What's your best motorcycle MPG?

[Ransom]

Seems my mileage on bike various much more than with car or truck. On my Rocket III I've gotten a low of 28 and a high of 58 mog.

[Daschicken]

Originally Posted by Ransom

Seems my mileage on bike various much more than with car or truck. On my Rocket III I've gotten a low of 28 and a high of 58 mog.

Is that the new 2.5L or the older 2.3L?

[Ransom]

Originally Posted by Daschicken

Is that the new 2.5L or the older 2.3L?

2.3L. T model

[woodsrat]

On a lark I bought a Honda Monkey. Why? I have no idea. It was one of those spur-of-the-moment purchases and the first time I've bought a motorcycle without a specific purpose for it.

Here's where it gets interesting. I rode it around and found it to be a very practical motorcycle and very comfortable. When the opportunity to ride it to Tennessee from Indy came up I jumped on it and covered 776 miles over three days.

So why am I telling you this? Without any sort of attempts at aerodynamics the bike consistently returned 113 to 121 MPH running along at around 50 MPH. On the way home I got off the highway and followed country roads back to Indy. When I gassed up today I found I'd gotten over 127 MPG!!!

If this little bugger does this well with me hanging out there like a sail imagine what could be done with one fully streamlined.

By the way mine is box-stock save for a Takegawa cat-less replica pipe and a Takegawa foam filter assembly that replaces the stock air cleaner element in the stock air box on which I mounted a thicker piece of UNI filtering foam.

I'm still extremely ignorant about how Honda's PGM-FI works (although I'm trying to find and read everything I can about it) but I can say as a matter of fact this system offers incredible fuel mileage.

Somebody build a streamliner and go win a Vetter competition.

[M_a_t_t]

What is the gearing like?

[woodsrat]

Here's the ratios from the Monkey service manual. The Grom/Super Cub and the new CT-125 use the same internal ratios and the primary ratio is almost the same between the manual and auto clutch versions. Only the final drive ratio varies between the small wheeled bikes and the Super Cub. The CT will have three more teeth on the rear for off-road use.

The biggest reason for the taller gearing on the Monkey (lower numerically) is it's 12" wheels.

1st 2.500
2nd 1.550
3rd 1.150
4th .923

Pri. 3.350
Fin. 2.266

[stiletto2]

Is the top speed 50 mph because that is all it has power wise? (wind drag holding it back?) or (is it speed restricted or RPM restricted/limited) or could it go faster?

If it is speed limited I'm not so sure streamlining would be much help. (but I could be wrong about that... it is just my hunch, so...)

If it is RPM restricted/limited, then a solution for better economy might be a bigger front drive sprocket + streamlining... That would also be of help if it was actually capable of more speed simply with the addition of streamlining. Not that one would necessarily want to go faster per se, but rather for the economy gained from being slippery enough to afford taller gearing for lower RPMs at given speeds.

[woodsrat]

Top speed on the Monkey is in the high fifties and I saw sixty-two on a downhill during my trip to Tennessee. Fourth gear is an overdrive and depending on the weight of the rider it can struggle to run that fast. I weigh a buck forty neked so it works well for me.

Folks have already proven that a small bore can achieve better speeds and fuel mileage through streamlining. Starting with one of these motors would certainly put them ahead of the curve because they run a LOT better than the old small Honda motors and get far better mileage to boot.

[skyking]

1981 Yamaha 500 XT
65 MPG running up to the woods, then putting around on forest service roads all day.
It was 1984 when gas was really cheap, too IIRC, it had a 2.2 gallon tank and I could fill up at Whistling Jacks on SR410 so I could get home.

[Charlie Cheap]

I sold my 650 Moto Guzzi SP after an accident but loved riding for 20 years accident free. The wife said she was scared every time my buddy and I went on our spring - fall long rides, so after the accident I went back to 4 wheelers. On the road running at highway speed with full luggage it got 55 - 60 MPG. I made an extended windscreen (about 6" taller), it came with a lower fearing, and I installed the hard luggage from a Moto Guzzi 650 cruiser. It was a shaft drive and designed in their wind tunnel, which really helped in bad weather. I had a 550 Yamaha Vision with full fearing that got great MPG but forgot exact numbers. LOVE 2-wheelers but they scare the wife of 54 years...so I stopped riding back in 95.