CMA Mag Wheels (2019)

[Cheesehead Commando]

Hi All-

Back in the early ‘90s I purchased a project ‘75 MKIII which needed a variety of work, including wheels. At that time, one could still buy new CMA Mag wheels directly from the small company that made them in England. I purchased a set of 18 in three-spoke rims which I believe were 2.5 WM4, but can’t remember exactly. I sold the bike in ‘95.

Last week I was able to buy the bike back from the fellow to whom I sold it. He kept it in a private collection and never even put a mile on it. In fact, I got the title back with the bike and it was still under my name..!

The good news is that the bike didn’t get used. Bad news is that bikes don’t like to sit, so everything will need to be checked;
25 years is a long time to sit, even indoors.

At the time I sold it, I had only put 71 miles on the bike after rebuild, including the CMA wheels.

Does anyone have long term experience with CMA wheels? I am interested in feedback. They are still like new.

I am considering selling the wheels and going back to stock, but thought I would ask this group for feedback.

Thank you!!
Tom

 

[lcrken]

Were the CMA wheels cast in aluminum or magnesium? If aluminum, and stored inside all these years, they should still be as good as they ever were. If magnesium, you might want to have them inspected for cracks before using. But even then, unless they were stored in a corrosive environment, they will probably test out good. I recently put a set of magnesium wheels on my Norton that were over 30 years old, and had been raced quite a bit. I had them tested for cracks by a certified aerospace facility, and they certified them as crack free.

Ken

 

[Cheesehead Commando]

Were the CMA wheels cast in aluminum or magnesium? If aluminum, and stored inside all these years, they should still be as good as they ever were. If magnesium, you might want to have them inspected for cracks before using. But even then, unless they were stored in a corrosive environment, they will probably test out good. I recently put a set of magnesium wheels on my Norton that were over 30 years old, and had been raced quite a bit. I had them tested for cracks by a certified aerospace facility, and they certified them as crack free.

Ken

Thanks for that update, Ken. These are aluminum. They look darn near new, so that part is good, and always stores indoors in semi-heated room (neve below feeezing). My main concern was the fact that CMA wheels were pressed on stock Commando hubs, so wasn’t sure of the long term vitality of that procedure. I’m sure there is more to the construction, but just don’t know much about them. Was hoping someone has been using them long term and would comment on experiences.

Think I may go back to stock anyway and sell these. But am curious anyway.

Thanks again for your comments!

Tom

 

[Blewdy Yaink]

If I'm remembering correctly, CMA wheels are painted (or otherwise finished) very nicely with a very corrosion-resistant finish. The company went out of business about 25 years ago. I know all the reasons for going to 18" wheels, it's just that I think that Commandos don't like them very well (JMO).

 

[baz]

The CMA mag wheels are pretty good quality but very heavy
I assume they are so heavy because the original hub is still inside them and back in the day it was just about the only way to fit mag wheels to a Brit bike, although I did have a pair fitted to a 750 honda F1 but these were not on the Honda hubs and as such had no cush drive!!!
I had a pair on a 750 commando but changed them because of their extra weight
I have a back wheel (conical hub) from a t150 that has been laying outside for 25+ years and it's still not corroded so I'd say they will last forever

 

[Cheesehead Commando]

Interesting..! Thanks for those comments!
Yes, the quality looks really good on mine. Both are 18 inch but look very good on the bike. I’m probably gonna sell them regardless as I want the bike back to stock. Good to know they have solid reviews.

 

[Fast Eddie]

Baz, your comment raised my eyebrows a tad: “the original hub is still inside them”.

Is that correct? How did they do that? How is one secured to the other? Seems a strange way of doing it to me!

 

[Fast Eddie]

Historical note: Mr CMA (I’ve forgot his name) was killed when one of his wheels came out of the lathe and hit him whilst he was working on it...

 

[Bernhard]

Historical note: Mr CMA (I’ve forgot his name) was killed when one of his wheels came out of the lathe and hit him whilst he was working on it...

Oh! I didn't know that. Always dangerous working on machine tools if you don't pay due diligence and take extra care when you machine large components.

 

[baz]

You would send him your hubs and he would machine them down a little
Sometimes you would see the spoke holes or half the spoke holes
Then I believe but (not sure) that he would machine and shrink the bare wheel onto it
He was doing this back in the early 80s and probably in the 70s when it was much less common to have mag wheels
I have a t150 back wheel that's 16" it's not the nicest wheel but what else would you have used back then for a custom mag wheel?

 

[L.A.B.]

 

[trident sam]

I have a set of 3 spoke CMA mags on my T160, the front is 19" rear 18". They are quite rare , I've only ever seen 2 other sets of the same wheels, and one set was on another bike I owned. They look like 3 spoke Dymag wheels but are obviously much heavier.
The 5 spoke CMA mags are much more common for triples, less common for Commandos. From what I remember the guy that made them was killed at the lathe when one shot out.

 

[Bernhard]

Excuse me for asking, but my memory is not as it was, didn't someone make just the drum wheel hubs drums for wire spoked wheels that expanded excessively when the drum brakes were used in anger?

 

[baz]

I have a set of 3 spoke CMA mags on my T160, the front is 19" rear 18". They are quite rare , I've only ever seen 2 other sets of the same wheels, and one set was on another bike I owned. They look like 3 spoke Dymag wheels but are obviously much heavier.
The 5 spoke CMA mags are much more common for triples, less common for Commandos. From what I remember the guy that made them was killed at the lathe when one shot out.

My commando 750 had a 5 spoke on the front and a 6 spoke on the back from memory?
My cb750 had a pair of 5 spokes and I had a pair of 3 spokes that were really quite nice on a Yoshi big bore cb550

 

[trident sam]

Never seen a six spoke one myself. Yep, I really like the 3 spokes on my T160.
My other T160 has Campbray 19" front 18" rear, took me years to find a set.

I'm after a rear 18" Campbray wheel for my Mk.3 if you know of one, I have a good 19"front , but the back has had a major repair and I just don't trust it

 

[Joe Schlaberdowski]

Just two questions: what does CMA stand for actually ( beyond the answer, "a mans name", or whatever, and does "used in anger" imply "used aggressively"? I'm sure I don't have to ask the second part, but I've never heard turn of phrase before. By the way, to all, Merry Christmas! And I finally moved my bike inside to do a few things (like keep the snow off even though it's under a car port. When I was down in Texas, the humid part, I noticed that a soft steel part on a machine I had would rust with no rain at all, if left in the open air, but wouldn't rust if left in an open garage. A car port type roof made the difference.

 

[L.A.B.]

and does "used in anger" imply "used aggressively"?

https://english.stackexchange.com/questions/30939/is-used-in-anger-a-britishism-for-something

 

[trident sam]

Interesting..! Thanks for those comments!
Yes, the quality looks really good on mine. Both are 18 inch but look very good on the bike. I’m probably gonna sell them regardless as I want the bike back to stock. Good to know they have solid reviews.

I'd certainly be interested in them if we could find a way to get them to the UK without it being cost prohibitive.
I have a mint condition standard sized rear Mk. 3 wheel with flanged Akront rim and st. st. spokes to deal with if you should so want.

 

[Seeley920]

Excuse me for asking, but my memory is not as it was, didn't someone make just the drum wheel hubs drums for wire spoked wheels that expanded excessively when the drum brakes were used in anger?

Robinson

 

[Seeley920]

Historical note: Mr CMA (I’ve forgot his name) was killed when one of his wheels came out of the lathe and hit him whilst he was working on it...

John Cerhan

As you worked with Dodgy you should have remembered that, he also made the 8LS front brakes