found drill hole in frame

FUDGE . I ere on the side of paranoia . But in this case , as there were 30.000 STOCK Commandos , Id kick it in the guts .
Take the chain saw to it . ( as it were ) NOW , some are skilled with hacksaws , some are skilled with disc grinders .

If you can cut EXACT fits , you tack it together with chewing gum , super glue , or something . Then get a skilled tradesman
( WITH a ticket or thousands of hours at it ) ( Most Shop floor guys ! ) to TACK - then Sequential weld youre creation athwart .



A 3 or 4 inch tube . Something Vauguely in that vernacular . AS YOU CAN SEE , the top tubes no longer a ball cruncher .
The theory is Get the SEAT low . ( so maybe shorter shocks - if the need replacing . or laydown . You want 110 Lb springs anyway )

You get the seat , put the driver in it . Put the engine in front of him . The wheels there , and use chalk . Then turn the chalk into tube while the drivers at the pub .


You use a piece of string to keep it straight . This should be good enough to win a world championship or two .

Actually , you pick up a bleedy great piece of channel or i beam . STRAIGHT . from a scrap pile . And make a big L dead in plane at 90 deg . Seq. Weld .

THIS ONES copied from a 75 Commando F 750 .So theres a bit of leeway . But a big tube to the FRONT bit on your rear subframe , with 45 deg. gussets at front to head stock / steering head tube .
THAT will likely want refinishing . But if you pressed steel discs ( on with a 1/2 hole in it for drift ) in where the races seat , it might keep them true . Whip along 1 inch one side , then imediately the other.
Or your keel will be bowed .
Its pretyy basic kids stuff mechano , one step past .


Go awn , be a devil ! use the CRADLE & cetra . Throw a big stiff tube in the guts ( with a third iso below ) New Tunnel in a dinged tank & you can knock the dents out true .
Night Classes woulda doneit once . The 2 1/4 STOOCK top tubes often BOWED . So FIRST ORDER OF ATTACK is , get a STRAIGHT EDGE , and check if its STRAIGHT .
Commando frames are pretty soft , Look at the top of the front down tubes for ripples . LATE sup frame SHOCK mount plates , the INNER goes aft more to stop the loop falling off.
overloaded touring . the Side Stand Bracket can twist the frame there . Though I think yours maybe pretty straight . A lot wernt run into theground , there .
Quite a few ran into something , in Aus. Was told ' weve doone plenty ' . ( buy at auction , take off the tank , pull the front end out , put the tank back on , flog off at 300 % profit . )

AnywaY . GET THE FRAME BARE . Measured centers of cross pieces , a piece of white cotton though & about , and you soon see if its kaput . But a ' custom chop ' isnt as scary
as youd think , done step by step . aranged logically .

Some people have to be awkward . https://motorshedcafe.com.au/egli-project-part-iii/ waste of a Trident . Same with a Rickman . the Frames are MADE for TWINS . Pre Units .

s orrta like this , maybe . ( were all A M C eventually . always thought the COMMANDO frame was derived from THIS . ( Like the Suzuki T 250 / T 350 Frame ! )



Its partly its heritage / ancestry . So its all pretty elementry , Best of the Lot . Whats a Commando Anyway ! . they used to do roof chops & channeling with Gas torches .
Which is why you used to have moulded chopper frames . BOG to cover the birdshit welding ! But as weldings common exactitudes no longer an impossability , theres
not a lot stopping you . You did want a PROJECT ! ? >

If you just patch welding the drill holes - might pay to put say a 1/4 hole in the plate across the rear . spray in fish oil or zinc paint , whatever .

You sometimes get untreated welding repairs , on cars , rotting out . As they start rusting if unpainted . Could throw some in before welding them .
Stand on end to weld , Then slosh it around after its done .

Theres a note somewhere , a guy replacing a rear subframe ? on the tube type / material spec.

https://andover-norton.co.uk/en/shop-drawing/457/early-commando-frame-repair-items
the 064282 are the reifrced inner shock / subframe brace , while your at it , ad the extra .

Butchering it with a big top tube , you could end it at the rear side uppers , And throw in new front subframe rails LEVEL , to there .

Matt Spencer said:

Was just my warped humour re J P S frame , you see the top tubes are transposed .

Though , WHILE YOUR AT IT , Id throw a ISO under the transmision .

Let us know if the holes Top & Bottom of the Top tube . And a shot of the muffler , inboard rear ? .

Click to expand...

Rightiho .

BS.980 - CDSI . refered to as subframe material in F 750 ' Thruxton ' data sheet .

One would think that #!*% etc . Tho SOME frames were Italian , unpainted - rusted . ( ditto ) .

A say 1 1/2 in ( across ) x 3 in long PATCH tack welded over the ole's . Say 3/4 or 1 in welds , ditto gaps .
Patch clamped or hose clamped , rolled 16 G compatable material ( Furniture Tube ! its NOT sealess )

would be as good as any . Or a plug or two . Youd find differant craftsmen would have familiarity with
what they considered preferable . IF it were say a 1/8 steel dropped in , welded , dressed curved .
you could thread for a schraeder valve , under . If it went Phftt ( the air didnt stay in ) thered be a crack / pin hole or something .
A old race trick was to blow up gas tanks . As in Plug & inflate to expand ( volume ) . which was banned after they twigged ( for P R ) .

So 100 P S I might be overdoing it . A David Brown Brass Radiator Id been going to test o 20 PSI .
At bot 13 it went ' PHFIT ' and blew all the verdigriss off , increasing its volume by a pint or two .
Fitted good in the 51 Fordson truck / van grill . Excellently . So try wot yer find .

Or go at it , full bore . If your inclined . Steel rods across through the ISO mounts etc , secured to a ' table '
( a old scrap pair of steel things from something rather ridgid ) would hold THEM straight .
THAT ( 36 inch rods thru ) is a good way to sight & measure frame dimensional accuracy .
Stand off & eyeball theyre parrallel ( from F or R ) and measure twixt for the other plane .
or chop a stick and try at ends both sides .For mega check . Equal nip = equal distance .

So Fred Flintstone tecnology is still applicable .

MUFFLERS . Thanks for posting the picture . They DEFINATELY look like the GOOD Wassell 60s/ 70s ones .
the rolleds rear lip . The Centers however look Dunstall or Pirate Dunstall .with the groups of tubes center .
Theyre a similar ' mount ' bracket ON the muffler body . The Long / large area - alows several stich welds , so the loads dispersed .
Also the thick cone materials disinclined to crack . ( Std. thin Commando mufflers were often self dismantling )
IDEA trip is a Triangular Bracked , with say a 3 inch lower space so TWO BOLTS secure the 1/8 steel ( custom ) bracket to the mount
on the muffler . Therefore the third , top , bolt is positioned definatively in relation to the muffler . So if its all done aligned it STAYS
aligned .

A decent exhaust shop , IF there weldings magnificent , could handle the frame .



Anti Stick sprayed on to stop splatter sticking . But SPLATTER was for Hondas etc and Bird Sh*t welding , of the early era .
THEY DIDNT EVEN CLEAN THE SPLATTER OFF . Wereas of course British Motorcyles were built by skilled tradesmen . Tho
sobriety declined with younger trainees .

THOSe are Reasonable Beads . You see the lowers width varies . Tho both are acceptable . Ragged Unevens NOT .
so look at some samples / examples of the guys work . Phot them even , to study at lesure . THEN decide .
Some old retired welder'd probly take it of for the pleasure of doing it . So the guys ATTITUDE is important too .
Not CASUAL , unless he's got a million hours up .