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Riding a recumbent bike is fun, but when your wife can't keep up on her road bike, the going fast fun part of riding a recumbent is greatly reduced. The answer you ask? Get the wife a recumbent of course, I answer. But recumbents are too expensive you say. OK, so you've got me there. Recumbent bicycles, being almost universally hand built, are expensive, generally in the $900 to $2500 range. It's much cheaper to build them.
Parts is Parts
As I had never built a bicycle before, I decided to go with
something (relatively) easy. I obtained plans for the "Tour Easy" a commercially
available long wheelbase recumbent bike, and began collecting parts to build it. The plans
called for two (damaged) 10 speed type road bikes. I was able to pick up an old Raleigh 10
speed at a police auction for $15. It was painted bright green with a brush, but the
abundance of aluminum parts gave away the fact that it was a decent bike. I also donated
my 15 year old Sekai Sprint to the cause. With hacksaw in hand, I dutifully hacked both
bikes apart in the areas outlines by the plans. The parts I kept would create the front
head-tube, the top mainstay tube, the down-tube, the rear triangle, the bottom bracket,
and the front fork. I also needed some 7/8" tubing to create the bottom-stay between
the bottom bracket and the down-tube. As I didn't want to truck on down to the local
hardware store and end up with super heavy wall tubing, I decided to live a little, and
purchased some thin-wall 7/8" steel tubing from "Wicks Aircraft Supply".
They have a large catalog full of parts dedicated to the aircraft builder, such as
aluminum and steel tubing, fiberglass, and other cool stuff. (You can reach them, and
request their free (with an order anyway) catalog at 800-221-9425) The plans called for a
20" front wheel, and I decided that since I wanted the bike to be fairly quick, I'd
order a decent one, rather than scavenging one. I ordered it from "Prairie Designs
HPV Supply". They have a small catalog of parts bent toward the 'bent builder. (You
can reach Prairie Designs at 316-459-6237 or by clicking here to send E-mail.)
The Frame
It helps if you have access to an oxy-acetylene torch. I used a
friend's. A lot of time was spent eyeballing the parts before brazing. It is critical that
the frame be straight, and even move critical that the rear triangle is aligned properly
with the rest of the frame. Even though I thought everything was straight, after I had the
frame all welded together, I noticed it was slightly warped. A certain amount of
"cold" straightening can be done after the welding is completed. I did a little
too much. The frame is straight now, but one of the super thin-wall Raleigh tubes became
slightly wrinkled.
Steerage
The front fork was kind of a trick as well. The plans called for the
original front fork to be bent in order to supply enough rake to make the bike handle
well. Though it was fairly easy to give the fork more rake with a conduit bender, it was
hard to make it symmetrical. The best way to adjust it is to ride the bike, and check if
the bike "pulls" to the left or right. If it pulls, it needs adjusting... The
plans called for the steering assembly to come up and back, and in order to reach it the
steering assembly ended up being a couple feet long, sort of like a boat tiller. Turning
corners felt really weird using the "tiller". As this was to be my wife's bike I
wanted it to be easy to ride. I decided to go the "remote steering" route. This
was a little more complex, as I needed to add a remote head tube, and ball and socket
ended tie rod, but it felt soooo much better. I painted the frame a deep jade metallic
green The auto parts store seems to be a good place to find nice colors for bikes, much
better than at the local hardware store.
Seating
The seat also ended up being complex. There are many commercially
available recumbent bike seats available for around $200. As I'm trying to save money
here, I decided to build one. I've been happy with the feel and performance of my ATP
Vision seat, so I decided to copy it. I built the seat frame from 7/8" chrome moly
tubing. As the Vision (aluminum tube) vision seat had nicely bent tubing, I decided to
attempt to duplicate the bends in the chrome moly tubing. A common method for bending
tubing involves packing the tube with sand, and tightly capping the ends. Ideally this
prevents the tubing from crimping when it is bent. Chrome moly is not nearly so forgiving.
I suppose with the proper heating and tube bending dies, it would have been possible to
put nice bends in the tubes, but I ended up mitering and chamfering the ends to the
correct angles, and the brazing it all together. No muss no fuss. The Vision Seat has a
wonderful mesh seat cover that attaches via velcro. No problem I thought, my wife sews,
and she can just whip one out. Uh, right. A month later I finally got her strapped to the
sewing machine (She won't let me touch it, she thinks I'll use it for performing unnatural
acts of sewing). After a few more weeks, the seat was nicely sewn, but not without
antagonism. A standard sewing machine seems to have problems sewing a multiple layers of
nylon mesh, straps, and velcro.
Coda
Overall the bike turned out nicely, and the sense of accomplishment
and enjoyment that I received building it far outweighed the slings and arrows encounters
in the building process. Not counting the original cost of my 15 year old Sekai donor
bike, the project cost around $350. This breaks down to about $120 for tubing and
hardware, and about $230 for shifters, brake levers, seat fabric, the front wheel, and
other miscellaneous bike parts. I don't have the original plans any more, but I did make
some later, based on the bike I built. Click here for the plans
Side and Frontal views of the bike:
