Head Tube Extension

[Michael Gordon]

I'm using a set of Long Shen lugs, and I'd like to extend the head tube above the top of the lug.

The closest piece of tubing I can find for this is a piece of 4130 tubing, 1.375" OD with either a 1.245 ID (too small) or 1.259 ID (too big). The 1.375" OD is also bigger than the diameter of the head lug.

Unfortunately, I do not have a lathe.

Does anyone have any suggestions on what I can use for this extension, or is the 1.375" OD x 1.245" ID the best bet, and I just need to work it (lathe preferred).

Thanks!

[Michael Gordon]

Here is a picture of what I want to do. I looking for help with the ideal piece of tubing for the extension.

Moustache Cycles, this picture came from your site. Thank you!

HT Ext.jpg

[Eric Estlund]

This is rhetorical, so bear with me.

ID:
-What is the OD of your HT?
-What sort of gap do you need for a slip fit with appropriate brazing gap?

OD:
-What is the approximate OF of the lug you are trying to match?

As you suspect, precision can be achieved faster with a lathe, but you can do a lot to change the inner and outer dimensions of tube stock. Using the two measurement parameters above you can get a ball park idea if the over/ under sizes you need and best match the tube diameter and wall thickness based on your need and ability to manipulate the material.