Build a kid's long-wheelbase low racer recumbent bicycle

This is a companion piece to my other instructable on building a low racer recumbent. My oldest kid likes to ride bikes, too, and had to have a racer to match mine. It was a much easier build and I'm very pleased with the results.

Step 1 Materials and Tools

Materials:

• One whole kid's BMX-style bike with 16" wheels
• The steering tube and steering components from another bike (or some ingenuity)
• One length of 1" EMT electrical conduit (around $7 for 10')
• One length of 3/4" EMT electrical conduit (around $5 for 10')
• A couple of feet of 1" x 3/32" mild steel or some other stout steel for brackets
• Enough 1/2" - 3/4" plywood to fit your kid's back and posterior
• Miscellaneous nuts, bolts and screws
• Optional: An old 3-speed bike for the rear hub, front sprocket, and chain guard

Tools:

• Flux core welder, welding gloves, tip dip, wire brush, chipping hammer
• Various clamps
• Angle grinder with cutoff/grit/wire wheels
• Bench grinder with cutoff/grit/wire wheels
• Hack saw
• Bike assembly tools
• Woodworking tools (to cut out and shape the seat)
• Files/rasps

You will also need a positive attitude, patience, creative thinking. If you have a child helping, please use common sense and pay extra attention to safety. Explain what you intend to do, why it is unsafe and what you are doing to make it safer. Make this a fun learning experience, not a trip to the hospital.

Comments

[davec8656]

hey Homba, love the build. I'm getting stuff together to build one and was wondering if any major differences using a 20" kids bike instead of 16". I have parts of a 20" left from my first build.

[MACKattacksnipe]

for the steering i would have just cut the frame and re welded it so alls you need is a longer peace of pipe

[rlnbkseeberger]

This has inspired me to at least try to build a recumbent unicycle. Now that would look cool cruising down the street.

[japanbiker]

Bellisima!

[idiosyncrazy]

 Thanks much for sharing this and your other plans.  Both look great.  I'll be using your plans as inspiration to build my first recumbent.  Thanks again.

[sayoian99]

can you mass produce those?PWWEEEESE?

[homba]

I wish I could - not enough used bikes for raw materials laying around. If you can get a hold of a bike and borrow/beg a welder, you should try a build - this is not a difficult project. There's only 5 welds or so on the frame and 4 welds for the seat brackets. Everything else can be done with simple hand tools (hacksaw, files, etc) and a drill. A grinder and wire wheel attachment would help, but is only a time-saver.

[sayoian99]

is it possible w/o welds,and on a budget?

[homba]

Budget - definitely ... scrounge bikes from the trash, EMT tubing is well under $10, and a can of primer and a can of paint is cheap. The most expensive items would be the tie rod ends and a die to cut threads (but you could probably just buy threaded rod cheap) No Welder - maybe ... you might be able to do some clever bolting, but it won't be very strong and might be dangerous. A welder can be pricey unless you're clever and a little risky and build one of the frightening 'ible welders. I would get everything cut out, cleaned up, and ready to weld and see if you can nicely ask your local school or trade college if the students could weld it for you. I've had some success with that in the past. Pizza and a couple of 2-liters of soda are usually appreciated. Do you have an uncle or brother-in-law or a co-worker that you can beg to weld it? Offer to scrounge an cut out a frame for him/her if they will do the welding. I've done that before to get access to a tool I couldn't afford. If you give it a lot of thought, I bet you can come up with a solution. My uncle has tons of tools (he used to own an auto-repair shop), so I would often bring over lunch to get access to a tool I needed. He'd often get interested and help out, too. If you put it out there, you might even find someone on the site that lives close that would be kind enough to help out. You can do it! Just get into that creatively-cheap-a$$ mindset and come up with a solution to your lack of resources - trash picking, thrift store-ing, scrounging, and bartering are great skills to develop and have :)

[sayoian99]

well,what frame materials do i need,i think one of my neighbors(lots of tools with him,you should see his garage...)has a welding tool(im not 100% sure...) that i might be able to get help with...

[homba]

You need EMT from the local hardware store (Lowe's, Home Depot, etc.). It is metal electrical conduit and the cheap bike builder's friend. They are almost always galvanized (zinc coated). Please make sure that you sand/wire wheel/chemically remove the coating 2 inches or so away from where you will be welding. Also weld outdoors and use a fan to blow the fumes away from you (blow it across the work in front of you). Burnt zinc fumes will give you metal sickness which isn't deadly, but it's really unpleasant and long-term not too good for you. There is and 'ible somewhere that shows how to remove it with drain cleaner or toilet cleaner (can't remember the details, so you might want to look it up). I always sand the ends with emery paper until you get to the shiny metal underneath. If you can find a copy of "Atomic Zombie's Bike Builder's Bonanza" from your local library, it's definitely worth a read. The author (Brad Graham) is on the site and has posted a couple 'ibles as well. I didn't end up building any of his designs, but they are a good starting point if you haven't done anything like this before.

[sayoian99]

well,the idea for my bike that im making is more like the one shown http://www.instructables.com/id/Front_Wheel_Drive_Center_Steer_Semi_Recumbent_Bicy/

[homba]

I've seen that one - I say go for it. Front wheel drive is odd at first, but you get used to it quick. Good Luck!

[sayoian99]

do you know where i can get a 20" bike for about $10-$20?(for front wheel drive.)

[homba]

I always either do thrift store or trash pick ... if you put it out there to neighbors and relatives that you are looking for free junk bikes, that will often work. You might not get exactly the bike you are looking for, but I bet you'll end up with more old bikes than you can use (I've had that happen in years past). At this point, I find mostly 80's era 10 speed road bikes, crappy walmart/target "Magna" brand pieces of junk, 16" kid's bikes, and 20" bmx bikes. I use the 10 speeds if they are good quality, strip the magnas for parts if they are any good, use the 16" and 20" for stuff for my kids and recycle what's left over. Having said that, it's been around 2 years since I've done any bike building. My kids are growing out of what we currently have, so next spring may be the time to start up again.

[ininlolo]

i loved it thats cool

[sayoian99]

would a 20" bike work,too?

[homba]

It should - you'll probably want to bump your tubing up to the next size (or measure the bike frame tubes and match them).

[traceuis]

I guess I missed the step where you explain the steering mechanism. Could you give me some detailed information on it? I have a couple of donor bikes and I'm currently learning welding, MIG, TIG and 70/13 as well as fabrication. Thanks

[homba]

It's pretty basic - add another steering tube and handlebars in reach of the driver. Attach tie rod ends to tabs the same distance apart from the pivot point of each steering tube. cut and thread a piece of round metal stock to connect the tie rods. If you have any more specific questions, feel free to ask. You may also want to check out my other recumbent instructable. It uses the same steering set up.

[SirJoey]

Homba, I really like the looks of this bent. I'm considering building this one with 24 or 26 inch wheels, as an adult's bike. Any thoughts? Thanx! :)

[homba]

Yes - do it! ... and post photos! ;)

Check out my other 'bent instructable for an adult version. Recumbents are great if you want to go fast and want comfort. If you can scrounge free bikes and have access to a welder, you can make a fantastic bike for super-cheap!

[SirJoey]

(removed by author or community request)

[homba]

You're all set, then! I would say this is an easier build than my other one, though. Also, you don't have to fool with chain management either. I wasn't terribly happy with the steering on this one. I ended up putting in a stop as the wheel could flip around backwards. It wouldn't do it while riding, but it freaked my kid out.

[Rockerx]

Well I have the parts...finally. but I decided I'm going to build something a bit different. I was planning a bike but after seeing what I had on hand i settled with a trike design. so anyway heres my sort of concept video of my project.

Just thought you'd like to see it. i'll let you know when I get it done!

[blackflashdog]

good concept!! thats exactly my idea also but settled on a 4 wheeler that is almost complete. see pic.
' how do i upload a picture?

[Rockerx]

Thanks! For the pic just hit add images and click upload from my computer...or something like that. I'd like to see it.

[homba]

Front or rear wheel drive? Front would be easier to build - check out http://www.python-lowracer.de/ for ideas. There are several people that have made trikes in this style and they work well. Here's my version:

[corey_caffeine]

is that yours?

[corey_caffeine]

looks pretty nice i've always been turned away from that design how well does it steer?

[homba]

The center steer stuff is really squirrely - it took me several hours to learn to ride. There are severl trike versions that are pretty nice - you can keep your hands free while you bike!

[corey_caffeine]

i think i might do a rear wheel steering tadpole trike so i dont have to do the crazy pulley stuff

[Rockerx]

Front, I was thinking I could take one bike and cut off the handlebars and front wheel. Then flipping that upside down so that I could use the bottom bar (old top bar) to weld on the pipe to extend to the back steering and seat. I like yours in the video. It has a pivot in the front for turning right?

[bedbugg2]

thats sick!

[dpocius]

Very cool! Reminds me of a bike project I saw in a Popular-something when I was a kid, back in the '60s. Same basic idea, except it used a near-horizontal steering shaft with a universal joint at the top of the fork and a homemade airplane-style steering yoke. I think I still have a copy (before Xerox!) of the scaled plans somewhere. Now I'm inspired to dig it out and build one after 40-odd years!

[homba]

It's not this, is it? I remember what you are talking about, but I haven't seen it in a while. My dad used to pick up lots of back issues when I was a kid ... I'd really like to know why my mail isn't delivered by rocket, though. It seemed like such a good idea at the time ...

[bob.smitty]

Not as good as the 20 hour week, the helicopter replacing the car and the self cleaning house... the future isn't what it used to be. *sigh*

[dpocius]

No, the one I'm thinking about was a construction article from the '60s. It was a recumbent with the front wheel forward of the pedals. Your butt was only a few inches from the ground. The U-joint was a modified half-inch drive socket wrench part. I'll try to find the article, tho it may take a few months, the way things are going right now.

[The Wapusk]

I think you're remembering Robert Q. Riley's "Ground Hugger". There is also a link to a modern version from there made of composite materials. I've ordered both sets of plans over the years with the intent to build before I discovered Atomic Zombie's designs. Now I'm half way though my build. Though the curved "retro" lines of the Ground Hugger are attractive, I found them to be intimidating for my first project.

[dpocius]

Yup, that's the one! Good to see it's still around. I too was intrigued by the elegant lines of the design.