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Discussion Starter #1
And I still averaged 53mpg. :) Revs were between 5k and 7k most of the ride. Twisties and some (very little) highway.

Much improved from my mid 40's before the throttle body sync.

Zuke gel seat served well for 100 miles at a stretch (2+ hours of saddle time). But stayed comfy enough all day.

Need to figure out my handlebars again though... sharp pain between shoulder blades after first 2hours of riding that stayed with me through the two days of riding.

If I can figure it out, I'll load the GPS route... lotsa fun through PA hills.
 

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Revs were between 5k and 7k most of the ride.
That's not a hard ride; a hard ride is about 3,000rpm higher than that. 5-7k rpm is the normal operating range for the wee (and I guess the vee too). I've found that range to be the most fuel efficient too; I've taken to riding highway in 3rd, 4th and 5th gear now instead of 6th, and I refill my tank every 300-350 kms instead of every 225.
 

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Discussion Starter #3
The 5-7K was on the straight bits. Twisties were higher :) As was passing big rigs on two-lane country roads. 4th gear is great for passing at 60-80mph.

One thing I did figure out is that my new front tire has my speedo even farther off than before. Used my GPS as my speedo the entire trip.
 

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I've taken to riding highway in 3rd, 4th and 5th gear now instead of 6th, and I refill my tank every 300-350 kms instead of every 225.
Are we to understabd from this that you are claiming better fuel economy in lower gears (as opposed to 6th) on the highway?:confused: How is this possible?
 

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inquiring minds

Are we to understabd from this that you are claiming better fuel economy in lower gears (as opposed to 6th) on the highway?:confused: How is this possible?
want to know. This is fascinating.
 

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Are we to understabd from this that you are claiming better fuel economy in lower gears (as opposed to 6th) on the highway?:confused: How is this possible?
Easy enough; and it made perfect sense after I had it figured out.

My primary bike use is commuting, almost always on the highway where the traffic is speed-limit slow and sometimes dense (in all meanings of the term). When I get a chance to pass, I generally accelerate at full throttle until I'm back at my my cruising speed. I do this anywhere from 30 to 100 times each way.

Accelerating at full throttle in 6th gear puts more strain on the engine, and because it's not breathing as well at the 5,000 or so rpm it's at at that speed, it burns more gas than when it's 1500 rpm higher up in the range where it can breathe freely. It's not so much a matter of rpm as it is of energy efficiency.

Every engine has an optimally efficient speed that it likes to run at. That's why CVTs are so fuel efficient, they keep the engine at that rpm and vary the gear ratio to accelerate.

I think that for the wee's engine, the energy-efficient rpm range is somewhere between 6,500 and 8,000 rpm.

Of course, if you're not going to be at full-throttle, then all bets are off and a higher gear at part throttle will be more fuel efficient.

For me the lower gears/higher rpms work out because I spend enough time at full open throttle that it makes a range difference of around 100kms on a tank of gas. Accelerating at full throttle (if in the optimal efficiency rpm range) consumes 5x the fuel (or more) than maintaining a constant speed; doing this just 5% of the time accounts for 25% of your fuel consumption. IF you're not at the optimal efficiency rpm range when accelerating at full throttle, depending on the fueling system, that 5x increase in fuel consumption can easily turn into 10x, 20x or 30x (as anyone who's ever had a mechanical carburator, especially one with acceleration pumps has eventually learned).

I hope I've explained that well enough. The moral of the story is gear down if you're going to accelerate; it's better for your fuel consumption and it's better for your engine because it reduces the load.
 

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5-7k rpm is the normal operating range for the wee (and I guess the vee too).
Riding at 5K rpm on a stock DL1000 (17/41; 6th gear) will return an indicated 95 mph/152 kph. If we allow for a 5% error, which is my experience, ground speed is still ~90 mph/144 kph.

Even with 16/43 gearing, I'd think that a Vee would still be moving pretty expeditiously if holding it between 5 - 7K, even when not in Overdrive.
 

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Discussion Starter #8
7K on the Wee is around 75mph actual (GPS) if memory serves. 5K is about 60mph ... ya know ... I'm going to have to go check that again. 7K might have been 80mph in top gear. Too busy watching where I'm riding.
 

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And I still averaged 53mpg. :) Revs were between 5k and 7k most of the ride. Twisties and some (very little) highway.

Much improved from my mid 40's before the throttle body sync.

Zuke gel seat served well for 100 miles at a stretch (2+ hours of saddle time). But stayed comfy enough all day.

Need to figure out my handlebars again though... sharp pain between shoulder blades after first 2hours of riding that stayed with me through the two days of riding.

If I can figure it out, I'll load the GPS route... lotsa fun through PA hills.
Really no disrespect, but 5K-7K RPM is not hard riding. At 7K the engine just starts revealing its real power.
And 53MPG reflects that you were mostly cruising.
There is no magic here, just the laws of physics.

I rode this last weekend with SuperSlomo and averaged 45MPG. If I don't ride hard I get 49-50MPG.
When I chase my friend that has a Busa -> 45MPG.
 

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I found that my Wee got better mileage (fully loaded) hammering thru the mountains near Duffy Lake Provincial Park in BC than it did cruising on highways. You seriously burn fuel trying to punch thru the air at high speeds (say cruising at 80mph) that ripping it on twisty roads, even if you hit 80+ here and there, ends up being more efficient.
 

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...

Accelerating at full throttle in 6th gear puts more strain on the engine, and because it's not breathing as well at the 5,000 or so rpm it's at at that speed, it burns more gas than when it's 1500 rpm higher up in the range where it can bareathe freely. It's not so much a matter of rpm as it is of energy efficiency.

Every engine has an optimally efficient speed that it likes to run at. That's why CVTs are so fuel efficient, they keep the engine at that rpm and vary the gear ratio to accelerate.
[ /QUOTE]

Best fuel economy doesn't necessarily coincide with most efficient rpm in a vehicle with fixed gear ratios.

In general pumping losses hurt fuel mileage at high rpms and gas engines are more efficient running at low revs with wide open throttles. (This is actually a part of why diesel engines get great mileage: they don't have throttle plates restricting intake and the lower revs cut internal friction losses.)

If the bike is running at a speed that mutliple gears could be used, and the engine is running at an RPM that it is comfortable running at (in the DL650 generally over 3,000 RPM) then the bike will get better mileage in the higher gear.

I'm sure there are engines with intake tracts that are tuned quite precisely to a particular rpm range that this wouldn't apply to, but I'm also sure this isn't a case with V-Strom engines.

..Tom
 

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Discussion Starter #12 (Edited)
You missed my clarification - 5-7k was only on the straight bits. Twisties was up a good bit higher and it was mostly twisties. My point is - after my tuneup, by MPG shot up a LOT. Especially considering the fact that I wasn't taking it easy. I was out catching sport bikes (story for another post).

So - riding "moderately" hard and still averaging 53mpg ... yeah, that's pretty darn good.

Really no disrespect, but 5K-7K RPM is not hard riding. At 7K the engine just starts revealing its real power.
And 53MPG reflects that you were mostly cruising.
There is no magic here, just the laws of physics.

I rode this last weekend with SuperSlomo and averaged 45MPG. If I don't ride hard I get 49-50MPG.
When I chase my friend that has a Busa -> 45MPG.
-edit-
Nevermind.. I guess my clarification post didn't get posted?? :confused: Yeah - 5-7k on the few straight bits. I wasn't cruising.
 

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7K on the Wee is around 75mph actual (GPS) if memory serves. 5K is about 60mph ... ya know ... I'm going to have to go check that again. 7K might have been 80mph in top gear. Too busy watching where I'm riding.
With stock gearing (15/47) actual 6th gear speeds are
5000 rpm = 62 mph
6000 = 75
7000 = 87
8000 = 99

indicated speeds are
5000 = 67
6000 = 81
7000 = 94
8000 = 108
 

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Discussion Starter #14
Yeah - that sounds about right. :) I knew I was grooving pretty good at 7K in top gear.

With stock gearing (15/47) actual 6th gear speeds are
5000 rpm = 62 mph
6000 = 75
7000 = 87
8000 = 99

indicated speeds are
5000 = 67
6000 = 81
7000 = 94
8000 = 108
 
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