I am disappointed that my 2005 Silverwing has been getting less MPG than when I first purchased it. I purchased it used with 1341 miles on it in July of 2007. I just turned over 16000 miles on my last ride of 240 miles last week. When I first got it I was getting 50 MPG which is what most of you report getting. I did put a 'Givi' wind screen on it and I do weigh 240 lbs. I do not baby it but do not abuse it... I changed the spark plugs and have done all the maintenance according to the book. I do get in the 40 MPG range average now. Does anyone have any suggestions? Yes, I have ran "Seafoam" through it and it does not seem to help. Maybe I need to check the gap on the plugs or something. I runs great starts great etc. and I will be checking the belt as soon as it warms up.
Old Dave in Western Nebraska

Hi Dave,

There are a bunch of things that cause the MPG to take a nose dive. OK, let's start with cold weather. The Silverwing loves hot weather and gets much better MPG when the weather is warmer. Air filter being clean. Tire pressure. Belt wear. Wear on the driver and driven disc plates. The big spring on the driven drive gets weak over time. And last but not least is the gas stations change over to a different blend of gas in cold weather.


Dave...I hope this helps.

There have been a number of posts on this forum about poor fuel mileage just before a belt failure (or some sort of belt problem). If you are at 16000 miles, you are well past the 'expected' service life of the belt. I think you are correct in checking that first. What is your RPM at 65mph indicated? That may also be a clue. As the belt wears, it gets thinner, which causes the RPM to rise, which affects fuel mileage in a negative way.

Winter gasoline formulation, colder weather, and possibly the belt.
It could be one or all of those factors.

Dave, has the change been sudden or gradual? Did the Givi make an immediate difference? How about you... you go from 120 to 240 overnight? Note items Dennis mentioned above. Weather changed in your area? Fuel mix for winter months etc.

16,000 miles on the belt is the recommended change interval. There is a lot of discussion on that subject. From my reading, sudden change in gas mileage would not be expected at that mileage on the belt. If you are inclined to check that out, open the case and examine for wear. If there is excessive dust or belt does show excessive wear, you may have found the problem. You need to thinking about replacement anyway, whether the belt is the mileage problem or not. There is a great pictorial here in the maintenance section. Do a search to find that great help tool.

For any other users in climates similar to Nebraska now. Have you noticed a loss of mileage? My mileage here in Arkansas riding solo has been in mid 50s. With wife up mid 40s plus a spit is common. Weather is just taking the cooler direction. I will pay attention to that and see if the mileage changes for me. I don't believe our weather here changes enough for the fuel vendors to change to winter mix.

Thanks to all of you....I am thinking along the same lines. I did notice a difference when I put the 'Givi' wind shield on it by a MPG or so. I would suppose my 230 lbs plus gear accessories and etc. enters the picture and of course, the belt at the 16000 mile interval, weather change etc. I know HONDA makes a good product and they don't just set the V Matic light to come on at 16000 for nothing. It is there for a purpose and they knew this so that is why they set the light at the building of the fine steed. I think that is where I will start. As soon as it warms up, I will put a new belt on and check the plates and spring etc. I would not trade this for a m/c as it does a great job with out nickle and dimeing you to death. Progressive maintenance is the key....Old Dave

Dave,
I am most sure it is because of the gasoline. Since we have mandated 10% ethanol October till sometime in the spring, I have never had better than 43-45 mpg in the fall/winter/spring. Sometimes in the summer I get as much as 47-48 mpg.

The trike, on the other hand, gets in the mid to high 30's, sometimes in the low 40's. Of course, almost all of the trike mileage has been in or near town. I think it is because I have come close to tripling the frontal area and added the rolling resistance of two fat tires.

Heavy rider and big sail of windshield take away mileage, but does not explain drop.

I have been getting mid 50's with 2 time high of 61----run hard on freeway, always well over 6,000RPM can drop below 50.

So to see if bike can still do 60mpg as it did new (09) I first looked at Air Cleaner element----ok at 12,000 miles, looks like life of 20,000miles with my type of riding.

So took 300 mile trip---kept speed under at 60 mph or less and no real hard throttl use---in other words ridden as scooter should be, not as real motorcycle substitute and of course this type riding = 60 mpg.

Gas formula change with cold, etc.


John Grinsel