Thursday, March 20, 2008

18lbs, here we come...

Anyone who knows me in a bike context probably knows that I'm what's called a "weight weenie". I like light bikes, always have, back from the days when I was younger and bought a gram scale from a coworker at the bike shop. It was a scientific beam scale -- more accurately a "balance" and had a range of 0-300g with a resolution to .01 grams. In retrospect I probably should have wondered why he had a gram scale accurate to .01 grams... but I never did... I was just happy I could weigh my stuff. Using that I had my Cannondale road bike down to 18.5 lbs, which at the time actually WAS an accomplishment.

Oh, and yes, I recorded every part I weighed in a notebook, and listed the weight all the way down to a hundreth of a gram. That should give you a pretty good idea of how I approached things. I would weigh 10 bolts and use the two lightest... even though we're talking a 10th of a gram difference.

For a while, my weight weenieism was in remission... probably had something to do with me owning a Rocky Mountain Element, which was going to be heavy no matter what. Recently, however, it's been flaring up... first with Grace's Santa Cruz, now with her Scott. I had her Santa Cruz down to 22.8lbs, which is REALLY good for a full suspension bike. But when we got her the Scott Scale... well, look at the name... the "Scale". You know this is a bike made specifically for weight weenies, and you also know you can't go hanging heavy parts on it.

So, with that in mind, I built it up using what we had on hand, and it came out to be around 20lbs... just a little over. I wound up stealing more and more parts from her Santa Cruz, and as it stands right now, the bike hangs from the scale at 20.00lbs. DAMN!

Well, there's hope. To fit the bike to her, I was using various stems that I had on hand, and the one that wound up being the most comfortable was a 105mm no-name brick of polished aluminum that weighs in at 170g. I just ordered up a 106g Syntace F99 -- she's got a 90mm on the Juliana already. So that's 64g.

Next, I convinced her to let go of her trusty Panaracer Fire XC Pro tires. They're reasonable at 580g, but the Kenda Karmas she'll be trying are 450g -- 130g lighter a piece, for 260g total reduction, and at the wheels where it makes a bigger difference. I ran those tires for most of last summer, and thought they worked great, so she should like them better than the Schwalbe Racing Ralphs we tried a while back.

Another big difference will be in losing the e-type LX front dérailleur. Right now I am using the front derailleur as a chain guide, since the bike is set up as a 1x9. At 185g, that chain guide is almost as heavy as the downhill/freeride/4x chainguides available now! Plus, I run an outboard "ring guard" to keep the chain from jumping off to the outside... and even as a lightweight Spot guard, it's still 60g. Ditch the two of those, and you're looking at 245g of weight saved! I'm currently talking to a guy in Canada who has a carbon fiber chain guide which weighs in at around 10g!

Finally, I'm looking to replace the full run dérailleur housing with Nokon housing and a special rigid aluminum tubing I've been testing on my bike.

With all these changes -- the bike should wind up under 19lbs... my estimates are at around 18.6lbs! That's for a mountain bike... and it's in the same range as my old Cannondale road bike.

Awesome!

1 comment:

Andrew said...

Backpackers also play this game:

http://spreadsheets.google.com/pub?key=pgqiXApGfQ06T3N-b48zVCQ