117 with 125/125 that gets 37-38 mpg.

[Twolanerider]

The red bike sees reported results in the 120/120 range.  It gets about 35 mpg.  Or 30.  Or 38.  Depends on how I ride.  Requesting to see a correlation here to things that aren't in a fixed relationship.

[FUZZNUTS]

The red bike sees reported results in the 120/120 range.  It gets about 35 mpg.  Or 30.  Or 38.  Depends on how I ride.  Requesting to see a correlation here to things that aren't in a fixed relationship.

Don, With just the pipes tuner and mild cam upgrade I'm in the 100 \ 100 range w / 36 to 38 mpg range.......Fuzz

[Twolanerider]

Don, With just the pipes tuner and mild cam upgrade I'm in the 100 \ 100 range w / 36 to 38 mpg range.......Fuzz

Both the red bike and the other red bike here will both cruise down the highway with the cruise on at 75 and get around 35.  Two totally different motors with significant differences in performance and tune. 

SERG is a little heavier.  Catches more wind since it almost always has the king tour pak on.  I play with the SEEGs throttle more.  All the incidental factors come in to play. 

[GregKhougaz]

Good thread!  About time we talked about real world performance instead of just peak numbers.  Jerry said it very well, above.  I'm no expert but here is a recent experience:

I originally went with a HD heavy breather, Dynalink ecm upgrade and tune, drilled cat and 2" fullsac muff cores.  After lots of reading and discussion with Steve at Fullsac, I went with the Andrews 54 CAM and swapped out to a Cat-less header pipe.  Steve also recommended a thinner head gasket which I had installed for a (very) slight increase in compression.  After re-tune, the bike "mapped" at 106 HP and 116 ft lbs.  Best, it's a very flat torque curve with  over 105 ft lbs between 2,400 and 5,200 rpms and the 110 peak at 3,700.  Does not sound like I'm going to keep up with some of the bikes described above but.... 

This month, I rode from Los Angeles to Lake Havasu with three other bikes mostly cruising at about 75 mph, also went through Kingman AZ, Boulder City and Laughlin, NV.  For the trip, I averaged about 47 mpg.

The other bikes (all with batwing fairings and lowers) were:

1.  2008 SEUC with ventilator a/c from my SERG, fullsac 2" cores, no cat and power commander,
2.  2010 Ultra LTD, with power commander and V&H Power duals and
3.  2006 or 7 Ultra with a 96"  (five gallon tank) with power commander high flow and Rinehart true duals

At each gas stop, about 165 miles, I would need about 3.5 gallons; the '08 about 4, the '10 about 4.2 and the Ultra 4.5-4.7.  We were all impressed by the more than a 10 mpg difference.  We did not race but the SERG certainly pulled harder up highway on ramps.  Have to think my set up was more efficient but also the SERG fairing is more aerodynamic.  I was the only one without lower fairings.  We all had tour paks.  Ride on. 

GK

[Sklywag]

On my 06, with the original 103 motor dyno'd at 94hp 101tq it got 38 to 42 mpg.  With the new motor at 104hp, 114tq it gets 38 to 42 mpg.  Good comparison since I didn't change my riding style.

[HD Street Performance]

As far as coreleating parts choices with mileage there are some generic rules of thumb especially when it comes to camshaft choice but the mileage and torque as measured on the typical chassis dyno has no bearing or supplys no data to determine what the MPG expectations or result will be. You will get many folks give empirical data but their loads, conditions, riding styles, and the motor builds are all different. Very dicey data and nothing to do a case study on that's for sure.

Real world testing is done with equipment that can measure BSFC. This is not done in the dynojet world that I am aware of. That said what we see in a dyno chart is a snippet of what the motor does with the influence of the chassis included at WOT only. We see no steady state running and what could be compared to freeway roll-ons for example. Measuring dynamic cylinder pressure and monitoring exhaust temperatures can tell a larger story too. 4 and 5 gas analyzers help technicians that understand what the data means the health and efficiency of the motor and tune. These devices are not normally in the hands of the typical powersport shop and cost well into the 6 digits all combined. These are used by the OEM.

As far as mileage with our machines get, it's mostly about the tune
EFI
What most are doing is setting the VEs in the SEST SERT TTS or Direct link and calling it a day. Most don't test and tune each cylinder and just cut and paste the result from the front number changes to the rear. Mistake number one. If they get the probe in the right spot of the pipe or better yet use wide bands in the pipe bungs (assuming the bike has them) then tune the VEs individually per cylinder this improves the tune considerably, not just WOT but smoothness just riding normally and mileage potential. After the VEs are set the operator can adjust the AFRs and if it is a closed loop bike they can designate which cells will run in closed loop. What those cruise numbers are set to or in the case of the closed loop bikes assuming cruise range is in closed loop what the CLB is set to will be a determining factor in the mileage outcome.

Timing matters!
There are many tuners that don't mess with the timing if they look at a data log and see no knock retard activity. Mistake again. There is mileage and power potential there, in some cases more than setting the AFR properly, but getting the AFRs right is a necessary prerequisite. At cruise light throttle having 40°+ advance is not uncommon and helps mileage by reducing the throttle opening needed to propel the bike. We now have a 2d map that is tied to throttle position or MAP and when the throttle is rolled into from a cruise state to a power state the EFI map needs to drop timing with the number of degrees being progressive  depending on how low the rpms and how high the throttle is opened. Many tuners don't have the auto shop 101, and knowledge of IC engine theory and just have not had the personal experience tuning old carbed cars and bikes to understand what they are doing, which is not just a recipe of what they are taught in a class.

When it is all done at the end of the day it takes just the same power to propel a 1000lb (loaded weight) motorcycle down the road in any given situation when comparing steady states so the power used is the same. The better tuned of them will get better mileage. Of course this is an over simplification and I could get into all sorts of theory and talk on cylinder filling and blowdown and cams but won't bother. Wind and other conditional factors muddy the water too. The guys with the bigger motors have the potential to guzzle fuel when they use the power on tap.

If you want to compare WOT dyno charts good luck. IMO the peak numbers are not all that important. Look at what the averages are from 2k-4k where we ride most of the time. This won't get you the drag race winner but it will get you the happy owners that combined with a good tune and pipe and a proper combination of parts are enjoying their bikes, getting reasonable mileage, and not hurting the motor. IMO and IME "autotune" is a marketers buzzword and we still need dyno tuners, the good ones that "get it" to tune these bikes especially the timing.

[JDOFLHRIDER]

I posted this not for a scienctific or exact numbers more for somewhat of reference to members mpg and hp/tq is the gray area or chits and giggles numbers to go with mpg and also for fun.

[wts]

                          201 hp / 162 tq / 37 mpg

                                             wts