1991 Specialized Stumpjumper M2
Beginning in 1991, the debut of the Stumpjumper M2 was a big departure for Specialized as their first bike with a frame that wasn't at least partially made of steel, as had been the case for 10 years prior. With M2 standing for Metal Matrix composite, it was an aluminum alloy (a metal) combined with a mixture of aluminum oxide (a ceramic). Aluminum oxide is a form of sapphire and an extremely hard and abrasive substance, as used in sandpaper. Rather than using metal saws to miter the tubes, which would have worn out quickly, the manufacturer needed to grind them to fit. Although the end result looked a lot like many other aluminum frames with fat welds, the extra strength of the material allowed them to use less of it to save weight. The Team build with Suntour XC Pro was the top of the line, but its silver paint was no match for the Shimano Deore XT bike one step below with pearlescent violet paint. The example shown here was custom built up a year later with a Shimano XTR M900 group and a host of aftermarket parts with violet anodizing. Although some of the parts were manufactured a bit later, it was almost as if the frame was mean to be built up this way with an overload of purple. It should come as no surprise to many that the Ringle Moby seatpost split open with almost no use. The later Team Edition saddle was a collaboration with WTB, and the plastic body pedals with titanium spindles were a later product of the S-Works program. As shown, the bike weighs a touch under 24 pounds.
The Build
Year: 1991
S/N: 91T03706 Frame: Specialized Stumpjumper M2 Fork: Specialized Direct Drive Stem: Answer ATAC Headset: Shimano Deore XT M736 Bottom Bracket: Shimano XTR M900 Handlebar: Answer Hyperlite Shifters: Shimano XTR M900 Front Derailleur: Shimano XTR M900 Rear Derailleur: Shimano XTR M900 Brake Levers: Shimano XTR M900 Front Brake: Shimano XTR M900 Rear Brake: Shimano XTR M900 Crankset: Shimano XTR M900 Chainrings: Shimano XTR M900 26-36-46 Pedals: Specialized S-Works Titanium Hubs: Shimano XTR M900 Rims: Specialized X23 Tires: Specialized Ground Control 1.95 Specialized Ground Control Extreme 1.95 Wheel QR: Ringle Ti-Stix Seatpost: Ringle Moby Saddle: WTB/Specialized Team Edition Seatpost QR: Ringle Ti-Stix Grips: Grab-On MTN-2 Cogs: Shimano XTR M900 Chain: Shimano HG Bottle Cages: Ringle H2O |
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