bending the frame rear loop

Your frame is bent from having both exhaust pipes on the same side. When you crack open the throttle all the thrust is on the left!

a walk in the park, I did it on my T140. Stout lever (I had 2" x 1/4" wall square tubing laying around, 6' long) and an Ancra tie down strap back as far as you can get it. Pad with old leather gloves and have several motobud's hold the bike. Go easy, it bends easy. Check, adjust as needed.

Just adding my 2 dollars worth here, the rear loop maybe bent on it’s own, or the whole chassis maybe bent.
Have you checked the wheel alignment with a straight edge :?:
Also the headstock is vertical :?:

A straightedge will not necessarily tell you if the wheels are in line. The rear wheel can be cocked and the front turned only slightly and it can look like it is straight but it is not.

batrider said:

A straightedge will not necessarily tell you if the wheels are in line. The rear wheel can be cocked and the front turned only slightly and it can look like it is straight but it is not.

Click to expand...

OK, then a basic check can reveal other problems, but a frame jig is the only way to check that nothing else is bent.

DogT said:

Had the bike out today for a run and got back, started fretting about that darn rear loop. I already tried bending the tangs on the seat that go under the rosettes, so I figured I can bend the metal without the powder coat flaking off. I bent the dickens out of the seat tangs to get them to line up. So, here's how I proceeded, hobot style.

6 lb. maul, 2x4 blocked from front of frame loop to garage door frame, greasy rag over the place I'm going to whack, and place 2x4 over the rag and give it about 6-8 well placed whacks with the maul. Did it in stages to see if it was working or messing up. First few didn't seem to do much, but as I got to about 8 it seemed to start to move and appeared right. Put the guard back on, and it seems to line up pretty good. I think there is something strange about the guard though, even though it lines up with the frame center tube, there is still a bit of bend. It's visible in real live more than in the picture which looks pretty good.

Anyhow, I thought all youse guys would like this one.

Dog

Click to expand...

Good job, Dad would be proud! (the whole BFH thing) Just another tip.. when I've had to adjust things with paint or chrome, electrical tape as a first layer right on the paint, then some additional padding. Keeps the slight abrasions from happening. Just .02

I should have checked the frame when I had it apart, but I didn't. Pretty much didn't know how. I notice now that it's together that the cradle is real close to the frame brace that goes by the sump drain. So close that I couldn't fit one of Jim Comstock's sump valves. Also after I put on the Hemmings adjusters and removed the boots, I can see that none of the isolastic end collars and mount collars (20 and 25 here http://www.oldbritts.com/1971_g9.html) line up very good. But I don't know if that's due to a bent frame or just basic sagging because I don't have the engine spring like the MKIII, I can put a floor jack under the engine and then they line up much better. Knowing what I do now, I would have at least checked the measurements on the isolastic areas. Otherwise it doesn't seem to exhibit any riding problems that I can tell, I've never had the tank slapping issue and it rides pretty much like advertized.

Heck, now that I've got my anodized slides, I can even take my hand off the throttle at a stop and it doesn't die.

I suppose I could check the headstock vertical-ness close enough with a bubble level on each wheel?

I could have put a few pieces of innertube over where I was whacking on it too, but the greasy rag and 2x4 seem to have done the trick, didn't mess up the coating.

My other thought was to strap the bike into the front end loader on the tractor and pull the loop with a come-along from a tree. If I could figure out how to keep the bike fixed to something, the hydraulics on the tractor loader would make it real easy, but a long lever would probably be safer.

At any rate, it's apparent that the powder coat will not flake off and it's not that hard to move.

Dave
69S