Suggest frame mods

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Hi all
Before I get the frame away for bead blasting I'll be having welded on the later side stand support bracket,
Can you suggest any strengthting upgrade mods/gusset plate introduction I should be considering before hand... the frame is on a 72

Thank you
 
The rear rail is best supported with extended gussets at the top shock mount, I add a flat plate on the bottom frame rail where the later side stand knob uses the frame as a stop stop, as you are going to that side stand that will help stop the stand going too far in and stop the frame from wearing.
 
It does have the lower top tube fitted....phew
I can hazard a guess why it was called the "widowmaker"
Unfortunately there is no stamped on frame numbers (that I can see with it painted) or ID plate riveted on

Regards
 
It has been recommended that a cross tube between the forward downtubes is a good modification particularly if the front brake is upgraded.
 
The rear rail is best supported with extended gussets at the top shock mount, I add a flat plate on the bottom frame rail where the later side stand knob uses the frame as a stop stop, as you are going to that side stand that will help stop the stand going too far in and stop the frame from wearing.
I have just checked out these rear gusset plates on "old Brits" so will add these to the ever increasing list
Can yo give me a bit more info (photo?) of this plate which stops the side stand as the stop??
 
Pad to protect frame from sidestand and stop the side stand going back to far.

Suggest frame mods
 
Hi all
Before I get the frame away for bead blasting I'll be having welded on the later side stand support bracket,
Can you suggest any strengthening upgrade mods/gusset plate introduction I should be considering before hand... the frame is on a 72
Thank you

You might want to consider simply buying a 1971-1974 style frame. At least then, the frame would be correct for the paperwork. I assume that your engine numbers match the paperwork? How about the numbers stamped into the top of the transmission case? Maybe you have a 1969 or 1970 with a Combat engine installed?
 
This is the sort of front cross tube piece mentioned above by rvich. The rear shock mounts on this frame are also modified for a little more support for the rear loop, but mostly to move the mounts a but further apart for this particular build.

Suggest frame mods


Ken
 
You might want to consider simply buying a 1971-1974 style frame. At least then, the frame would be correct for the paperwork. I assume that your engine numbers match the paperwork? How about the numbers stamped into the top of the transmission case? Maybe you have a 1969 or 1970 with a Combat engine installed?
Engine & tranny number do match and are correct for the year..
 
Olympus, how far do you want to go on this build? There are people here who have added tie rod links between the frame and cradle and all sorts of stuff that are all good to get done when the frame is bare, if at all. The following link has some very cool ideas in it.

https://www.accessnorton.com/NortonCommando/race-commando-handling-secrets-revealed.8641/

The links (rose joints) don't get discussed much these days. I know there have been some other mods more similar to the Doug MacRae as above that have been successful. This is not a bad time to think about this kind of stuff.

https://www.accessnorton.com/NortonCommando/to-link-or-not.8326/#post-109341

https://www.accessnorton.com/NortonCommando/extra-isloastics.5227/page-2#post-55455
 
Olympus, how far do you want to go on this build? There are people here who have added tie rod links between the frame and cradle and all sorts of stuff that are all good to get done when the frame is bare, if at all. The following link has some very cool ideas in it.

https://www.accessnorton.com/NortonCommando/race-commando-handling-secrets-revealed.8641/

The links (rose joints) don't get discussed much these days. I know there have been some other mods more similar to the Doug MacRae as above that have been successful. This is not a bad time to think about this kind of stuff.

https://www.accessnorton.com/NortonCommando/to-link-or-not.8326/#post-109341

https://www.accessnorton.com/NortonCommando/extra-isloastics.5227/page-2#post-55455
Many thanks rvich. its like opening a can of worms for sure.
I will fit the lower front tube cross brace & side stand support
Cut off the old side stand bracket as is restricts fitting the lower engine bolt
Leave the original rear cross brace in place to give extra rigidity, but cut off the stand support brackets
Fit the rear top rail strengthening gusset plates
Another question.... on the above frame photo from Icrken, i see that he has fitted a front down tube horizontal brace.... cant see this on AN pages??? is this a home made mod do you know???
 
Many thanks rvich. its like opening a can of worms for sure.
I will fit the lower front tube cross brace & side stand support
Cut off the old side stand bracket as is restricts fitting the lower engine bolt
Leave the original rear cross brace in place to give extra rigidity, but cut off the stand support brackets
Fit the rear top rail strengthening gusset plates
Another question.... on the above frame photo from Icrken, i see that he has fitted a front down tube horizontal brace.... cant see this on AN pages??? is this a home made mod do you know???

It's just a tube I cut to fit and welded in. It was a pretty common mod for racing Commandos back in the '70s and '80s. I did it on both my Commando framed race bikes back then.

Ken
 
On my frame I added and extra mk3 type isolastic under the gearbox and another in place of the head steady,
I converted the gearbox cradle to take a mk3 swing arm pin with the cotter pins,
And I over braced and under braced the swing arm with steel pressings,
 
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