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Discussion Starter · #1 ·
Some of you won't want this, but the weight weenie 29'ers will. Here is basic specs, 29 mm tall and 20 mm wide and 390 grams and if you can read the picture you can see what it is made out of.

Sorry about the blurry pics but this a sneak peak.
 

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Ligero said:
Some of you won't want this, but the weight weenie 29'ers will. Here is basic specs, 29 mm tall and 20 mm wide and 390 grams and if you can read the picture you can see what it is made out of.

Sorry about the blurry pics but this a sneak peak.
Is 20mm the inside or outside width?
 

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Recovering couch patato
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I'm guessing 20mm outside, for such a tall and light rim?
Nice road rim ;-)

I'd be interested to hear what the advantage is that mag holds over al in such an application, is it much stronger?
Also I wonder if the height is just there for aerodynamics, or vertical stiffness. Most road rims are way narrow, but wouldn't a wider, lower rim of the same weight be stiffer?
 

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Cloxxki said:
I'm guessing 20mm outside, for such a tall and light rim?
Nice road rim ;-)

I'd be interested to hear what the advantage is that mag holds over al in such an application, is it much stronger?
Also I wonder if the height is just there for aerodynamics, or vertical stiffness. Most road rims are way narrow, but wouldn't a wider, lower rim of the same weight be stiffer?
Magnesium is not as strong and more brittle than aluminum, but it's also much lighter. Kind of like steel vs. aluminum, though not quite that drastic of a difference.

A wider, shorter rim would be weaker radially, but stronger/stiffer axially.
 

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Discussion Starter · #7 ·
Cloxxki said:
I'm guessing 20mm outside, for such a tall and light rim?
Nice road rim ;-)

I'd be interested to hear what the advantage is that mag holds over al in such an application, is it much stronger?
Also I wonder if the height is just there for aerodynamics, or vertical stiffness. Most road rims are way narrow, but wouldn't a wider, lower rim of the same weight be stiffer?
It is 20 mm outside width. This is meant as a road rim but I thought some might use it for a 29'er because it is very strong for being so light.

I am working on getting a 24 mm wide disc rim made out of magnesium that would weigh about 365 grams. It will take a while before I do that because I would have to order more then I am prepared to do right now to get it made.

If I got 50 people wanting to pre-order it would change things.
 

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Ligero said:
It is 20 mm outside width. This is meant as a road rim but I thought some might use it for a 29'er because it is very strong for being so light.

I am working on getting a 24 mm wide disc rim made out of magnesium that would weigh about 365 grams. It will take a while before I do that because I would have to order more then I am prepared to do right now to get it made.

If I got 50 people wanting to pre-order it would change things.
I'd be good for at least 2 sets.
 

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Sounds like THE ticket to build a weightweenie 29" wheelset, without going too underbuilt. Hopefully a great gramsavings per extra dollar spent over the similar VXC's (460g, +95g) and Mustangs (490g, +125g). This IS the sort of difference that you feel under the pedals immediately, racers will love it. I hope you find pre-orders for it. Many 29" lovers on here seem to have very healthy bike budgets...
 

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I got some rims with very similar logos to that from Alex (rim manufacturer) a few years ago. 1 set of road rims, 1 set of mountainbike rims. We had them built up for a show bike. We did this before we tried getting tyres on them. We couldn't. Bead seat diameter too large.

Still sat in Doncaster, unridden :-(
 

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Corrosion?

I remember that Merida and Paketa, and maybe some other magnesium frames as well came with lots of touchup paint and instructions to fix all scratches in the finish like ASAP - apparently they were worried about corrosion with the Mg/Al stuff (which is, I'm assuming, what this is, since pure magnesium would be pretty flimsy as well as deadly dangerous). I would wonder about using rim brakes on something like that, as well as dings/scratches in general - wheels and rims get really wet at times.

I also got some Magnesium tubing literature from Reynolds once where they warned specifically about setting your shop on fire with the chips when mitering, explosive dust, etc, etc, which really made me a lot less enthusiastic about it.

Any word on the potential corrosion issue? Have these rims actually been ridden for a while, or are they basically prototypes at this stage?

-Walt
 

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Walt said:
.....apparently they were worried about corrosion with the Mg/Al stuff

....about setting your shop on fire with the chips when mitering, explosive dust, etc, etc,...

-Walt
Mag alloys corrode like hell. Magnesium is highly reactive to water, which the air is full of. Actually, when they weld under water, they're just exposing mag rod to the water, and it explodes with such heat that with the right feed rate, it creates a weld. If you can ensure your bike part wont get scratched or nicked, mag is great. Remember what those lovely rockshox mag21 lowers looked like after you'd clamp wheels in them a few times? A little paint would chip off, and the corrosion snakes its way up under the rest of your paint. And that particular alloy was chosen for its corrosion resistance. It is incredibly stiff though which is good for things like fork sliders since you don't want your internals flexing around. But this stiffness comes at a cost, and as for rims, I think a more ductile material is advantageous when it comes time to hit some impacts & true them. At least carbon is tunable toward this end. But that's just theory. I'll be interested to see how they ride.
 

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Discussion Starter · #20 ·
flyingsuperpetis said:
Mag alloys corrode like hell. Magnesium is highly reactive to water, which the air is full of. Actually, when they weld under water, they're just exposing mag rod to the water, and it explodes with such heat that with the right feed rate, it creates a weld. If you can ensure your bike part wont get scratched or nicked, mag is great. Remember what those lovely rockshox mag21 lowers looked like after you'd clamp wheels in them a few times? A little paint would chip off, and the corrosion snakes its way up under the rest of your paint. And that particular alloy was chosen for its corrosion resistance. It is incredibly stiff though which is good for things like fork sliders since you don't want your internals flexing around. But this stiffness comes at a cost, and as for rims, I think a more ductile material is advantageous when it comes time to hit some impacts & true them. At least carbon is tunable toward this end. But that's just theory. I'll be interested to see how they ride.
I was worried about corrosion as well. Whatever they mixed into the magnesium for these rims has taken care of the corrosion problem. They will corode slightly but nothing like Rock Shox lowers or those Easton mag stems.

I have had water sitting on the brake suface since yesterday afternoon. I wiped it off the this morning and there was a dull spot that wiped off with the water and the best part is no explosions.
 
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