Saturday, 11 September 2010

Steve's "Air Trike"

A few days ago, Steve Ellis, another British resident of Assen got in touch and told me about his experimental "air trike" - a Sinner Comfort modified with the chain only turning a propeller on the back, and with no drive through the wheels.

Of course I had to go and take a look, and a test ride.

It's a strange experience. Initially there is very little resistance to the pedals. While at a standstill, the propeller is very inefficient and it takes a while to get moving. However, once you're moving the system is quite a bit more efficient and a reasonable speed can be maintained.

I know that Steve has some other ideas in mind, so I look forward to future developments.

Update: Steve's later developments can be seen here


townmouse said...

this would make a brilliant amphibious bike ... obviously it would need to float first but once the drive's been detached from the wheels that would be fairly easy to achieve

Frits B said...

Any domestic ventilator keeps its propeller in a cage and this man rides around with a live hedge cutter behind his back? Weird people, inventors. Utterly irresponsible, too.

greenobike said...

Is this the design concept? See link.

Anonymous said...


Now he just needs to add the ability to vary the pitch of the blades to improve the top speed and make for easier starts!

Paul Martin
Brisbane, Australia

Michael S said...

Looks cool. But what is the basic advantage of this technique? At first glance it seems to me, that it has a lot of disadvantages, so there must be a reason apart from the coolness factor.

David Hembrow said...

Michael: It's difficult to find a real advantage - it's really just a bit of fun.

It's a proof of concept of sorts. And it's good to see how much it agrees with the theory surrounding propellers. At a standstill you do little but make the air turbulent, but as soon as you start moving it becomes very much more efficient.

However, it'll never be so efficient as simply driving the rear wheels with the chain.

Frits: It is potentially quite dangerous, but don't worry. We were careful, looking out for when other cyclists or pedestrians appeared. It's not about to be ridden through the centre of the city.

escalante blogger said...

Wow! that's a new style of a bicycle.

Anonymous said...

I reckon the vans would give you a bit more space!

Mark Garrett

Simon said...

I think it demonstrates just how much an effect wind can have on a bicycle.

Anonymous said...

Steve is a genius and this looks like a very fun and inspiring bike.