24 January 2007 - 23:50Weight Loss
When it becomes so cold, that you loose any motivation to do anything outside, the mind begins to wander….
And constantly being around bikes always has me looking for some way to upgrade.
And knowing that it will take me an entire summer to loose 4% of my own mass, I decided that one of my bikes was looking a little porky.
And owning a bike shop, and being somewhat of a bike nerd, and having an already sweet bike, weight loss becomes difficult.
See, I like my things a certain way. And being in the “Clydesdale” category, certain products just won’t work.
While skinny little sub 160lb guys like Ponte or Maggs can easily roll around on rigid single speeds hovering about 19lbs, tubbos like myself get to ride heavier bikes. At 2**lb and probably gaining, I can’t use a carbon fork. I shouldn’t use Ti anywhere on my bike except for the bolts that hold my bottle cage on. There are certain types of spokes I can’t use for fear of my mass turning my wheels into a pretzel with the very thought of riding them.
So we now get into the sport of hair splitting.
How light can you really go?
Before your spouse starts to make fun of you. Or you run out of money.
Well, Kermit tipped in at 24.49lbs, with my pedals, Time ATAC carbons. I always weigh my bikes with pedals, because you can’t ride without them. Certainly not heavy by any means.
As built, it is a large Niner SIR 9 frame, with a rigid Niner steel fork, King headset, Avid Juicy 7 brakes, Thomson stem and seatpost, On-One Marry bars, an old, tired, but true SDG cow saddle, old XTR (952s) with a Spot 35 tooth spiderless chainring, SRAM PC-68 chain, Niner 21 tooth cog, and a Bike 29 Royale Single Speed Wheelset, laced to Salsa Delgado rims. The tires are WTB Weirwolf LTs.
Pretty darn respectable really, considering that it has a steel frame and fork.
So what can be done to lighten the chassis?
I started with the wheels.
One of the key places to loose weight is in your wheels. Heavy wheels make for a heavy feeling bike, because you have these two big spinning masses that don’t want to do much except spin and roll in a straight line. Great if you don’t have any turns, and have a whole bunch of time and energy to burn getting them up to speed. Turning heavy wheels takes more energy, and making them change direction is work. Making them slow down is also more energy consuming, requiring more effort at the brake levers.
In short, heavy wheels are not so good.
I hated to do it, but for the sake of progress, I had to destroy a perfectly good set of wheels. Rims are always cheaper than whole wheelsets.
The old equipment:
King ISO disc front, King SS disc rear, DT Super Comp spokes front (triple butted), DT Competition rear (double butted), alloy nips, laced 3 cross to Salsa Delgado 32 hole rims, with Velox rim tape.
850g front, 1070g rear, weighed without brake rotors, tires or tubes, QRs or mounting bolts.
The new equipment:
Same hubs, but this time laced to Stan’s new ZTR Arch rim, using DT Competition (double butted) spokes on both wheels with the same ole’ alloy nips. In place of the rim strips, I used Stan’s Yellow Tape.
830g front, 1000g rear.
A savings of 90g in just the wheels. That is almost a 1/4lb. A cheeseburger if you will.
Yeah, but there are still the tubes right? And the heavy tires that you like and…
Tubes? um, no. No tubes.
Or should I say NoTubes?
The tubes I’m using weigh about 210g each. What if I could just get rid of them?
Well I did. The Yellow Tape and Stan’s rims are co-developed to provide an air tight seal, and the rims themselves are designed to hold the bead of the tire more securely than a conventional rim might. Tech can be found here.
The only thing keeping the air in the tire is the liquid latex sealant, that also must be added.
So, in the wheels, I really got to loose about 1/2 lb. Because of the tire I’m using, a high volume 2.55, I had to use more of the sealant, which unfortunately adds weight.
I also decided that I would pull out my old “light” brakes out of retirement, and put them back into service. The Magura Marta is a pretty light brake set, light enough for me to drop another 200g off the bike, just by switching brake systems. We have some alignment issues with these brakes, and we are waiting to see if I can even keep them.
I am going to put another few minor mods that might scrimp me a few grams , but really, this is as light of a bike that someone of my size should feel OK about riding.
Current weight, a bomb proof 23.53lbs. Final weight to come before riding season starts.