I wanted to get my nephew a tag along style bike as he struggles to cover the distances we cycle. A lack of cash and a garage full of dead bike frames and parts made me think about building one. I started to think about what i had and started to get the bits together. I had an old steel ladies frame and a cut up kids bike and a 20" rear wheel from various other projects. After more rumaging i found some old handlebars and a stem too. Im no expert welder but i have a gasless migwelder and find it foolproof ( i may live to regret that statement one day).
First job was respacing the rear of the frame for the single speed wheel. I first measured the frame width then took of this the width of the wheel then divided this by 2 which was the distance each side of the frame had to be moved. I used a 6 foot length of 2 by 2 to tweak the frame using the seat tube against the rear stays one side at a time. It is best to go a little bit at a time until you have reached the correct size then turn the frame over to do the other side to the size of the wheel. This method insures that the frame stays symetrical.
Next I cut the rear stays by the seat tube and bent them so they were at the same level as the cross bar. The paint in the relevent areas was ground of with an angle grinder mounted wire brush. The stays were then rewelded. The saddle tube was then cut with a hacksaw down to a suitable height for a six year old. I hacksawed two slots at the back of the seat tube about 3mm apart and broke the middle out with a pair of needlenose pliers to alow for the seat clamp to operate.
I cut up an old handlebar stem at the end of the tube which goes into the forks and filed it to the contour of the cross bar then tacked it in place. When happy that it was in the right position, it was fully welded.
I decided the down tube of the kids bike would make a good front tube. I cut this down the centre of the fork tube with a hacksaw and opened it slightly, using the anvil on the back of my vice, until it fitted over the fork tube of the ladies frame. The paint was removed from the relevant areas then the tubes welded together. Its starting to looklike a real one now!!
I now turned my attention to the hitch. I took the top bit of the seat tube (cut off the top of the ladies frame) and welded on some 3mm stock i had lying around bent into a u shape with a gap big enough to allow a 25mm square tube to fit between. an 8mm hole was drilled through these and another in the 25mm square tube 75mm centres but perpendicular to give side to side as well as up and down movement (like a universal joint). At the end of the kids bike top tube some 8mm holes were drilled to complete the hitch which I then beefed up with some washers welded in position. In the photos i have actually put the hitch on the bike upside down!
As my nephew is into transformers especially bumblebee, my wife suggested painting the tow along yellow. As well as a can of yellow smoothrite I also bought some autobot stickers to finish it off. I got hold of a flag to make the tow along more visable when riding in trafic. This is the first and last time I paint a frame with a brush! It looks ok in the picture but not to good up close but I can justify this as it is for occasional use and he will be having far to much fun to care (hopefully). Hours of fun await. Hope you like it Kana.