British Standard

Status
Not open for further replies.

Jackman

VIP MEMBER
Joined
Jun 30, 2016
Messages
242
Country flag
Are all Norton Commandos British Standard? Where do you guys by your British Standard sockets and wrenches?
 
no offense to the traditionalists but having had 6 Commandos since 1970 I have never had the need to purchase whitworth or BS tools, making do with a normal wide assortment of SAE and some Metric you can pretty much find a socket or wrench to fit on anything on a Commando, yeah ok maybe not perfect fit but they turn the damn things just fine
 
Jackman said:
Are all Norton Commandos British Standard? Where do you guys by your British Standard sockets and wrenches?
As I understand, all Nortons have British Standard in various locations, but not all fasteners on a Norton are BS (you know what I mean...); some are Whitworth, some are SAE (as far as the wrenches are concerned). I buy mine on-line from any number of supply houses. The Gunson Whitworth combo set has worked very well for me, and it comes in a very nice leather roll-up case.

Nathan
 
1up3down said:
no offense to the traditionalists but having had 6 Commandos since 1970 I have never had the need to purchase whitworth or BS tools, making do with a normal wide assortment of SAE and some Metric you can pretty much find a socket or wrench to fit on anything on a Commando, yeah ok maybe not perfect fit but they turn the damn things just fine

I use to use what I had but now I have a full set of whitworth sockets and openend/ring spanners just for my Norton, its a bit ruff tapping the wrong size spanners on whitworth bolts to undo them, you can not go wrong with the right fitting tools, once you got them you have them forever, a lot better than butchering nuts and bolts anyday, makes the job a lot easier as well and they aren't that expensive.

Ashley
 
I bought a set of 6 WW wremches and 6 WW sockets 30 years ago from the local Norton shop. But, I go ot most of mine from my father in law who was a retired machine repairman for Holeproof. He had two or three good sized toolboxes out of which I got a very large set 1/2" WW and another large set of BS/WW wrenches.

Commandos also have CEI and BA threads...

fastener-sizes-part-number-chart-t17435.html
 
Jackman said:
Are all Norton Commandos British Standard?

Almost all the CYCLE PARTS on a Commando use american fasteners -= UNF. (used to be called NF or SAE)
So american wrenches are made for them and will fit perfectly.

The engine and gearbox are a different matter, they are mostly BS cycle thread,
and a bit of everything else thrown in, as mentioned above.

If you see the interlinked circles symbol on the nuts on a Commando, it means its UNF.
And this is not being rude....
 
Jackman said:
Are all Norton Commandos British Standard? Where do you guys by your British Standard sockets and wrenches?


Depends on what year the Commando is…. There was a transition period where this bike had almost every screw thread going :shock: ....except bastard :!: :(
 
When the Commando was first built, the British motor industry was converting to the American Unified system. So the vast majority of cycle parts are UNF/UNC. The engine & gearbox on the other hand, were only supposed to be a stop gap fitment until a more modern engine could be prepared. As we all know, this never happened & hence the continued use of Imperial thread forms i.e BSW/BSF/BSc for engine & gearbox. Electrical items use BA thread forms.
So, in order to work on a Commando you require a set of BSW/BSF , a set of A/F , & a few BA spanners & sockets. Also some A/F allen keys.

Martyn.
 
Bernhard said:
Jackman said:
Are all Norton Commandos British Standard? Where do you guys by your British Standard sockets and wrenches?


Depends on what year the Commando is…. There was a transition period where this bike had almost every screw thread going

The Commando had a considerable quantity of *Unified* threads from the beginning, and although some BS threads were later changed to Unified the actual number was relatively small, so there's not all that much difference between early and late model Commandos.

*http://www.ring-plug-thread-gages.com/ti-N-vs-UN.htm
The “UN” thread form was developed after World War II by representatives of Great Britain, Canada, and the United States of America, to prevent recurrence of the wartime difficulties in supplying fasteners and tools in both British Standard Whitworth and US Standard configurations when and where needed. In 1949, after years of committee meetings between Canada, England and United States of America the American National Standard Series was replaced with the Unified Inch Standard Series. In the end there were three base reasons identified for the change. The first reason was to provide interchangeability with Canada and United Kingdom. The second reason was to allow for interchangeability in the growing global marketplace. The third reason was to correct certain thread production difficulties. The jointly-developed thread form was named the Unified Thread Form. the Unified Thread is also referred to in the B1.1-2003 as Unified Inch Screw Thread. This Unified Inch Screw Thread both superseded the previous British, Canadian and American national standards, and later served as a prototype multi-national thread form standard that was eventually metricified to become the ISO Metric Screw Thread (the M-series).
 
On my '74, the majority of fasteners are fractional inch (SAE) sizes. The 7/16, 1/2 and 9/16 inch abound, with an occasional 5/8" and 3/4". There are Whitworth bolts on the engine, particularly the head bolts, which are 1/4 Whit. A 14 mm wrench is close, but a bit loose. That #2 nut in the back of the head really needs a 1/4 Whit box wrench, ground for a bit for clearance. Then there are a few 3/16 Whit (gearbox shifter) that's just a tad too big for a 7/16.

So, a 1/4W and 3/16W open end box and a 1/4W thin walled 3/8 drive socket are IMO required tools.
 
Most of what I found on my 71 Commando takes US sized fractional wrenches. My BSA A10 is not, but I have an old set of Snap-On sockets that has 7/32, 9/32 and 11/32 sized sockets and these seem to be a pretty close fit to most of the whitworth fasteners on it.
 
MikeG said:
Most of what I found on my 71 Commando takes US sized fractional wrenches. My BSA A10 is not, but I have an old set of Snap-On sockets that has 7/32, 9/32 and 11/32 sized sockets and these seem to be a pretty close fit to most of the whitworth fasteners on it.

I'd be curious about any of those sizes on a Commando ?

I just bought an 11/32 UNF ring spanner, and its tiny !!
Its very close in size for 1/8 W - Enfield rocker gear has this miniscule size.
I'm not aware of anything on a Commando that small (something in the points housing maybe ?).

You'd need things a fair bit bigger to do any Commando engine work.
 
Dang. Thanks LAB.
I'll get that around the right way one of these days.
The spanner itself is just marked 11/32
And is quite small...
 
That's just shy of 3/8" - I think I've used that on the hex studs supporting the points cover.
 
maylar said:
That's just shy of 3/8" - I think I've used that on the hex studs supporting the points cover.

An 11/32" AF (0.344") spanner on the points pillar studs (2BA hex. 0.324") is extremely loose and slips.

9/32" AF fits the (7/32" x 40 ME thread) Amal carb top cable adjusters, and a 5/16" (although slightly loose) fits the lock nuts.

1/4" AF fits the points wire and condenser stud nuts.

http://classicmechanic.blogspot.co.uk/2 ... chart.html
 
Bear in mind that the wrench sizes for Whitworth aren't the actual nut size, but are based on the bolt diameter. As I recall, the early "nut across-flats" size was 1.25 x the bolt diameter +0.25". As stronger steel alloys strted to be used, the a/f size formula changed to 1.125 x bolt diameter +0.125". I don't remember if BSF wrench sizes were based on the same formula as Whitworth. I think they're actual across-flats sizes.
 
Status
Not open for further replies.
Back
Top