Topic: Can someone please help me with CB750k3 frame tube diameter?

[swoardrider]

I just purchased a set of Tarozzi rear sets and they mount by clipping onto 2 frame tubes.  Unfortunately the guy I bought the bike from shaved the rear passenger foot peg section off of the frame.  Can someone please tell me the diameter and wall thickness of the tubing the red arrow is pointing to in the pic?  I want to buy some tubing and weld about 4" back onto the frame to mount the rear sets.

Thank You
 - Grady -

[70CB750]

It measured at 22 OD.  Sorry wont cut it to get you thickness

[Geeto67]

At this point don't bother.

By the way, you have to weld the whole triangle back in place to get the strength.

If I were you I would just weld some plate steel to the frame, put the tarozzi mounts on the shelf, and just bolt the rear set through the plate steel. Tarozzi controls are singe bolt through style so all you need is one hole to mount them.

[swoardrider]

It measured at 22 OD.  Sorry wont cut it to get you thickness

Thanks, so much!

[lucky]

The tubing is 1/16 thickness. .063 thousandths.

TiG weld if possible and keep the heat down.
This is 40 year old metal. You will be welding over
 the HAZ which is already degraded.


Make sure the metal is clean shiny metal only
 SAND....  Do NOT use a grinder!!!

Do not  fully weld in a triangle.
Just 3 one inch long welds and weld both sides.
You can MIG weld with a 110V MIG welder.
It will create just a little more heat on the frame.

[swoardrider]

The tubing is 1/16 thickness. .063 thousandths.

TiG weld if possible and keep the heat down.
This is 40 year old metal. You will be welding over
 the HAZ which is already degraded.


Make sure the metal is clean shiny metal only
 SAND....  Do NOT use a grinder!!!

Do not  fully weld in a triangle.
Just 3 one inch long welds and weld both sides.
You can MIG weld with a 110V MIG welder.
It will create just a little more heat on the frame.

Thanks Lucky,
My neighbor will be welding it, and after 5 minutes of looking at it, he said the same things you did, Tig, sand, keep heat minimal, etc.  So its reassuring to know that my neighbor is on his game! 

[lucky]

I am a certified welder and a certified welding inspector through the American Welding Society.
I spent most of my life welding tubular structures, including stainless and chromoly aircraft engine mounts.

It sounds like you did find the right person to help you.