Topic: Goldwing front end on CB750, Top triple tree

[azuredesign]

For the past several months, Ive been trying to find a workable top tree for my front end conversion.
I wanted to lose the bar mounts, using clip ons above the tree as I was aware that the fork tubes would extend above the tree. Because they are hollow, grinding off the mounts would leave holes in the casting, weakening it. I was not concerned about changing the angulation or offset of the forks, as I had no idea of how that would affect handling. I did want to have a couple of threaded holes to attach an aluminum mounting plate to hold a tach and speedo.

 Ive thought about having a top tree or set of trees made, I spoke to several folks about doing so including Rob(Voxonda), who is informative, and a pleasure to communicate with, but did not have anything in hand. On a ride out to watch the motorcycle cannonball run commence in colorful Newburgh NY, I had the great fortune to meet with a machinist from NH who suggested that I simply weld the holes once the bar mounts were removed. I gave him the top tree, and these are the photos he sent me yesterday. Apparently the tree was tigged by a friend of his who has an aviation fbo.

[70CB750]

That looks good!

[754]

 Nothing wrong with that, hope it slides on easily. If it doesn't weld it while clamped on the tubes with lower tree.

[azuredesign]

Nothing wrong with that, hope it slides on easily. If it doesn't weld it while clamped on the tubes with lower tree.

Thanks, that's a good point as I don't know how it was set up during welding. One would hope that it was clamped to maintain the relationship between the mounting spots for the stem and both legs. We'll see!

[anders288]

754 you don't know that your talking about it's cast aluminum not steel or  iron alloy .

I have been welding on aluminum race bike engines and frames for over thirty years.

And it just happens that my buddy that welded it is a certified airframe welder.

[azuredesign]

 

Now we know, thanks Anders! I did some reading following seeing your post. Is the reason that one doesnt have to worry about distortion of material as much with cast aluminum because it dissipates heat so easily?

[754]

 Actually it may be Forged aluminum. If you don't see any distortion caused by welding, fine keep thinking like that...

[754]

 I am not saying it did warp, rather it could. It it were to be done repeatedly, I think a fixture, is a good idea..

[anders288]

The part is cast

[754]

 I like to think the Honda Motor Co is wise enough to not use cast parts. For things like triple trees..

[anders288]

Honda Motor Company is and was wise and it still cast