Tall Bike project - up and running!

[jamesd1972]

So as a way of avoiding the obvious stuff we should be sorting on the Land Rover, House and Garden we stumbled on 'Tall Bikes'.  Essentially you weld one old frame on top of another for the shitz and giggles.
As we have some scrap bikes kicking around as part of something else and a welder this was obviously a great idea. As is the modern way for research you have to head off to youtube, this one is pretty charming:



Anyway to business :

We have bikes
A crappy ladies mountain bike and a crappy gents mountain bike with a bent / split frame - Perfect !

[jamesd1972]

Frame on base bike is pretty bent:


Slightly better after being jumped on:





Split ground out by the boy:





Hopefully once welded it will pull in a bit more. I think we will also shove an old seat post down there to strengthen the area up as this is where the other frame goes on.

[jamesd1972]

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 !

[jamesd1972]

Next up is the bottom forks:
These also needed extending ready for a joining piece:

Holes drilled and again piece of tube that may or may not have started life as a door frame into concrete support.

[jamesd1972]

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)

[jamesd1972]

Forgot to mention that drilling one of the holes in the bottom bikes forks resulted in a resounding whack round the side of the head from the forks because the vice wasn't quite tight enough and they pivoted round. Not knocked out but sure did hurt and made a nice clang - curse word sound by all accounts. Boy had the grace to not laugh immediately which was better for his survival.
James

[jamesd1972]

Bit of chopping to get them sitting a bit better:






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

James

[bstardchild]

Enjoying this - thanks for sharing

[generallee]

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

[jamesd1972]

Apr 26, 2023 10:39:30 GMT generallee said:

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

Definitely women and children first ! Not that much further up than a big horse, but I may defer riding it to those with quicker healing bones... 
James

[jamesd1972]

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]

Yup….

Love it, have ridden a few weird bikes.

Here are a couple to get you to the next level of fun.

They are addictive.

SWING BIKE





And for the real pro….


BACKWARDS BIKE

[jamesd1972]

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

[sasquar]

ive got a half built reverse steer bike in the corner of the workshop, at some point ill finish it.... tall bikes look waaaaay more usable and fun though!!

[melle]

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.

[jamesd1972]

A little more progress, chopped and sliced the steering tube.










Toby has also been doing some training with a friend on a TIG and we used this to hot glue the extended seat tube together. Thought here was that the bike on top was relatively small and this was a way to help. Two mild steel tubes joined together with a big threaded rod (m14 I think) through the middle, so seat higher and also more tube down in the frame.
Worked it as nut - seat tube - nut - seat tube - nut.










Not yet finished but very solid, and we can mess with peoples heads by leaving the joint in the middle showing which might look like a weak point but isn't.

James & boy.

[jamesd1972]

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

[winchman]

Your mad I think its great!
I made a reverse steer bike, once the novelty ran out I gave it to the local Scouts they made a fortune using it for fund raising ride the bike 20ft get £20 £1 a go no one managed it!

[crockpot]

This is top level stupid.
Man club approved.

[jamesd1972]

So we have rootled in the bike bits and found some fancy NOS brakes for the back, these should keep themselves out of the way 



 
and some front cantilever brakes

swapped out the stem and handlebars - found out the existing stem was dangerously overextended.




















also found some old school chrome sturmey archer brake leavers.
not sure about the bar ends. We shall see, but much like for the new stem and bars
James & boy