The beginning... |
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| Using some left overs from some donor bikes, some of the 1 3/4" exhaust pipe used in OK Cruiser top tube and some 1" pipe from my son's swing set (nothing is sacred around here) I mocked up a fat bottom pipe, double top tube concept frame. This will be the first basically from scratch attempt for me as the OK Cruiser was more of a 're-arrangement' build. |
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| The original idea was to use an old 16" front fork,
extend it a bit and use it for a rear chain stay. I ended up cutting up an
old cheap dolly that didn't roll anymore to get some pipe (again nothing
is sacred) which fit tightly over the existing fork tubes After a little
creative angle cuts on the end I forced the pipe over the fork tube and
tacked it in place. The wood stick is NOT where a seat pipe will end
up after all as a custom seat pan will be built.
I didn't realize how much wider the rear hub was than the old 16" front hub and had to open up the spread a bit but it seems like it will work. I used a couple drop outs from a donor and tacked things together. |
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| Working up a basic line for the bottom tube to bend up and match with the double tops. |
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| This is a roughed up rear view (without any alignment, etc.) to get an idea of what it will look like from behind. A seat plate will be made to fit the twin top tubes and a rear seat pan section added. |  |
| Closer view of the double top tube setup looking through where the seat will be. |  |
| The forks finally arrived so here's a rough layout to get an idea of where things will need to line up. Also have a cardboard seat pan stuck on it to get an idea of how that will look. |  |
| There will be two 1" pipes lining up behind the rear seat pan going to the top of the seat as well as merging from the twin top tubes down to the single bottom tube in the final setup. |  |
| Checking the steering tube alignment and how it will line up with the down tube and top tube. I will be cutting the down tube back, inserting the existing steering tube pipe into the down tube for support and then welding things up. Too much rake??? Nah.. never. |  |
| Not a very good pic here but this puts the whole bike in view in one side shot. The bottom bracket will be mounted up on the inside of the down tube to allow my 9 year old son Austin access to the peddles. |  |
| The seat back will likely have an exchangeable panel to allow putting on a back with more padding and spacing allowing Austin to reach the peddles and Z bars from a Stingray. Looks like it's about time to cut that downtube off and give it a try. |  |
Update One - Framed Up |
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| Roughed up frame with seat back and top tubes in place. This is really a scrap build with an old 16" front fork for the basic chain stay, pipe from an old dolly extending it, and scrapped 1" tube from an old swingset for the top tubes, seat back and basic seat post (although there will be no actual post), and 1 3/4" exhaust tube for the down and bottom tube. |  |
| Front shot. I like the attitude the frame displays. I used a short piece of the exhaust tube and squished it to fit the steering tube and squished the other way to meet up with the twin top tubes. |  |
| 3" tire dropped in. We're still looking at options for wheels. |  |
| Rear fits in fine but looks like we'll have to use an idler gear to get the bottom chain run up above the chain stay. |  |
| Simple, straight, and pointy... |  |
| Little better view the current seat bottom. It didn't really turn out like I expected so it might get redone soon. |  |
| Still need to cut the steerer here but you get a better idea of the stance. |  |
| The future rider. We're trying to make sure he can reach the bars and pedals without issues so he can cruise with it. |  |
Update Two - Ride-able |
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| Finished up things for the most part at this time. It's ride-able and running. Rear shot before the rear brake was added. Bad frame design and too fat of a right chain stay resulted in the tensioner need. |  |
| Ready for the first ride with brakes. Quite a pain getting the cable through the tube on this done due to the extra tubing for the existing pipe stuffed inside the down tube and the steering tube inside the bottom tube from the front fork used for the rear chain stay. |  |
| Looking ready to roll... |  |
| ...and we're off. It's a little tricky ride. A little too low, too long and too much rake but it looks wild. We swapped out the 44T sprocket for a 36T to make it a little easier to pedal with the short cranks. |  |
| We have some aluminum pedals ordered, and are still trying to figure out a final wheel combo. Preferred is alloy black spoked wheels but composite six spokes are actually cheaper. Hmm... |  |
| Need to have some shakedown runs to get all the bugs worked out and then we'll tear down, finalize all welds and grind them down, bondo up the joints and paint it some color... still undecided as well. |  |
| Just a few more pics... | |
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 Made a few changes including the Lester wheels and coaster brake drive. |
 I had originally planned on using an old 'Free Coaster' adapter and run gears or a freewheel on the bike but it just seems cleaner with a coaster. |
 The bike seems to sit just about right and is geared about middle run to make it reasonably easy to ride anywhere. |
 Another change is the bars. These provide a little more comfortable position for a kid without leaning too far forward. |
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