Hella FF500 vs. FF50's decrease in fuel mileage by how much on GS?

You guys are really forgetting about Newton's principle of action/reaction. Consider that light exerts a quantifiable force projected <i>forward</i>, and you'll realize that the larger the lights, the more reactive reverse thrust you'll experience. This ignores the effect of static and parasitic drag, of course.

The large Hellas give off more heat. I would assume the heat would reduce the aerodymic drag enough to equalize the fuel demand.

But you've failed to factor in the fuel burned thru increased generator drag from the higher wattage demand.

I thought the "new" alternator geaseless bearings resolved that issue?

i heard he ran helium to reduce weight....

Perhaps on the 1200, but doesn't the 1150 still have the old style?

I thought both the lights ran the same wattage bulb ?

To hell with mileage, if nothing else the covers for the FF500's make great serving trays around the camp fire and double as frisbee's for hours of entertainment.

Well I have these on.

Silicone implants gone wrong? :huh

Not really. There were two reasons for using these lights.

1) We used these lights to test the light bar we developed.
2) They have dual lights in each. A city light and main light. They are switched to the low beam and the city lights get turned on when the low beam is on. For serious lighting, I turn on the main lights.

Nice set up! Looks great!
You have enough light for every need and frisbies for disc golfing!

I went with the FF50s...well cuz they were hella cheap.

Get it? "Hella" cheap.

nyuk nyuk. Thanks, I'll be here all week. Don't forget to tip your waitress.

However I did notice a remarkable improvement in economy by going to a K&N and being gentle with the happy handle.

That's a myth. I think the real reason is because with all that draw and the extra parasitic drag, the engine is working closer to the power band, and is much more efficient.

When I was crossing Germany on my VFR two up with luggage, mileage was better if I cruised at 185 kmh instead of 160 kmh. No shit. Just gotta find the motor's sweet spot, I guess...

PIAA's were on the bike when I bought it. Believe they were 520's. Used 85watts/side. But with the mighty Bosch power station churning out 700W who's counting?

Given the feeble glow of the stock shiners, I'm glad they were there -cue for rant- What's the deal with modern headlights, anyway? Why do they almost universally suck? When I was your age..... The 7" round Bosch lamps on '70's BMW's (exact same unit used on mid '90's S1 Buells, btw) with a 100W highbeam would melt the paint off road signs. Well, okay, I'm being hyperbolic (we're talking headlamps here; hyperbolic, get it?) but they'd clear a fast lane of dosey 'righteous defenders of the speed limit' faster than you could say "It's the pedal on the right, you MORON!"

When I rebuild what's left of this bike, think I'm gonna hang a 7" round bosch lamp on it with a good old 55/100w H4 night blazer. Mutter mutter mutter....

Let's not forget that the bigger the light and the higher the heat output the harder it is for a cop to get a laser speed reading on you. Car and Driver put a Hella 1000 with an infrared filter over it on a car in a test and made it nearly impossible to get a laser reading.

But that just goes back to the foil on the mirrors and turn signals. Way less work to wrap that around than replace the lights dont yea think.

I think one thing we did not take into consideration with the gas mileage on BV's bike is the exhaust system. That system does tend to put out a higher amount of BTUs that increase the boost pressure of the exhaust in a forward motion, mutch like the afterburners on a jet. So when you look at the charts and the crossing y-z vector and calculate that with the approx cross winds that they generaly have in Ottawa (that data is available from the local weather service in his area) and when figuring the proper formula it is quite clear how the increase in gas mileage was obtained. Its all just very simple formula and math.

Didn't I hear somewhere that the GS Adv. was used as the stealth bomber prototype? Dead ringer, eh?
Ron

I never got a chance to find out before it threw itself down the road after I fitted Bridgestone Trailwings. Those things orta be against the law.

btw, Your avatar's a hoot.