Nstillwell,I hope you will try your best to determine whether the steering head is twisted;if that is,it will require more work than a beginner can do.
I watched a talented amateur measure my CB350(which was bent at the steering head)and he started by taking the bare frame and setting it up on some large wooden blocks on a level surface(his shop floor),then shimming along the bottom until the frame sat straight-up and level.He placed a couple different thin levels along the top of the rear portion(from the airbox/battery area,on back)of the frame to determine whether it was level:not leaning to one side or the other but sitting dead-level.
There are certain spots along the rear of these frames which are factory designed and meant to place a level across.
He then placed a Large/long threaded rod with large washers through the middle of the steering head,and at that point we were able to see the way the steering head was bent.
I left him to his work of straightening it at that point.
Wow! It is crazy what someone can do that knows what they are doing! This does sound like it is way outside of my abilities… I do want to pull the engine out and see what it looks like. Maybe if I can get a long pipe or a threaded rod of some sort, I can measure from the centerline axis of the steering tube to the swing arm pivot and get an idea of what I’m working with.
I wish they had the info that you are talking about available to the public. It would be nice to know where to set levels and how to place them to check a frame. But I’m sure the guys that do that have learned through a lot of trial and error. That knowledge would be awesome to have!
The good thing is you've decided to keep the bike and repair/replace the frame problem
Why not start by putting the bike on the centerstand on a known,level floor.,then completely remove the seat,rear fender and fuel tank,then take a top view picture of the frame section under the seat and I should be able to point out where the frame level spots are on the top frame rails.They will both be across from each other at the same place,where you can lay a thin level across the top of the frame from left to right(the same orientation as the axles)and then shim your centerstand with cedar shingles,etc. until the bike sits level.
I would at least remove the headlight completely so you can get a better view of the seam in the frame
or better yet remove the complete front-end with the engine still bolted in and place a stable,large wooden block under the front of it to hold-up the front wheel of the bike just enough to remove the front-end and install a long(4'+),thick threaded rod into your steering head and stand back and look at it:keep checking the levels and take many looks/views.
This is NOT
a precision way to determine if your frame is bent, but you may see it if it is twisted.. depending on your perspective..
I hope someone else can mention a way to properly measure the frame,at this point...
I can't say it enough,keep the level on top of the rear frame rails during this entire process and keep checking to be sure your bike stays level for an accurate view of the steering head.
