Mavic MA40 vs G40
 

Does anyone remember what years Mavic MA40 and G40 where in production? Velobase is quite loose about them.
Which came first? And what are the differences?

VeloBase - Mavic G40
VeloBase.com - Component: Mavic G 40

VeloBase - Mavic MA40 - red label
VeloBase.com - Component: Mavic MA 40

Found G40 in Mavic Catalog from 1984-1985 (date from cover):

http://i.imgur.com/NDdQD5X.jpg?1

Does anyone have a catalog image for Mavic MA40 - red label?

No sign of them in Mavic catalog 1980:
MAVIC catalog (1980)

Found some more info:

Velo-Retro: Mavic Timeline

After test during 1985, MA40 were shown for the first time at the Salon du Cycle at the end of the year and available soon after.

I bought my first Mondonico in about 1986, it had been built about two years earlier with MA-40 rims. I think they were state of the art at the time, at least for Mavic?

Thanks @Giuanin and welcome to the forum!

What is the recommended spoke tension for Mavic G40? Sometimes vintage rims are rated as being a bit weaker than modern, but G40 are famous for being sturdy clincher rims. G40 is also hard hard-anodized. Is 100–110 kgf resonable spoke tension for rear drive side? Please share if you have Mavic's data on this.

I could not find any info about spoke tension in the Mavic catalog 1984/1985:
The Bicycle Info Projet: Mavic

I am not sure about spoke tension but I’m sure one of the many wheel builders will chime in. I just got a nice set of the G40 wheels built up with Phil hubs . The guy I bought the bike they came on (donor bike) did not know very much about mechanics had let them go without tuning. A few rotations and my spoke wrench and they came right in . Mine have a grey or lighter anodize than my daughter’s MA40 wheels. I tuned both sets of her wheels and they stayed true so I don’t know how the G40’s got out of true. He must have done some rough roads, it wasn’t his weight , he was skinny and only about 5’3” tall. They came with 28c tires and I have 25c tires waiting on them. Both the MA40 and G40 have a good reputation for being strong wheels though. I also have a set of 32h Mavic Open Pro on my Medici that has been ridden a lot and they are very nice wheels.

Dunno, I don't use a tensiometer, but if you have numbers for the Module E2, that should work for G40 too because it's the same rim. The G40 was just dark anodized, some say "hard anodized" and that might even be so, depending on your definition of hard ano. I wore out a pair of G40 rims and I'd say the ano isn't anywhere near as thick as I've seen elsewhere, like Calphalon pans or Zebralight flashlights. I'd call it decorative ano. But I'm no expert on anodizing, just a guy who builds wheels and rides them. Someone here knows more about it no doubt.

But even a decently thick ano layer isn't going to change the spoke tension, right? I mean I'm open to ideas, feel free to clue me in if you know otherwise, but my flabber will be gasted if someone here thinks dark ano rims are actually any stronger/stiffer etc. They might last a little longer if thinning from using the brakes is what kills rims in your usage. For me though, it's more likely to be denting the rim that does it in. Now their ceramic coating on the other hand, that really did extend the lifetime against braking wear, again if you avoid denting them. I'd guess the ceramic coating is maybe ten times more durable than any anodizing I've seen on rims. Still wouldn't change the spoke tension though!

As G40 is to Module E2, so is MA-40 to MA2: same rim, dark anodized.

E2 originally was polished with no ano, but then later they started silver or clear anodizing thhe E2, calling that "Argent". Not all Argent rims say Argent on the label though.
I don't remember ever seeing the MA or MA2 rims unanodized (just polished), I think those got the Argent treatment from the get-go. Anyone remember? They hyped ano as an upgrade, but I think it was cost-saving, cheaper than polishing. Polished rims can start to look bad when the alloy gets oxidation or other corrosion on its surface, but it can be re-polished fairly easily. When anodized rims look bad, there's no polishing that out without removing the ano first, which is kind of a big hairy deal with strong chemicals. And dark-ano rims look HORRIBLE when the brakes start to wear through the dark and show the silver underneath. It's never even, it's all blotchy with worn spots showing up adjacent to each spoke hole. Well everbody here knows what that looks like, I doubt there's any huge fans in the house, fans of half-worn-out dark ano rims. Fashion-conscious types would throw away those wheel when the ano got ugly, or sell them cheap at a swap meet, though they were still fine for riding on.

So for me, I'd pay extra for polished, i.e. gimme a Module E2 over a G40 any day, for a bike that's going to get ridden.

At some point they started using stainless ferrules at the spoke holes, but early E2 rims usually have rusty ferrules when you find them now, with typical outdoor all-weather usage. Even NOS examples depending on how they were stored. Or is that only here in the Pacific Northwet? Anyway the best rims are polished/unanodized, with stainless ferrules. Oops but nobody asked me! There I go again...

I will say, I dearly loved my G40 rims, until I wore them out. I thought they looked awesome — for a while I drank the hard-ano kool-ade at the time. No wait, I just remembered, word on the street was they were "heat treated". I only heard dark rims called heat treated (even though that wasn't true) — nobody used the term anodized at first, in the bike shops I went to or racers I heard from. I don't think Mavic advertized them as heat-treated, but they were slow to get the word out that they weren't. Or to be fair, all rims get some form of treatment involving heat, so you can say they're heat-treated, but the dark ones didn't get a different heat-treatment or "more" heat treating. That was just color.

Mark B

The anodizing is a surface treatment that can be up to .010” thick and very hard depending on the application. It is a hard surface compared to raw alloy. It would definitely keep the wheel from being scratched or dinged easily but also corrosion. As Mark pointed out, that is until the coating wears out. If spec’s as a “hard anodize” it can be quite resilient. The early to mid Trek’s came with the hard anodized Matrix wheels that were almost black and , to me , seemed to have thicker coating. But, in time, the brake wear become visible and some don’t like the effect . I doesn’t bother me any more than the patina that comes with a bike that gets ridden a lot.

Oh wait, Mario Emiliani wrote in Bike Tech Magazine (April 1984) that anodized rims are stiffer! He made some assumptions and cranked some numbers, came up with 21% stiffer than the same rim with no ano. I don't think he measured the stiffness of any actual rim, in anodized and unanodized variants, to confirm that 21% number, so it seems very suspicious to me. Call me unconvinced.

So let's say the G40 may in fact be stiffer then the E2, but so what? That doesn't by itself mean you'd use different spoke tensions, does it? In my understanding, you basically want the highest tension the rim can sustain for the long haul without either buckling or developing cracks. Such thin-wall rims as these, the limiting factor was cracks 9 out of 9 times in my experience — never heard of anyone taco-ing one from over-tension. And ano'd rims do not have a better track record against showing cracks at spoke holes.

In fact, didn't Jobst Brandt actually claim the opposite, that ano was making rims crack? Sorry I don't have a reference to cite, maybe the rec.bikes.tech newsgroup? He said photomicrographs or microphotographs (whatever ya callem) showed numerous cracks in the ano layer (because it's brittle) that could propagate into the metal below. I don't remember the outcome of that argument, but at least some people though ano made rims more likely to crack. If so then maybe the spoke tension should be lower on the G40.

Well I'm not helping to answer this question at all, am I? :o I'll shut up now.

Mark B

https://cimg1.ibsrv.net/gimg/bikefor...56862834c.jpeg
This is from the Spring 1991 Colorado Cyclist catalog.

I once had a MA40 rim crack, cracks around one of the spoke eyelet slowly pulled the eyelet through the rim as a tried to true the wheel. .

Honestly , I think spoke tension and type (butted , non butted or heavy gage) would have a greater effect on that when we are talking about high quality alloy wheels. I have all types of spokes on various bikes and also wheel types and I can't feel any thing different . Out of a dozen or so bikes that I ride with Wienman( conventional and concave) , Araya , Wolber Gentleman Super Champion, Anodized Mavic(3 different types) I haven't felt any weakness or super strength. No failures yet and some of my wheels are close to 50 years old. Just keep them straight and avoid any curb jumping or collisions! Of course my riding is pretty sedate compared to most.:commute:

Thanks for sharing.
Mavic MA 40 and MA 2 shown with the same profile and weight (460 g).

Does it say anything about recommended spoke tension?

Nothing like that mentioned.
I have built maybe a dozen sets of wheels over the years and never used a tension gauge.
When the rim is round and straight- it’s good to go.

As a mechanical engineer, I've spec'ed aluminum anodization on parts hundreds of times. The standard is to use MIL-A-8625, which covers a range of anodization specs.. Type II anodization is often called "clear" anodizing, Type III is usually called "hard" anodization. Clear anodization is a silvery color unless it's colored with dyes, hard anodization is naturally a dark grey color. Anodization is essentially aluminum oxide. Thickness for hard anodization is just a couple of thousands of an inch, it has nothing to do with the strength of the rim. It's significantly harder than aluminum, until you wear through it, of course. I've always wondered if braking on hard anodized rims is less efficient. It's been decades since I rode on them and can't remember. Or maybe in my youth I didn't care so much about stopping or slowing down...

Maybe this? https://yarchive.net/bike/rim_cracking.html :)

Quote:

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The bike industry survives on a thin veneer without much science. That's why
it takes Darwinian time to sort out what's good. There are always new moths
to fly into the flame of the candle of research, as they crash in flames...

---

My experience with building and maintaining G40-rimmed wheels was very good, their shape structure and metallurgy allowed building to relatively high tensions (100+kg) with nary a hint of instability pushing the rim out of true at higher tension levels.
Other narrow rims might begin to show instability at lower tensions.
With 36 spokes, no need to reach for much higher spoke tensions than 100kg imo.

The later MA40 rims did turn up with cracked inner walls too often, but it was always later in the rim's life (the hard-anodization seemed to be a requirement for this malady to turn up).
I do think that their hard-anodizing added structural bending resistance (having straightened many of these period rims using force when needed).

The sidewall anodization of the MA40 was pretty thick and resisted wear for quite a while. It was also extremely slippery when wet if high-performance urethane pads were used (red/salmon pads improved on this, slightly).

Inside width of the E2/G40 rims was under 13mm, while the boxier MA2/MA40 rims were about 1mm wider internally.

The earlier E2/G40 rims better match the classic shape aesthetic of period tubular rims for what that's worth.

I think that the competing Super Champion Gentleman rim offered the best of all worlds, shapely like the G40 and a bit wider like the MA40 (though at a perhaps heavier weight by 10 grams or so?).

Eight year old zombie thread! But then classic rims never go out of style and the added info is great!

So did we ever determine which was the better rim? I have a tendency to collect these rims if they look decent - they build easily (even used, as long as they haven’t been abused) and stay true nearly forever. And they are some of the easiest rims to true. They are nearly bomb proof.

I wish Mavic hadn’t destroyed their 650b dies… They truly made some of the best rims on the planet.

I am not sure which is BEST. I am with you on these wheels as far as quality.The anodize will eventually wear through and some don't like that but it doesn't bother me. I have MA40 , Open4CD , and most recently a nice set of G40 laced too some nice early Phil hubs. I bought a bike just to get the G40's , they are in nice shape with just a little brake wear on the grey sides. He never trued his wheels on the bike(rode it for 15 years) so they were out just a bit , but no "hop" at all . Of course he was very short and thin , I don't think he weighed over 120lbs. I am not a pro wheel guy , it usually takes me several revolutions around the clock to get the wheel in. These trued right up and with very little effort. The whole donor bike was only 125 so I made out. The wheels look right at home on my 1978 Raleigh Pro!

That G40 looks like an early GP4 with horns. I built a pair of GP4s mid '80s and put 17,000 PNW miles on them - completely trouble free. I think I tweaked a spoke or two twice. They died from the rims wearing clear through; that super abrasive lava dust. In places I could have read a newspaper line through the sidewall. (Try that with clincher!)

Building up those GP4s and various GELs as a I swap back to sewups and glue.