1974 Commando - correct tires/wheels/spokes

Have a question about the wheels/tires/spokes on my 1974 Commando. The tires on both front and rear are Dunlop K81 4.10 x 19.

The front wheel is marked as follows - WM2-19 Trade Dunlop Mark Made in England - and has nipple and spoke diameters of ~ 0.295" and 0.145" respectively. Rim width (measured to the outermost edges) is 2.69".

The rear wheel is marked as follows - WM 2.19 Jones 91 0033 Made in England - and has nipple and spoke diameters of ~ 0.245" and 0.125" respectively. Rim width is 2.40".

Interested to hear any facts, comments or hearsay on what the correct wheel set-up would be fore and aft, and whether any part of what I have is right or wrong. Thank you.

Here is a post from L.A.B which gives information on the markings.
I thought Triumphs and BSA's had Jones rims (and Dunlop rims,combined sometimes )

MC274 would be a disc brake front on a non Mk111 ?

mkiii-rims-markings-t14026.html

Also:
dunlop-mc286-rim-t11324.html

L.A.B. said:

Also:
dunlop-mc286-rim-t11324.html

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That is the rim you mentioned before (iirc)
Same as the MB41 but bigger nipple holes.
That was the rim I needed but could not find,I ended up getting Buchanan spokes and nipples to suit the MB41.
That later rim would mean matching nipple OD's front and rear.
Maybe the late Mk2a got that rim.

I'm pretty sure a WM2 rim actual width is 1.85", measured from where the tyre bead sits in the rim. Although WM2 rims are what Norton fitted you'd have to check with the tyre manufacturer as to what rim widths the tyres are designed for. E.g Avon recommend 2.5" width rim for the 100/90 19 roadrider. Actual fitted max width of tyre is approx 109mm which is approx 4.3". A comparable dimension to the Dunlop but the rim is significantly wider.

WZ507 said:

Have a question about the wheels/tires/spokes on my 1974 Commando. The tires on both front and rear are Dunlop K81 4.10 x 19.

The front wheel is marked as follows - WM2-19 Trade Dunlop Mark Made in England - and has nipple and spoke diameters of ~ 0.295" and 0.145" respectively. Rim width (measured to the outermost edges) is 2.69".

The rear wheel is marked as follows - WM 2.19 Jones 91 0033 Made in England - and has nipple and spoke diameters of ~ 0.245" and 0.125" respectively. Rim width is 2.40".

Interested to hear any facts, comments or hearsay on what the correct wheel set-up would be fore and aft, and whether any part of what I have is right or wrong. Thank you.

Click to expand...

Thank you all for the helpful responses. The links cited provided great additional info. However, I am still trying to answer the original question, i.e., "Could the current wheel/spoke combos on my 1974 Commando be the correct items supplied on the bike as delivered?"

I looked a little more carefully at the front rim and now see the MC 275 inscription, and since the manual suggests 9 gauge spokes and since I have 9 gauge spokes, the front wheel seems correct.

The rear wheel is the one I have questions about. Has anyone ever seen a WM 2.19 Jones rim on a 1974 (or any other year) Commando? I also looked again at the spokes and they are in fact a butted 8/10 gauge spoke (~ 0.160" dia/0.125" dia). So this is also consistent with the manual specification that calls for this 8/10 butted spoke. So everything seem right, but the thing I am questioning is the Jones rim. What say you about a Jones rim?

Nortons fitted Dunlop rims, to fit those Dunlop K81 tyres.
So it sounds like someone has had a Jones rim laced onto it, for whatever reason.

I'd comment that back in the 70s when I repaired/restored a 73 850, the back rim had a patch of rust on it.
Rather than obtain a new rim, I just simply obtained a whole rear wheel/brake/sprocket/axles, and fitted that.
Heavier duty spokes and all, cost less and fitted right up no problems. Better chrome too.

If your Jones rim fits and looks good, why change it...

I just checked my MK2A, built Nov 73 but 74 model year, spokes are 0.161" full length and nipples are 0.25", as I have owned the bike since 1984 I am 95% sure the wheel is the oiginal one, but cannot see the MC number as in this wet climate I oil the rim and dust covers the rim (but no rust) .

WZ507 said:

The rear wheel is the one I have questions about. Has anyone ever seen a WM 2.19 Jones rim on a 1974 (or any other year) Commando? I also looked again at the spokes and they are in fact a butted 8/10 gauge spoke (~ 0.160" dia/0.125" dia). So this is also consistent with the manual specification that calls for this 8/10 butted spoke. So everything seem right, but the thing I am questioning is the Jones rim. What say you about a Jones rim?

Click to expand...

http://www.ebay.co.uk/itm/Norton-Comman ... 0919348962

commando-wheel-rims-t2684.html

another-wheel-question-t14798.html#p178410

Oh, one other thing: seems to me most later era Commandos had a Jones on one end and a
Dunlop on the other.

Click to expand...

L.A.B. said:

WZ507 said:

The rear wheel is the one I have questions about. Has anyone ever seen a WM 2.19 Jones rim on a 1974 (or any other year) Commando? I also looked again at the spokes and they are in fact a butted 8/10 gauge spoke (~ 0.160" dia/0.125" dia). So this is also consistent with the manual specification that calls for this 8/10 butted spoke. So everything seem right, but the thing I am questioning is the Jones rim. What say you about a Jones rim?

Click to expand...

http://www.ebay.co.uk/itm/Norton-Commando-Rear-Wheel-Jones-Rim-No-tyre-/360919348962

http://www.accessnorton.com/commando-wheel-rims-t2684.html

http://www.accessnorton.com/another-wheel-question-t14798.html#p178410

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Being a dumb Yank, I had never heard of Jones rims and wrongly thought they were some odd duck or cheap outcast rim. But prompted by L.A.B.'s searching results I did some more digging and found that Jones rims were a highly regarded rim, were an equivalent of Dunlop, and were a standard staple on Triumphs and BSAs in the early 70's.

I found the following on the Brit Bike "British Motorcycles in General" Forum -

Not to worry. My '71 Daytona came brand new with a Dunlop front rim and a Jones rear. Apparently they were interchangeable depending on what was closest in the parts bin as the bike passed down the assembly line.

Click to expand...

In light of the above and LABs finding -

Oh, one other thing: seems to me most later era Commandos had a Jones on one end and a
Dunlop on the other.

Click to expand...

it certainly seems plausible that the rims on my bike could be factory correct (build date on my frame tag is 6/74). I suspect supply and demand was no different in 1974 than it is now, i.e., when something was in short supply you were at times forced to source an equivalent item elsewhere (Jones instead of Dunlop). So perhaps at some time late in Norton production, wheel inventory varied, and the bikes did have a Dunlop on one end and a Jones on the other. If Triumph and BSA employed Jones rims, it doesn't seem like much of a stretch to think they could find their way into the Norton factory also.

Whereas I was initially sure the Jones rim was wrong, the body of evidence building suggests that it is in fact very possibly correct. Until proven otherwise I'll assume the Jones rim is correct. Thank you all for digging into this.

I wouldn't be too terribly surprised if Norton used Jones rims as an alternate supplier. It is a little surprising though that your rim is laced with butted spokes. I own a 1974 Norton Commando with its build date of 6/74 and its equipped with a Dunlop MC286 rim, .300 inch diameter nipples and non-butted 9ga (.144 inch) spokes. The Mark II/IIA parts supplement book only refers to one part number for spokes and nipples. However, I have found errors in the parts book and also during 1974 Norton continually made changes that are not reflected in the parts book. So what you have may very well be original.

Also you noted in an earlier post that the front wheel is laced with 9 ga spokes. Actually it should be laced with both 9 and 8 ga spokes. The 8 ga spokes are used on the right hand side.

PeterJoe said:

It is a little surprising though that your rim is laced with butted spokes. I own a 1974 Norton Commando with its build date of 6/74 and its equipped with a Dunlop MC286 rim, .300 inch diameter nipples and non-butted 9ga (.144 inch) spokes. The Mark II/IIA parts supplement book only refers to one part number for spokes and nipples.

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My Mk2/2A supplement lists three different spokes.
065729 Spoke [20]
065727 Spoke, Inner L.H., [10]
065728 Spoke, Inner R.H., [10]
063207 Nipple, [40] (known to be: 9G x 0.300".)

PeterJoe said:

However, I have found errors in the parts book and also during 1974 Norton continually made changes that are not reflected in the parts book. So what you have may very well be original.

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Your 6/74 Commando's rear wheel specification of: 9G spokes, 9G x 0.300" nipples and MC286 rim seems consistent with the parts supplement information, however I think early MkII/IIA models could have had the previous 8/10G butted spoke rear wheel assembly (as listed in the factory manual), with 10G x 0.250" 021693 nipples and Dunlop MB41, or in this instance, possibly a Jones rim.

PeterJoe said:

Also you noted in an earlier post that the front wheel is laced with 9 ga spokes. Actually it should be laced with both 9 and 8 ga spokes. The 8 ga spokes are used on the right hand side.

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And you are correct sir. I just measured the right hand side of the wheel, and it does indeed have straight 8 ga spokes. Evidently my powers of observation are not what/where they should be. Thank you for pointing this out.

I also have a fairly stock 74 850, registered in May. The front wheel I know has been replaced, but the rear is Jones.