New member

Hello,

I have a 71 750. I've had in for ~20+ years, been stored in various sheds, garages and basements for probably 17 of that. Finally beginning to act on the bug to get it out that's been brewing in me for the last couple years.

Here (hopefully) are some pics.









It'll need a thorough going over, intend to lean on folks here as much as I can for information.

Off the bat, I have a problem with the attachment of the exhaust pipes to the head. It seems that there were once threads of some sort in the exhaust ports in the head into which rings screwed to hold the pipes in. Those threads seem to be gone, or at least compromised, on one side. Is there a fix or do I just need a new head? This head has a broken cooling fin or three anyway. How tough is it to find a head? Should I try to save this one?

Thanks for any input, and if there is interest I'll keep this updated as the resurrection progresses.

Welcome to the forum, looks like a good complete machine for restoration.
On the exhaust port threads - there won't be too many Commandos which haven't had this repair done. If not tightened properly the nut can work loose and rattle the threads away.
You don't say where you are but anywhere there are Commandos there are people skilled in this repair.
There have been a number of discussions on this in earlier posts so a search may come up with a name in your area.
There is always interest in restoration updates so keep the photos coming.

Nice. Looks like Dunstall Decibel mufflers. Hope they are in good shape.

A clearer picture of the head would help, but I think the comments already cover the repair process.

My head has been welded up in this area and a new thread recut. Many Commandos need this, because the head clamps loosen and the thread getts chattered away.
When you repair, and tighten, retigten when the engine is Really hot as tight as you can and you should have no problems.
I have heard of folk boring and bushing, but I have not seen this done.
I would suggest sending it to someone that has done this repair before.
Stu.

bigstu said:

I have heard of folk boring and bushing, but I have not seen this done.
I would suggest sending it to someone that has done this repair before.
Stu.

Click to expand...

Mine was done in this manner. Original threads were cut out, new bushes welded in, and new threads cut. The cost was $243 for both ports, including freight, through my local Norton guy. (He sends the head and his tap to a guy who does the work and sends it back, about a 2-3 week turnaround)

Phil Radford at Fair Spares America does good re-threading work, not sure about broken fin welding...

Welcome.

grandpaul said:

Phil Radford at Fair Spares America does good re-threading work, not sure about broken fin welding.

Click to expand...

Phil repaired a head I sent him a few years ago. He did the exhaust threads and mended a broken fin, (I think he had a donor head). He also welded up a gouge on the mating surface and had it milled. The guy that sold the head to me nearly ruined it. Notorious guy from Chicago.

I saw that CNW does it all. I have a 71 as well . I noticed that yours has a choke lever? Mine has Amal 930 carbs and I didn't see anything in them that would attach as a choke. The lever thing wasn't on it either. It has the ticklers only. Interesting.
What carbs are on yours?