A Tandem Lowrider From 2 Old Bikes!!
by Prusa Fanatic in Workshop > Metalworking
405 Views, 2 Favorites, 0 Comments
A Tandem Lowrider From 2 Old Bikes!!
It all started when I got a wild idea. I wanted a 'trike' with all 3 wheels in line. Dad was a major help to me by telling me it could be done for multiple reasons (now I have no choice but to prove him wrong🤣). So here it is 2 worthless $2.50 yard sale bikes mashed together to 1 low riding head-turner!!
Supplies
Now it's time to grab you tools & supplies.
Tools you need:
Wrenches SAE &/or Metric
Ratchet & Sockets
Welder, MIG is the easiest to learn but anything should work.
Angle grinder, hacksaw, sawzall etc.
Tape measure
File, wire brush, bench grinder, angle grinder etc. ( to get rid of sharp edges)
All Safety precautions for every tool i.e. welding helmet, gloves, safety glasses etc.
Materials you need:
A piece or 2 or 1/4" metal ( you need to pieces no about 3x5")
Any random pipe, board or anything similar to work as a foot rest
2 bikes ( you only need 3 of the wheels so if 1 is locked up that is fine.)
PS. the 2nd pic. shows all the pieces you will need beyond 1 complete bike.
Preparing the Rear Frame
Sadly I didn't take as many pictures as I should have while building it so.... you may have to sort of build of the pictures. If you look at the pics. You will noticed there is basically 2 frames. The front one is a regular bike and the back is where all the fun comes in.
Grab the worst bike out of the 2 and completely disassemble everything, except the handle bar mechanism. Next cut the front half of the bike of at the set post. Note: The seat post stays with the back half of the bike. Now take the front half of the bike and cut the fork off as close as you can the the bottom bearing on the "steering column" ( I have no clue what this is actually called😉) Grab that 1/4" steel I told you to get and whack off two 3x5" pieces, these will be used to couple the 2 frames together. Figure out the size of you drive wheel axle and cut a a slot out of each piece, in from the long end, so that the axle can slide in. Now all you need to do is take the handle bar of the bike that you chopped up, and we are ready to start building!!
Building the Rear Frame
For pics. look at the ones on the step above.
Grab the front and rear section of frame and run over and flip on your welder!! We are going to weld the Front half of the bike Upside down to the rear part of the bike (which is right side up). The 2 parts will not natural fit together so shave and cut them down till the fit together pretty well the rest we can plug weld (shhh don't tell the pros😉). Get some one gullible enough to believe that welder are safe to hold the pieces in place while you line them up and weld them together. Note: Please make sure that they are straight in line with each other. Now that that is done take front fork we cut off and weld it to where the handle bars mounted. Either orientation of the fork will work but if you make it so that the fork tube runs under the wheel it will look lower (see last pic. in the step above for what I mean by the fork tube running under the wheel.) I hope for your sake your handle bar mount isn't like mine, it is cast aluminum and I couldn't weld it. If yours is like this weld the fork to a steel plate and bolt it to the aluminum mount. Now you frame should look similar to the first pic. in the step above. Now the only thing left to do (who am I kidding) is to weld those 2 little piece of steel with their slots to the rear fork of the rear frame. If you piece is 5" like it is supposed to be you will leave about 2 1/2" over hang the fork (basically put the plate so it will be centered between the frames when joined). The rear frame is complete!!!
Accessorizing the Rear Frame
Now for all the parts we are missing on the rear frame!! You know the pedal crank you pulled off, go grab it. If you pedal crank is like mine it's 1 end will fit nicely down the seat post. If so weld it to you handle bars as straight and as centered as is possible then drop the other end down in the seat post and weld it in will making sure that is is nice and square as well. If you pedal crank doesn't fit in the seat post just cut the one end off and weld it to the handle bar and then attach it however you like to the seat post of the rear frame. Now grab that spare bike seat you have laying around and take all the goodies of it till it looks like the 3rd pic. Take that seat and spread the metal C like clamp open until it fits around the bike bar. Lastly we are going to make the foot rest. Grab that pipe or board you have for a foot rest. If you have a pipe the right size slide it through where the pedals where mounted and weld it on. If it doesn't fit or you have a board or something like that just bolt it some where near there that is comfortable for you. Here again for all these steps just look at the pics. and it will help it make sense.
Final Assembly!!
Alright now for one of the more complicated parts of the build, sorry!! Take the bike we never touched, yes I mean the good one. Loosen up the back wheel till the nuts are almost the entire way off the bolt. Now take the rear frame and push those metal plates with the slots(ant the rest of the frame that is welded to them) and insert it in as far as it will go. This now means that if you tighten up the nuts on the wheel it will tighten both frames together. That is the next step, but while you tighten the nuts pull back on the wheel slightly till the chain is slightly taunt. If the chain is too loose it will slip off while you are riding which can be a bit nasty, so we are going to try and avoid that. If you look at the first pic. you will see the "drive" wheel is off the ground. This common, all you need to do is have a person sit on the front bike and a person sit on the rear frame and it will flex enough to touch on all wheels. Now adjust the seat to a comfortable spot and weld it on or leave it loose so you can slide it for different people's preferences. Put the rear wheel on and your done!! Enjoy your ride!!
If you have a question about any of this or your bike is different than mine leave it in the comments and I will try to get back to you.
Detail? and Future Upgrades?
As far as detail goes... enjoy. I didn't get mine painted yet but that will come.
Future upgrades is the part I am looking forward to. The first thing I am going to do is add brakes to my bike. Yes, with the combination of bikes I had I don't even have pedal brakes on mine yet. Next I need a better kickstand. I've got ideas on how to make it I just haven't yet. Another thing I would love is to make it out of speed bikes; currently mine is hard to pedal and I'd like the different gear options. And I'm working on a way to let the guy on the back help pedal the bike. All this is just ideas and I'm waiting for a good yard sale this year to pick some parts up!!
And the last pic is my bros. enjoying my creation!
Happy Building and I can't wait to see your creations!!