Motorcycle Frame Tubes

[Pete.]

There must be more than a few non-original frames kicking around. When I was an apprentice back in 1987 the company I worked for made 10 copies of an original for a customer. I have no idea what tube they used, being only 17 at the time I wasn't involved in the making of them.

 

[addjunkie]

This sounds good - but could you clarify "2 per side 180* and part. 90 to each tube" please

Now that's a thought - would that tension in the 'spring' add to the frames rigidity?

Every frame Ive ever cut has sprung one way or another.

heres a link to an awful video showing slugged joints and the drilled holes. Basically the above is suggesting drilling each side of the original tube twice, once horizontal, once vertical so you end up with 4 plug welds per side

 

[Shox Dr]

This sounds good - but could you clarify "2 per side 180* and part. 90 to each tube" please

Linky to a thread from 2012. With the very knowledgeable Hotrodder (RIP)

welding a stainless steel pipe to another

Folks I want to have a 316 ss pipe joined to another with as strong a join as I can get. I have access to a very experienced TIG welder but want to ask. I want to socket the lower tube so that the upper tube fits inside for a few inches. The resultant joint is then to be welded, closing the...

www.mig-welding.co.uk

 

[Shox Dr]

Every frame Ive ever cut has sprung one way or another.

heres a link to an awful video showing slugged joints and the drilled holes. Basically the above is suggesting drilling each side of the original tube twice, once horizontal, once vertical so you end up with 4 plug welds per side

My bad. Two hole in each tube

 

[addjunkie]

Every frame Ive ever cut has sprung one way or another.

heres a link to an awful video showing slugged joints and the drilled holes. Basically the above is suggesting drilling each side of the original tube twice, once horizontal, once vertical so you end up with 4 plug welds per side

Whoops forgot the link

https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwjd0Pjr_pyAAxX91wIHHWW2AEMQtwJ6BAgTEAI&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D-yF1GzTY-8Y&usg=AOvVaw2abybIaR_a6GVA9blGEZ8O&opi=89978449

 

[GRW]

Not sure if thus has been said.... but could you not tack weld "stays" around either side of the section to be removed, plus cross braces across to keep it all square before cutting?
You could then do one side at a time to maintain rigidity & alignment?

 

[mangocrazy]

As soon as you cut that frame, it's no longer original and a large part of its value has gone. You would (in my opinion) do far better to sell that frame in its present unmolested state and buy the one you want.

 

[CompoSimmonite]

As soon as you cut that frame, it's no longer original and a large part of its value has gone. You would (in my opinion) do far better to sell that frame in its present unmolested state and buy the one you want.

Strictly, per "letter of the law", as the frame would then be deemed as modified then MSVA test would be due on any bike built on it plus not MOT or VED exempt - not that anybody admits to doing such to a frame

 

[brightspark]

why does it need altering

 

[Franchini]

I cant see an issue with a sleeved joint either. However depending on the age of the pictured frame, not sure it will be ERW. The guys down in wales who was building replicas was using chrome molly T45 tubing If my memory serves me correctly.

What you will find when you cut it to replace the bends itll move all over the shop, so be prepared for it.

If you google Norley frame jig, theres video of the replicas in the frame jig, will give you an idea!

this old video on you tube might help you