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For those of you who have done the Barons or Scootworks Pulley upgrade, have you noticed a difference in your MPG as well? What was the difference?

Thank you!
 

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51mpg is what I get. highway and city intermixed I have both pulley.
 

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For those of you who have done the Barons or Scootworks Pulley upgrade, have you noticed a difference in your MPG as well? What was the difference?

Thank you!
@shocker92
I have replied 51MPG this morning. Actually it is a little more than that. 53.4MPG as it turns out. :) Because when in put Barons or Scootworks your odometer will be off by 8.8 miles every 100 miles. (Your bike will make +800 miles at 100,000 miles on odometer).

On this Sunday ride I've measured exactly what the MPG is and vido-taped what I did. So you can see what the gear ratio is like, what the acceleration is like and what MPG I get and how I did the measurement. Hope this helps to clear up some cobwebs and myths. https://youtu.be/fAE3CcMSE3A:camera:

Before the pulley upgrade I was getting about 48mpg measured against odometer.
 

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Interesting. I will try and watch the video tomorrow when I have more time.

I for some reason am getting around between 40 and 43 mpg. I do mainly highway riding so between 55 to 85 mph. I also have the custom so I wonder if that makes a difference because it looks like you have the classic. I also noticed that you have the batwing so maybe that helps too.
 

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I am planning on going on a trip that will have me doing almost 8 hours of riding for 2 days straight. Debating on if I should get these, so I was mainly wondering if they would end up paying for themselves gas savings wise but it doesn't seem like that would be likely. Well at least not until like 40,000 miles.
 

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I am a software engineer. Not air-dynamics specialist. Not sure if batwing helps with the MPG. It does make a lot of difference for me, braking the wind, I am less tired riding longer distances. Also I have beetle-bags, those are very air-dinamic but they have bigger profile than stock leather bags. I weigh 180lbs at 5'6" That might make some difference. As far as I know classic and custom have same engine and transmission. Custom might be a bit lighter... ...But I am not 100% sure. I confess I did not research custom all that much. I have both front and back pulleys, no engine or gearbox modifications, no fuel system modifications either. I ride in hilly areas, city, highway and freeway, so I get to 80mph. No power loss in my case, just long "legs" and more options when choosing gears playing with power-bend.
 

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I am planning on going on a trip that will have me doing almost 8 hours of riding for 2 days straight. Debating on if I should get these, so I was mainly wondering if they would end up paying for themselves gas savings wise but it doesn't seem like that would be likely. Well at least not until like 40,000 miles.
Mod will no pay for itself in gas. It will pay in fatigue reducing factor and enjoyment. Less RPM = less high-frequency vibration. The change in final drive is 11.6% so you cruise rather than race. It is a different bike after the mod for sure. These bikes were designed for riding around town, but this mod turns them in to long distance highway cruiser. (B in "Classic B" stands for "boulevard")

If you decide to do it, make sure your rear wheel properly aligned and belt has proper tension. If not, it will squeal and eventually shred your belt in to ribbons. If you do not have tools and "know how" to align the wheel have a proper shop do it for you. Else you will be on the market for a new belt in no time. And those belts are somewhat rare.
 

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With a Barons front pulley and oversize rear tire I think I lost about 3 mpg on average. More if I do a lot of higher speed uphill pulls and I find myself with almost wide open throttle on a slight uphill highway if its windy at all. Well worth the lost mileage for me and on real long hills I don't mind going a little slower and shifting down just to not feel like I'm lugging or overworking the motor.
 

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"and oversize rear tire" that is quite a change in final drive.
It corrects the speedometer perfectly which in my case was 6 MPH. My speedo used to read 70 MPH but I was only actually going 64 MPH. Now at 70 I am actually going 70.
 

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Yep. The speedo is off on these bikes. At least on US version. In my case two pulleys has corrected the problem. Slightly over-corrected it even. After 70mph I get +1 on speedo vs GPS.
 

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I have just the front pulley and GPS shows its correct now which slowed down the speedometer by about 3 at 55mph. But I'm still getting 50 mpg so it helped mine a little I guess.
 

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I do mainly highway riding so between 55 to 85
at 85 mph you are worried about fuel mileage ?????,
 

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at 85 mph you are worried about fuel mileage ?????,
That is an excellent point by the way. The faster you go the thicker the air. The thicker the air the more work one needs to overcome it, thus more fuel to burn.

The aerodynamics drag formula is as follows:



  • Speed u,
  • Fluid density ρ,
  • Viscosity ν of the fluid,
  • Size of the body, expressed in terms of its frontal area A, and
  • Drag force FD.

Basically in terms of horsepower the first 100mph is much cheaper than then next 100mph on top of the first. In other words, if you ride faster than 65mph your fuel economy goes out of the pipe. Once I cross the mid RPM range in fifth gear I no longer wary about fuel economy. There isn't any.
 

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yep .... on my tractor trailer, 50% of the fuel is used to move the air, the other 50% is used to move the unit and the load.
 

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Since we are talking about VN900 which does not have a tachometer. Hard to tell. However if you know what RPM the stock setup gives you at a given speed in a given gear I can give you numbers with which you can calculate the difference:

The front pulley is +2 teeth, rendering a 34 tooth pulley. Changing only the front pulley will change the final drive ratio from 2.0625:1 to 1.941:1. This yields a 5.9% reduction in final drive ratio.

The rear pulley is -4 teeth, rendering a 62 tooth pulley. Changing only the rear pulley will change the final drive ratio from 2.0625:1 to 1.9375:1. This yields a 6.1% reduction in final drive ratio.

Changing the front & rear pulley will change the final drive ratio from 2.0625:1 to 1.8235:1. This yields a 11.6% reduction in final drive ratio.
 

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I provided the RPM / indicated speed back in April:

"I'm running the OEM Kawi tach, and it shows 4,000 rpm when the speedo indicates 120kph, or 75mph in 5th gear."

That should get you started. Mine's a 2012 Custom, not that it matters.
 

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Thank you @Shadow01 with this information we can calculate that at 75mph in 5th gear
With front pulley only:
4000 - ((4000 / 100) * 5.9) = 3,764RPM

With rear pulley only:
4000 - ((4000 / 100) * 6.1) = 3,756RPM

With both front and rear
4000 - ((4000 / 100) * 11.6) = 3,536RPM

Thank you @Shadow01 for providing the key info. Now we know.

Thus with front and back pulley you will go 83.7mph at 4000 RPM
 

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One more thing. According to specification VN900 engine produces 37 kW at 5,700RPM. (49.61 hp).

Pop quiz: Using information listed in above posts how fast can this bike go at 5,700RPM if you have front and back overdrive pulleys? :)
 
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