March 12, 2005; The Birthday Tour, N. Cascades, WA

So, did they work, and how were they? Show everyone proof that your ride was a success (or even a complete failure)!

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bigKam
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March 12, 2005; The Birthday Tour, N. Cascades, WA

Post by bigKam »

Kelvin and i finished the Ahma BCs earlier in the week. this is the second pair of asymmetric skis we've built. in addition to having different sidecut dimensions for the inside (24m) and outside edge (21m), we made the shape of the tips and tails asymmetric, too. the reasoning for shaping the tip/tails is to help reduce scraping of the topsheet material near the tip/tail area by the inside edge of the ski. but if anything, the shape looks pretty cool.

the Ahma BCs were designed more for the backcountry. what do we mean by this? basically, we wanted a ski that was fairly lightweight for touring. the original Ahmas were quite wide (135mm at the shovel) and heavy, and so we wanted the new pair to be narrower, hopefully lighter. but for some reason, we didn't pay much attention during the drafting phase and our template came out to be 132-105-119mm! in the end, the Ahma BCs were a bit lighter, but not by much. anyway, here are the basic specs of the skis. the core is made of poplar and maple. mixing poplar helped reduce the weight. at cord-center, the core is 11mm thick and 2.5mm at the tail and 2mm at the tip. we used a thin sheet of black ABS for the topsheet. to improve bonding of the topsheet, we abraded the ABS, but i don't think we abraded enough. i won't be surprised if they delam soon. the other materials include two layers of triaxial braided fiberglass (22 oz.) and rubber damping strips. i used three damping strips, one over each edge and one strip down the middle. and finally, we used black base material. compared to the original Ahmas, we left out the two layers of flannel material. this really helps make the skis lighter as the flannel soaks up a lot of epoxy!

the Ahma BCs look pretty cool overall and they have a nice even flex. the first test ride was in the backcountry in the north cascades. i skied them on my birthday, on The Birthday Tour to be exact. below is a photo of the skis near Early Winter Spires at Washington Pass. notice the shape of the tips, but they are actually skied with the right ski in the photo on the left side, and the left ski in the photo on the right side.
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snow conditions ranged from soft corn (on sun-direct aspects) to bullet-proof refrozen corn (on shaded and north, northest aspects). when i was making the first set of turns, i immediately noticed the difference in sidecut between the inside and outside edge. the skis were very quick edge-to-edge; they were very responsive and held a great edge (probably because i had them tuned). they felt lighter compared to our original Ahmas, and this made somewhat of a difference, both during the ascent and while i was trying to whip them around on the descent. overall, the skis performed really well on an icy pitch that we had to ski to get back to the car. the only thing that i did notice is they seem to resonate a bit. it's not a big deal, but i think the skis need more damping elements to make them feel more quiet.

more photos from the trip can be found here and here.
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