Topic: 71 CB750 and 75 cb550f upper tree

[Industrial Cafe]

are they interchangeable?

71 750



75 cb550



they look about the same from stem to fork and leg to leg, the gauge mounts look the same.
but there's a hump in the 550 around the stem.
maybe it's the same as the hill on the 750....

[754]

That polushed one looks like 73 -76 750.
 500 fits as far as I know, that flat area under the stem nut may require a shim, make sure nut is tensioned against the tree.

[Industrial Cafe]

yeah I think you're right.
  but it was on my 71 and I can't remember the exact year bike I got it from.

[ttr400]

The offset is not the same.

So far this is the measurements that I have:

CB750K 69-76 = 60mm
CB750F ?       =  50mm
CB750K 77-78 =  50mm (not comfirmed)
CB550 K ?      =  45mm (not sure of year but it was a K model)
CB350F 72-74 = 60mm
CB400F 75-77 = 60mm

Fork spacing on the 750 trees I have measured are 182mm. I have only measured one 550K and that is also 182mm. the 350/400F are 172mm.

Kevin

[Industrial Cafe]

you're right on the 77-78k, I have an upper tree off a 77 and it's 50mm offset.
77 CB750k tree-



hmm, what about the 550F?

[Industrial Cafe]

anybody have a 550f, a straight edge, and a tape measure?
I can figure out inches to MM if you don't have it.

[754]

Sorry for steering you wrong.. pun intended..

 The 550 has less offset, I checked one yesterday, i aplogize for the mistake..




 now if a 550 has the same offset as a 77/78 750, then you can swap the 550 tree to get lower bars on the 750!

[Industrial Cafe]

cool, thanks everyone!

[Zaipai]

Wow its like reading a foreign language.. What is the offset and how would I measure it? If anyone wants to take on that "howto"..

[Industrial Cafe]

from the center of the stem nut to the center of the fork nut.
it measures out to 2.362 inches (60mm)
I'll mock up a 73-76 tree and take a picture.

[Industrial Cafe]