A friend of mine was getting rid of her kid's old bike and after already using the handlebars for another project, I decided to make a custom bicycle that would fit an adult rider (ideally all 6'3" of myself) and be aesthetically pleasing in an old school, goofy kind of way. The total cost of the project came out to be very reasonable (less than $100) and could easily have been cheaper if I had more time to look around for salvageable materials.
Also, it should be noted that this was my first foray into bicycle building/upcycling so I made a few mistakes along the way. I was happy to learn from them though and also any advice from more experienced bicycle builders is more than welcomed :)
Step 1: Parts and Pieces and Tools
As I stated in the intro I had an old youth size bicycle just sitting outside gathering dust and rust. It was missing handlebars (taken for another project) and cosmetically pretty beaten up but structurally it was in great shape and more surprisingly the tires, inner tubes and spokes all still looked great. I've looked around and this type of bike would cost around $100 new but there are a plethora of old bicycles out there at thrift shops, police auctions and just sitting in friend's garages that are very cheap or even free, all just waiting for someone to give them some attention.
There were only two expenses for this project, the most costly being the specialty parts to give the bicycle its fun look. All told it cost about $85. Here I listed the 7/8 to 7/8 threaded quill stem, banana seat, sissy bar, and handlebars/grips.
VERY IMPORTANT: Make sure to measure your frame to know what parts will fit! I had a problem with several stems not fitting because I did not measure correctly! What's nice about ordering parts online is that you can read all the dimensions very carefully to figure out what will fit with what, it can be intimidating however so take your time. Many local bicycle stores have miscellaneous parts bins which are great for finding an odd stem (like a 7/8 to 7/78) or other pieces so don't be shy to call around.
This is the other expense which can range from cheap to costly depending on the quality of finish desired. I chose middle of the road Rust-o-leum and the results were ok. If I build another bike I may go for a bit higher quality. You will need a primer, paint and top coat. This cost me about $10 or $15.
There's many great Instructables on bicycle painting, I used this one by Panda Face
To remove the paint I used a wire bristle brush and an abrasive pad, both meant to be attached to a power drill.
I also used a large flat head screwdriver, several wrenches and ratchets, a bike chain tool (not necessary but very, very helpful), and some all purpose grease.
Step 2: Dis-Assembly and Paint Removal
I've never disassembled a bicycle before but it is pretty straight forward (there are official names for everything too which can easily be found on the internet, but I chose to write this Instructable from the perspective of someone who knows nothing about bicycles, which I didn't). I didn't take too many pictures of the dis-assembly but if you need a better idea of how to take a bike apart, the "Re-Assembly" is fairly detailed with pictures.
Removing the wheel bolts enables you to remove the chain (which is where the bike chain tool comes in handy, it simply holds the chain and pushes the pin out with screw), removing the chain enables you to remove the pedals which enables you to remove the main gear, etc. Be sure to keep good track of the pieces that you remove. Bicycles have many small bearings, washers, and bolts which need to be replaced exactly where the came from for successful operation of the bicycle. It may be to your advantage to take reference pictures so you can reassemble everything correctly (plus then you too can make an Instructable).
To remove the paint I simply attached my wire bristle disk and abrasive pad to my power drill and went to town making sure to get into every corner. Since this was a youth size bike it came complete with a lot of decals and thick paint to remove. This is the most time consuming part of the project but once all the paint and rust is off and you see the shiny metal frame it is well worth it, not to mention you will be ready to give your bike a fresh coat of paint.
Step 3: Priming and Painting
From necessity come invention so when I found myself needing a rack to paint my bike frame on I made one from a board, pallet, and extra long, heavy duty drill bit. As the pictures show I placed the board through a snug slat in the pallet then put the drill bit through the board. The bike frame then hung from the drill bit by two small holes near the opening for the rear tire. The front tire fork also fit into the pallet for painting.
Once everything is hanging, it's time to prime and paint. Simply follow the instructions on the can and paint in even paced and distanced strokes.
After a couple coats and a sealer your frame is ready to become a bicycle.
Once again I used the Instructable by Panda Face entitled "Bike Painting Tips" which offered a great amount of insight into bike and metal painting
Step 4: Re-Assembly
Hopefully your bicycle should have relatively similar pieces (Most cheap bikes do in my experience). I laid all of mine out on a board to ensure I didn't forget anything. Be sure to clean off and grease all your bearings and moving parts to ensure a smooth ride later.
The first part back on the bike is the main gear/pedals. Following the pictures a bearing will be placed on one side of the main gear which will be fed through its housing. Another bearing will be placed on the other side and the associated fasteners will be screwed on using a screw driver and wrench.
The front fork will the be attached to the frame with a bearing at the base of the fork stem and another on top, followed once again by the various washers and bolts are associated with steering.
The wheels can go on next. The front wheel is simple, just a pair of washers and bolts. The rear wheel will need the chain on first.
Getting the chain back together is tricky, the impulse for me was to hammer the pin back into the two links to complete the chain but this should be avoided as it will flatten the two ends of the pin. Instead I used my bike chain tool to (after a few tries) push the pin back into place.
Once the chain is on lightly bolt the rear wheel into place with the chain taught (you will have to take the bolts off for the next step anyway and re-attach the seat adjustment lever.
Step 5: Adding the Awesomeness
Now to add the fun pieces to the bike. The banana seat fit nicely with the bike's original seat post which I put at its maximum height. The seat itself secures to the post with a bolt and the post secures to the bike via a small lever.
To add the sissy bar remove the nuts from the rear wheels and pop the rear wheel bolts through the appropriate lower holes of the sissy bar. Now connect the sissy bar to the banana seat by aligning the holes of both parts and inserting the appropriate sized nuts, bolts, and washers.
For the handlebars I chose some high chopper style ones with red grips. To attach the handlebars you will need the appropriate stem and (thanks to the guys at my local Wheel & Sprocket) I was able to find a 7/8 to 7/8 stem which fit perfectly.
The stem (which I believe is called a threaded quill stem) is inserted into the steering column and a single bolt secures it to the fork. To connect the handlebars to the stem, remove the four bolts, insert the handlebars and secure the bolts back.
The handlebar grips fit onto the ends of the handlebars (with some persistence).
Step 6: Final Thoughts
The bike has a very fun and unique look but that comes at a price of ease of use. I won't say it is especially hard to use but it does take some time to get used to. After a couple trips around the neighborhood I felt confident enough to take it into town though and it was a blast to ride. The longest ride I have taken it on is about 3 miles of paved paths
Some possible additions or considerations for future models would be the addition of shocks or a seat spring as the bike is not too comfortable going over medium to large bumps. Also I've been trying to find weight ratings for this model of bike because I'm sure I exceed the recommended capacity (being it is a youth size BMX bike converted into an adult size bike) but the bike has held up well with no signs of wear or damage so far and since it is more of a cruiser it isn't meant to go very fast over rough terrain.
Another addition would be hand brakes or lights for safety. The bike came with coaster brakes which allow the rider to slow the bike down by peddling backwards which is nice.
Hope you liked my first bicycle related Instructable and feel free to vote for me in the Bicycle/Move It Contests!