Fred's bike use and plans
Note: This page attempts to combine text and inline images on one page which is awkward with "manually maintained" web pages. (I use a text editor to edit html rather than a wysiwyg html editor.) They look ok with my browser with the right size font. But I suspect that is not true with other browsers. The general format of images is images on left margin with "narrow" column of description on the right. To help recognize if it is right, the characters "_|" should be displayed just to the right of the lower right corner of each image. If it does not look right, you may try changing the font size (with >view >text zoom (Mozilla) ). I may have to convert it to html tables to make it more universally well formatted, but that is a pain. Fred I've used a bicycle as transportation all my adult life. I've never had a car that I used on a daily basis. I have usually had access to and used a car for transportation for trips that a bike or public transportation would not serve well. My wife has a car that she uses daily tho I sometimes use it when a bike is not practical. We often use it when we make a trip together. Instead of a second car in my family, I use bicycles. I often bike one leg of a trip and make one leg of the trip with her with my bike in the rack on top of the car. We often use ham radio to coordinate such trips. Sometimes I take my bike on public transit. The Twin Cities buses now all have racks on the front that fold down for two bikes. The Light Rail Transit cars also have bike racks. (As of 3/06 we have one LRT line from downtown to the airport and the megamall.) "Multimodal" use can considerably extend the useable range of bicycles. I ride my bike whenever the distance and conditions are favorable which is quite often, even here in Minnesota and even in the winter sometimes (2005-2006 for example). Usually it is if I am going alone and not too far, up to about 6 miles typically unless a multimodal option is available. Weather is also a factor. I will ride if the temperature is 20 degrees F. or above and the streets are relatively dry and free of ice and snow. Sometimes I'll stretch these criteria - for shorter distances, special needs, if it will warm up later etc. Over the years I've ridden many different bikes. I've seldom bought new bikes. In this affluent society many people buy bicycles and don't use them for long. Often the don't treat them well or maintain them or they move on to something else. As a result there are many used bikes around that are useable or fixable. Sometimes these bikes are sold at yard sales and such or simply discarded. This is the kind of bike I typically ride. At any one time I have one or more of these in rideable condition as well as others that could be fixed. The bikes I use generally have 26"-27" wheels, some mountain bikes, usually have a deraileur for multiple (10+) gears and are upright conventional bikes. I've long had an interest in recumbent bikes ("bents" ) tho I have never purchased or built one. Here's a good overview of Recumbent bicycles at Wikipedia. There is an active group here - MNHPVA ( MN Human Powered Vehicle Association ) of people who build recumbent bikes. As I get older recumbents look more attractive. I have over the years ridden various recumbents for test rides and pondered what design would serve me best. Since bents are much less available used, building a bike is a main alternative for a lower cost. Building a bike also allows one to try various designs and features. I long ago took a welding class with MNHPVA but have never gotten set up to do any building. One main design criteria for me is that the bike be transportable easily on our car, buses and LRT trains. This means that the wheelbase must be similar to conventional bicycles (about 40" between axles). Most "short wheel base" (SWB) "bents" meet this requirement. What follows are pictures of bike from which I'd like to borrow features. March 2006
Canto:
In the summer of 2005 I considered buying
this used Burley Canto recumbent bike.
I took it on two long test rides on nearby
Minneapolis bikeways. I also tried putting
it on our car's bike rack which would work
with a little adaption. I also tried it on
a bus bike rack which worked as is.
It has an interesting feature NOT shown in
this picture. There is a second headset
in front of the cranks so that it can be
set up as a long wheel base (LWB) bent.
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Stealth:
This "Stealth" bike has
a straighter frame that
I find useful (see
below), a full size rear
wheel and a small (20"
or 16" (?) front wheel)
which is useful for my
design.
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Hornet:
The "Hornet"
(from page 34 of
the book _The
Recumbent Bicycle_
by Gunnar Fehlau)
has a straight
frame and under
seat steering
which I find
attractive.
This bike is
fully suspended -
above the forks
which takes some
space and the
rear triangle is
pivoted and sprung.
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Bacchetta Aero:
Another straight frame
tho the larger front
wheel comes too close
to the pedals/feet for
street use (this is a
racer) Note the lack of
suspension and the seat.
From page 85
of the book
_The Recumbent Bicycle_
by Gunnar Fehlau
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Shaft drive bike:
Tho not a recumbent, this bike
made by Dynamic Bikes has a
shaft drive which is very
attractive for it's durability
and low maintenance.
This is the reason for the
preference for a straight frame.
The 3/8" drive is in the ~7/8"
silver aluminum tube with lettering
that goes straight back from the
cranks parallel to the frame
The gear ratio of the shaft is
fixed so a 7 or 8 speed rear hub
is used.
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Fred's bike plan
Below is a sketch of Fred's current thinking for a design for a bike that meets my design criteria. It has not been built tho I would like to. A lot of development work is needed yet. Comments welcome.
o straight, wide frame (red)
see detail below
o "short" wheelbase - comparable
to conventional adult bike (~40")
o ~27" rear wheel
o 16-20" front wheel
o under seat steering (purple)
o shaft drive (parallel
to the frame - green )
o No spring suspension of
wheels
o seat support subframe (blue)
adjusts fore / aft
o 7 or 8 speed rear hub
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The shaft drive would complicate / prevent moving the cranks fore/aft to adjust for rider size as is commonly done on SWB bents. Instead I'd have the seat (actually the whole seat support subframe) slide on the frame to adjust for rider size with the position for me ( 5'-10" ) be close to the rear wheel. The subframe would be clamped very securely to the main frame with sizeable bolts. The sliding seat is common on long wheel base recumbents. Hopefully this combined with the smaller front wheel would allow the cranks to be not too far forward of the front of the front wheel and still have good clearance. Shaft drive would also complicate suspension of the wheels so I would not suspend them. Instead the seat would have springs. I'd like to have a seat back that folds down to reduce wind resistance when on top of the car. On the other hand I 'd like to try a "hard shell" seat as on the Bachetta. Maybe with the seat bottom similar to the Canto. Note that using the shaft drive depends on getting access to this technology. If that proves impossible, a fixed gear chain could be used. Hopefully it could be totally enclosed.
Fred's bike plan - vertical view
o Wide frame (red) made
of two parallel
.75" x 1.5"
rectangular tubes
o Two sides of frame tied
together at cranks, head
tube and by "X" under seat
o Extends behind seat to
support rear wheel
o Unlike this illustration
tubes will bend closer together
starting just behind the front
wheel.
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o Under seat steering (purple) o seat support subframe (blue) o Tie rods to front wheel (shown separately for clarity) (also purple) on both sides o dashed line is top of triangle. (for added reliability) o slides on red frame to adjust for rider size. o Gets very securely clamped to red frame.
Susex
Here is a another design proposed for a SWB bent with shaft drive: Susex bent
Ice-T trike:
My nephew, Brian has
recently gotten a
recumbent trike - a
"tadpole" (two wheels in
front), the ICE-T"
Trikes make up a
relatively high
proportion of
recumbents. Their
stability and ease of
riding and comfort makes
them very attractive and
they are fun to ride.
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But trikes completely fail my criteria of being able to be carried on fairly standard bike racks. Note: the Ice-T website shows foldable or disassembled ICE-T - see animation on their web site. This would make it more easily transported but I don't think this is practical for the length trips I make. To get some of the stability of a trike, I would be interested in trying something having sprung small ( 8"-12") wheels on outriggers mounted near the seat. Sort of adult training wheels. So far I've gotten skepticism from hpva builders but I continue to think it is worth investigating. It would be helpful if they were foldable to some extent, maybe easily mounted / removed and rideable in a stowed position. I'm currently (3/06) thinking of having the main support for them be the top of the triangle of the seat subframe with a second support near the lower rear of that triangle and pivot along the side of the triangle. Thus pulling them forward would bring them down into use and pivoting them back would raise them and narrow the width. (no sketch currently available) Some recumbents, especially trikes have a full fairing (enclosure) that makes them so much more aerodynamic that they are much easier to propel. The fairing also makes them more suitable for inclement weather. Especially if the outriggers prove practical, I'd consider a full fairing.
The Leitra is a full faired
tadpole trike made in Denmark,
a "velomobile".
Our friend Bruce, shown here
went to Denmark to get his.
He commutes in it here in
Minnesota. His web page:
Leitras in the New World
The front wheels are 90cm apart.
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This page maintained by Fred H. Olson fholson at cohousing.org March, 2006 Fred's Link page