Tuesday, October 2, 2007

Gearing up a Serow

Part of high mileage is getting the engine to turn slower. I am in Illinois where my brother, Bruce has made a 39 T rear sprocket and installed a 17 T front for his new Serow. Pirelli street tires.
Sitting upright, no fairing whatsoever, first, thru 5th gear are just fine. It will maintain 60-65 with the wind but will not hold that speed into wind or up any hill.
This is a good beginning. Anything we get now in mileage improvement will come from streamlining.
Craig Vetter, Designer


Unknown said...


I'm wondering if you have any fuel efficiency data on the Serow before the gearing change, then after the gearing change?

One thing on the smaller road trail bikes which has turned me off is the fuel range. My mate had a WR250 with road tyres which was always running out of petrol between stops. It became the form to stop on the side of the road and siphon some fuel out of one of the other bikes into the little WR. It would be great if a smart looking fairing combined with a gearing change could solve this issue.

Don said...

Royal Enfield used to make a production 350 cc diesel motorcycle that claimed to get over 165 Miles Per Gallon. That is not a misprint. Top speed was 50 or 55 mph (I think). I have web links for this. There is a web site for a home made diesel motorcycle with a hydrostatic drive that claims over 65 MPG at 75 mph with no fairing. My point in all this is: with the low end torque of a diesel and with the availability of bio-diesel (read satisfactory emissions and no, or reduced, eye-stinging aldehydes in the smoke) I see no reason not to use a diesel engine for a motorcycle. It is the transmission that has me stumped. I can find all sorts of data on fuel efficient diesels for this application (such as a Yanmar engine). However, there is little data on transmissions to be found as it pertains to higher MPG. Maybe I'm looking in all the wrong places. Does anyone have web links for transmissions for higher MPG instead of racing performance? I'm too old to outrun cops - I just want higher MPG.

water said...

Oliver Burke here:
I'm converting doing a gasoline to battery-electric conversion on a 1975 Honda CB200T. (to help reduce petroleum's toll on the environment).

I am determined to get superb efficiency, and while I have guys researching motor options and possibly building the controller, I'm in charge of the very important fairing.

If anyone has any hints or tips, send 'em my way! :)

Great site, Craig!


Unknown said...

The Streamliner fairing looks like a very tight enclosed unit. Was there any problem with air for cooling the engine? Down here in central Florida things can get very warm.

The fairings on the 650 kawasaki and the Serow seem to be much more open.

I also saw an article where the USMC use a modified 650 Kawasaki fitted with a diesel engine getting high MPG.

hympg said...

On your website you indicate that it was not worth it to change the jetting on the streamliner.

I was just reading the interview you posted with the 470mpg winner. It seems that one of his team members did some modification of the carb.

Do you plan to make any changes to the carb on the Serow, or do you feel that the stock jetting, etc. is the best set up?