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There are Magnesium hutch hubs above ..yes

but these are 1st  generation after Titron ........HUTCH made hubs!
One still has the protective Matte grey finish that was to protect the magnesium the front one the ebay seller started to remove it . Awsome hubs Titanium axles 11 1/2 oz  total combined weight .

they weigh nothing and spin incredible even without being on a rim . 




Original 1st gen decals!

Last edited by 79supergoose (2010-04-27 9:56am)

Hi guys!
I'm new here.  I'm an old-school Hutch guy who has a way to tell for 100% sure whether your hubs are Magnesium of Aluminum (actually there are two ways, but one of them you DO NOT want to do).
  First, just to get my chops so you know I'm not a poseur, I'm 43 years old and raced BMX in the '80s in NY on a black Hutch Pro Racer I built up with my paper-route money. ( You had to deliver  A LOT of newspapers, even back then, to build a pro bike.)  SE Landing Gear chrome forks (sorry Hutch, but the LG was a better fork)  / black Hutch magnesium hubs with titanium axles (exact like the bottom hub in the pic at top of this thread) / black ACS Z-rims (heavy, but indestructible) / black spokes / chrome SunTour 16T freewheel / chrome Hutch bars (after I bent the black alloy Race, Inc. ones) / Redline block neck / black California Lite 3-piece pad set / black Dia-Compe MX1000 brakes / black Dia-Compe Tech-2 levers / black Oakley F-1 grips with white sleeves / chrome Izumi chain / Takagi 180mm Cro-Mo 1-pc cranks (I broke my friend's Super Maxys on a jump, so I didn't trust 'em, and couldn't afford Flites) / black 44T Pete's Precision Products chainring / black Shimano DX platform pedals / black original Uni-seat (not the aero one), and for rubber Compe IIIs of course, 2.125 front, 1.75 rear.
And for races, a Pro-Tec helmet, originally with with QR strap ( I started racing a couple years before the ABA made double D-rings mandatory)
  I've still got the bike, which is no longer pretty due to years of racing, thrashing, mega-jumping and living near mean salt water. Unfortunately, during a move several years ago I lost the front hub & rim while in mid-restoration.
   Now that you know my bike, you know me, so here's how to tell Al from Mg hubs:
   All you have to do is measure the specific gravity. You will need a scale capable of measuring to the tenth of a gram or better, and capable of weighing something suspended from a string. The venerable Ohaus triple-beam scale is perfect, though you could also rig a cheap digital scale to work with a little ingenuity (hint: you'll need a chair, a stick and some more string) The only bummer is that you need the bare hub in hand, so it can't be part of a built wheel. The hub must be fully disassembled and the bearings removed so you have ONLY the bare hub shell left.
  Specific gravity is the ratio of the item's weight divided by the difference between it's weight and it's weight in water. Basically, first you just weigh the hub (we'll call this it's weight in air). Next, suspend it from a string attached to the scale, submerge the hub completely in a bucket of water (without it touching the bottom), and note it's weight while submerged (we'll call this its weight in water.)  You will now have two measurements, weight in air and weight in water. Divide its weight in air by: its weight in air MINUS its weight in water. The result is the specific gravity, SG. If you like formulas, this can be expressed as:   SG = Wair / Wair - Wwater.  If you're not good with math, the only important thing is that you do the subtraction part at the bottom of the equation, Wair - Wwater, FIRST, then divide the top number by this result.
  The specific gravity (SG) of aluminum is 2.64. The SG of magnesium is 1.75.  Your numbers won't be exact, but the density of Al and Mg are different enough that you should be in the ballpark of one or the other.
  SG is just another way of expressing density, and by looking at the numbers you can see why Mg is so much lighter (weight is just density times gravity).
  I knew that chemistry degree would come in handy someday! :-)
As for hubs that are allegedly Mg bodies with Al flanges, I doubt it. Al and Mg cannot be welded to each other, and since the bodies and flanges are not mechanically attached (e.g. bolted, glued, etc), they will be either one or the other.

    One small caution about magnesium parts (I'm thinking of the guy with the eBay hub that the seller stripped the grey finish off of), especially if you live near the ocean: Mg does NOT play well with moisture and salt, even the salty breeze near (and not so near) the shore can corrode this very active metal (note how far to the left side of the periodic table it is). Bare Mg should always be coated with something, even clear spray paint is fine if you want to keep the bare metal look instead of painting. I've had magnesium dirt bike parts dissolve into mush after a flood. Ditto for any aluminum alloys containing high amounts of Mg such as 7075 Al. That's why 7075 is always anodized. Leave a pair of high-end road bike wheels with lots of brake pad wear on your damp basement floor for a year and they will start to pit heavily then dissolve into mush. I mention all this only 'cause I don't wanna see anyone's nice bike ruined because their girlfriend wouldn't let them keep it in the bedroom. (Use the attic or get a new girlfriend.)

   Hope the science lesson helps someone get the 411 on their hubs.
----Hutch138

Or you could just weigh them on a scale, the Al weigh 14 1/2 oz a set versus 11 1/2 oz a set for the TI/Mag.

More pics of some Mag / Ti hubs.  All original.  Pretty nice survivor condition.

Here's Mines!