NortonMKIIA850 said:Robert Mapplethorpe? Or, something's been clamped and grossly over-tightened to those frame tubes. I've got a kinda sorta supposed to be Norman Hyde oil cooler that clamps in that general area, but you'd have to work so hard with it to produce those marks I can't believe it's that. Something like it though, maybe? Over-tightening crash bar clamps could do that, as I recall back in the 70s and 80s they were both common and quite coarsely made.
gripper said:If, when you slide the front iso bolt in, it goes through without much distortion of the front iso rubber then I think you have not much to worry about. My frame always needed a lot of distortion of the front rubber and after 35 years I found that the the frame was parallelogramed to one side. Probably due to crash damage. All my drain plugs were wire locked and in a previous life the bike had been raced and crashed I'm sure.
rvich said:The the main tube on top straight? In an accident that bends back the front forks, it is likely the top tube will get humped. It doesn't precluded damage to lower tubes from other types of accidents but it is another bit of evidence.
Russ
olympus said:Could if have had a sidecar mounted???
Over jealous tightening of cable ties (zip ties) :lol:
NKN said:
tyborg15 said:It is a USA import.
tyborg15 said:The front ISO fitted but was tight.
tyborg15 said:The frame,engine, swingarm, wheel assembly are currently in being checked by a frame straightener/engineer.
tyborg15 said:I wonder if this creasing will affect the strength of the downtubes as there is more tension than compression forces at this area?
L.A.B. said:No, it's not unusual for Commando spine tubes to curve slightly at that point.
L.A.B. said:If there's any damage to the spine tube it usually occurs in the area just behind the headstock.
ludwig said:If it is just a dent , you could take the opportunity to weld a cross tube at that spot , like is often done .
You can cut the cross tube so that it covers most of the dent . Fill wat remains of the dent with lead .
frankdamp said:Just remember, the original 2LS Italian front brake couldn't develop enough bending moment through the headstock into the frame to cause any structural problems. That's why there was no cross-bracing in the early Commandos. If you slowed down quickly enough to damage the frame, it was because you'd crashed into something!
If you significantly improve the front brake power, make sure you add the cross-brace between the front downtubes and maybe even the secondary top tube.