Building a recumbent bike - part 1As I get more into
e-biking and commuting on my bike, the more I realize how uncomfortable an upright bike is for long trips. Inefficient, too, when compared with
recumbent bikes.
I've been riding to and from work 1 to 3 days per week, 60km per day on a
"commuter-ized" Raleigh mountain bike. I've always been interested in recumbent bikes, so I decided to get one. They're quite expensive, and I've got a friend who is interested in recumbent bikes and knows a lot about welding and building things. So we decided we'd work together to build a couple of recumbent bikes for ourselves.
Initially I wanted to build a "Mach 2" using plans posted on
www.recycledRecumbent.com, but my friend Mike convinced me to go with the
Atomic Zombie Meridian, for several reasons.
Mike wants to build the
Atomic Zombie Marauder, which is a low-racer style of recumbent. He wants it for the pure joy of speed that you can get from the low-racer design. I want mine to be a comfortable, stable, and reliable commuter that I don't mind putting on upwards of 300km per week. I also am willing to sacrifice some of that vaunted recumbent efficiency in the wind for better visibility in traffic, since my commute takes me through fairly busy car traffic. If I like it enough, I may get and install a
WindWrap or
Zzipper fairing to improve aerodynamics and help keep the weather off me in foul-weather riding.
We discussed our plans and designs, collected a few "donor" bikes
for parts, and bought some 1 1/4 inch box steel. Then on a sunny Sunday we started cutting up donor bikes for the parts we needed. Here is a picture of the first cut-up donor bike.
Cutting up the bikes involved using a reciprocating saw and a couple of grinders (one with a
cut-off wheel and another with a grinding wheel). Later we added yet another grinder with a cup-style wire wheel for cleanup work. Of course we made lots of pretty sparks.
Then on another sunny weekend day, we got started on cutting and
shaping the box steel that would form the "spine" of the bike. The three parts are cut to specific lengths and specific angles (according to the design in Mike's copy of the Atomic Zombie book), then welded together. Here, Mike's cutting the main boom to length with the correct angle for the back-rest.
Next, welding the back-rest onto the main boom.
Note the clamped jig that holds everything straight and true while you're working on it. That's why working with box tubing is so nice. It makes it easy to get everything aligned properly. If we were using round tubing, I think we'd still be setting up the jigs to get everything to align and stay in-plane.
With all welds you tack it in place first, verify that everything is
straight and true and proper, then go around it again with the welder, completing the weld. Here's what the completed weld looks like before clean-up.
Next up, clean up the area around the weld with a wire wheel. You
never want to weld or paint on a surface that hasn't been cleaned.
Here Mike is welding a gusset in place behind the seat back-rest. This provides additional
strength.
And here's the start of one of our recumbent bikes! It mostly looks like a big steel hockey
stick right now, but it'll look more like a bike soon.
We measured the angle for the head-set, according to the Atomic Zombie book, but it
didn't look right to us. So we left it tacked in place, so we can easily remove it and change the angle if necessary.
Here's one of the bikes so far, with the headset tacked in place.
Double-checking the seat-back angle on the second bike.
And here's the result so far: two frames for our recumbent bikes! The different lengths are for the different heights of the riders.
Next up, sorting out the headset angle and adding more parts! Woo-hoo! This is exciting.
Cheers,
Grant