Royal Enfield "Dreamliner"

[Michael Moore]

There's a copy of the short article on it by Vic Willoughby here:

http://www.eurospares.com/graphics/aero/Dreamliner.pdf

Built in 1956 the data table at the end shows that aerodynamics can have a significant effect even at 30 mph. Many people (probably not here) seem to presume you've got to be going 50-60 mph before getting any benefit from improved aeros.

cheers,
Michael

[ThermionicScott]

This looks good! I've bookmarked it to read in detail this afternoon.

Those of us who bicycle are aware how wind resistance has an effect even below 20 MPH.

[Michael Moore]

My times riding a push bike shows that aeros (my running out of wind) happens at all speeds!

The bodywork in the article was pretty heavy, being from the early days of fiberglass technology. It also had a lot of focus on styling rather than pure performance. But even with those drawbacks (and a very large and vertical windscreen that gave good weather protection but was poor on drag) it still paid off.

cheers,
Michael

[Ironside]

Thanks for posting the article Michael, I was aware of this but I haven't seen the full article until now.

I wonder how much more could have been gained by reducing the frontal area with a recumbent riding position. My own experience showed a significant improvement in everyday use from 90 mpg un-faired to 130 mpg faired . Considering the 125cc spends most of it's time below 60 mph, it's not a bad result.

The other advantage for me is the huge improvement in rider comfort which is mentioned in the article, that alone would make the modifications worthwhile.

Pete.

[minimac]

Thanks for the post. I find this stuff interesting as I'm contemplating an entry into the 2020 Scooter Cannonball. Being limited to a single cylinder 280cc max engine(along with other restrictions, anything I can learn to increase fuel mileage and speed will go a long ways in that competition.

[Grant-53]

I would definitely recommend aero bars and a fairing for a scooter. The trick is in lowering the handle bar height so that your back is parallel to the ground. I have made my own aero bars from end bar grips, aluminum angle stock, and some 7/8" OD tubing. The coast down tests I do show results at 16-17 mph.

[Michael Moore]

The Dreamliner was very much a conventional design of the time with that near vertical windscreen. It appears the design brief was 1) look cool for the article 2) showcase the newfangled glass fiber material and 3) weather protection for the rider. Economy was a welcome result, but not a main design criterion.

I like the closing comment: "Probably the greatest obstacle to the general adoption of streamlining is prejudice -- the enemy of progress, the antithesis of reason." I see a lot of that prejudice is still around 60 years later. There's a lot of similarities between sheep and motorcyclists -- no one wants to get away from the crowd/look different.

I'm glad the article is appreciated. If more of the modern m/c journalists were like Vic I might still have 10-15 magazine subscriptions. But they aren't, and so I've let all but one lapse because I'm tired of reading lifestyle articles or technical articles that are full of very obvious errors (which the journalists have no concern about fixing/preventing).

cheers,
Michael