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Old 04-25-2014, 03:46 AM
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BarelyAWake BarelyAWake is offline
Motorized Bicycle Elite Member
Join Date: Jul 2009
Location: Maine
Posts: 7,212
Default Re: Getting Aero - Speed Gains

Originally Posted by lowracer View Post
...I draw inspiration from the Shell Eco Marathon races held each year and the vehicles people produce that yield super-high fuel economy numbers using very small gas engines, super low drag coefficient lightweight bodies, and a bit of ingenuity. Lets face it, gasoline isn't going to be around forever, but probably longer than anyone reading this. Many get into our hobby because they think it would be cool not to have to pedal anymore, some because they lost their ability to license & register a motor vehicle, some cause their spouses won't let them buy real motorcycles, etc..., there could be a vehicle created on this forum capable of most of the necessary attributes for daily commuting to replace the car?
1- weather protection (rain, cold, sun, snow) accomplished by fairings
2- visibilty/safety/stability (again fairings & trike platforms)
3- fuel efficient / aero efficient (fairings)
4- easy of entry & exit + clothes staying clean (raised seating position trike, wheel & under body fairings)
5- exercise (pedal assist)
6- low noise (well muffled, or electric)
7- etc...
BarelyAWake, I'm still leaning towards a tadpole trike like you have (stability), with a few fairing mods to add weather protection, keep the clothes dry/clean & of course fuel/aero efficiency, as well as the visibilty factor (You're gonna see a huge colorful aero shaped teardrop rolling down the road!)...I think front & rear suspension would also be a huge benefit for the everyday commuter vehicle. The Shell Eco Marathon vehicles are all about lightweight & don't incorporate suspension or cabin comfort to try & win their respective prizes.
I also look to the students participating in the Eco Marathon races for inspiration, their fresh perspective offering unique ideas & advancements - while I'd go a different route in construction materials, the hydrogen powered vehicle below offers quite an interesting body design, one although not the most areo - looks to be quite comfortable & simple to build and is another style on my "considering" list lol;

Even aside from the better control a suspended vehicle offers on rough surfaces I'm of the opinion suspension is a near-must with motorized recumbents in particular, as it's not possible to absorb sudden jolts with your knees like when riding an upright. Without this ability a hard enough bump can cause you to leave the seat, even if momentarily this can cause control issues or at the least, be somewhat unnerving & uncomfortable.

Having said that, I've not had any serious cause for concern with mine, suspended as it is. I would suggest shocks with some sort of bound/rebound control/dampening as the typical, basic coil-overs offered on some recumbents could result in more bounce then without shocks at all, particularly with the added weight of motorization. It confounds me that many of the oh-so-pricy factory recumbents often come with such low-end, basic shocks, they're often oversprung as well as although a trike does weigh a bit more then a bike, it has three shocks instead of one or two... I'm actually "oversprung" (much to my surprise) with my RockShox Monarchs, but as they're air it's not an issue... anymore lol

As you're considering a suspended tadpole, I thought I'd pass along this lil gem - when I was first considering building a tadpole trike fully suspended ones were very rare, leaners more rare still & not perfected. In the time I spent during R&D I decided to forgo the leaner aspect as there were still high speed stability issues and no relevant fully-suspended leaners existed to use as examples - I had my hands full with other design challenges in any case.

There's been a number of advances meantime, fully suspended taddys are now almost commonplace & Steintrikes for one has stepped up to the challenge of a fully suspended leaner - while perhaps difficult to redesign to a motorized chassis and more difficult still to velo, this is quite an interesting platform to consider... if this was a couple few years ago or I wasn't as pleased with the 'T3' as I am, I'd be seriously contemplating this for a project;

vid, leaner in action:

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