Random frame question - hollow or solid? - see pic

[650gts]

I'm installing Hugh's CDI system on my bobber and want to mount the regulator on the bottom cross member of the frame. See picture.
Is this hollow or solid? I want to drill and tap so I can bolt it in place. If it's solid I'll look for another place.

 

[WideAWAKE]

You say it’s a bobber?

Looks like a weld on hardtail… those definitely ain’t no Yamaha welds haha

I’d guess it’s hollow. But even if it was solid, why could t you drill and tap it??

Who made the hardtail?? Might get you the answer your lookin for.

 

[gggGary]

Looks like rectangular tubing, I doubt it would be solid. The factory cross member is a round tube with some other shapes welded to it.

 

[Jan_P]

Every designer that is sober would use a hollow section there .
It is because the principle of equal strength sections.
But it is also lighter and simpler to work with in the shop.

If you tap on it with a hammer it might respond with a clang

I would not recommend to drill in a load carrying section like that
May I suggest clamp it with flat bars and bolts through the flat bars instead

 

[650gts]

I just realized how stupid my question was.
It’s part of the hardtail.

It’s voodoo vintage by the way.

 

[Jim]

If that crossmember is solid... it's gonna be a heavy sumbich when it's done.

 

[650gts]

I don’t think it’s solid.