Tall Bike project - up and running!

So steering tube is the big question, if you are being fancy you extend the fork tube and weld the front of the frames together with a single top an bottom head bearing, So the fork tube and the frame joint at the front has to be parallel. All a bit fancy pants for a hack toy.
For true bodging people weld the base of the top bikes forks to the handlebars of the bottom forks.
So we are going the middle way which is to leave both sets of bearings in place and join the cut down top forks to the bottom forks and worry about strengthening the frame up later:

Top forks chopped



Cleaned up and holes drilled out



Bit of thick wall tube wedged in and shown the sparky glue gun




Being able to spin the handlebars round while grinding made me very happy !

Tube to join up:




Trial for length





Next stage is to align the frames and get the length of the front steering tube sorted out.

James (&boy)

Bit of chopping to get them sitting a bit better:






Might be easier to add some gussets to get strength here.

James

This looks way more fun than a trampoline as your ticket to A&E! Love it

So the thought with the top of the top to bottom bike fork tube extender is to drill 4 holes and chamfer the top of the pipe to give 'spot' and full round weld attachment. This pipe is pretty thick wall (gas pipe ?) and must be close to 3mm wall thickness so very solid. So that's the top sorted out.



This then gives a fixed end to measure and cut down (red on image) to meet up with the top of the bottom fork extension piece. The thought here is to drill 4 holes (blue) and then cut slots down to these (orange). As the top of the bottom fork extension piece is longer we should have a bit of adjustment to tack the frames together at the back and then go up or down a touch at this bottom attachment point to get it all nicely aligned before welding through the slots to stick everything together.

It will be very interesting to see how solid this all ends up. It might be quite funky to not add an additional tube to join the front of the frames as without metal hole cutting stuff in the workshop getting an extra tube to fit might take longer than everything done so far. Will suck it and see.

James (&boy)

grizz, yep seen both of these and they are on the list, we will get some more scrap bikes at some point.
Swing bike might be easier to ride though!
James

Cool project jamesd1972 ! When I was in art college I built a back-pedal bike as part of a project. It looks (I still have it!) like an ordinary bike because it has a chain case, but it's surprisingly tiring to ride. Also, starting at the lights is a bit difficult at first because it's so counter-intuitive to pedal backwards to get moving. It's a bit like driving an automatic for the first time: at some point you'll inevitably hit the brake pedal with your left foot with all your might when your intuition tells you to shift gears.

So a quick session with the sparkly glue gun has yielded some obvious progress.


old seat tube had chrome removed and was shoved in the top of the bottom bike to reinforce things.











long seat tube didn’t want to fit down far enough so was polished up and moves in and out a bit better will lube the bottom a bit and satin black the top some point soon




 

Action shots now mandatory apparently 







 We could do with some chopper handlebars I think 













Wire ran out so need to return to finish welds etc but looks good so far.

James & boy

This is top level stupid.
Man club approved.