Wednesday, February 20, 2013

Bunyan Velo

Over the years, I've been asked to contribute writing and/or photos to various online publications and blogs and such, but mostly I have chosen to not participate. Bunyan Velo seemed different, better, and it turns out that it is, in fact, an exceedingly well-done thing. I'm thrilled and honored to be part of it. Lucas W, who created BV and marshaled the herd of cats who contributed, should be proud of this accomplishment.

Read it.

Tuesday, February 19, 2013

Opinions on fat tire bikes

This article about "Pondering the Point of Snow Bikes..." has been getting some buzz in my usual corners of the interwebs today. I doubt I'm alone in thinking that the author is basing his rather strongly stated opinions on minimal experience coupled with unrealistic expectations and myopic prejudices. Frankly speaking, I've read that blogger's writings on various bike subjects over the years, and have generally seen a similar pattern of sharp criticism and suggestions for technological improvement springing from only the most rudimentary knowledge and experience. It takes all kinds, and the internet is full of kooks, present company excluded, of course. Don't believe everything you read, especially about bikes. My opinion: my Pugsley is quite likely my most versatile bike, and I can do many fun things on it that I can't do on my other bikes. Lots of avid cyclists "don't get it", which is fine with me - I don't "get" the popularity racing road bikes. It's ok.

I loathe the term "snow bikes", because fat tire bikes can be ridden ANYWHERE any other bike can be ridden, in any season. Yes, the fat bikes positively shine in a variety of winter scenarios (but NOT all winter scenarios), but they also work great in sand, loose leaves, tree debris, rocks and loose gravel, and on other surfaces where most cyclists wouldn't consider riding a more conventional bicycle. I've been riding my Pug recently about 30-50 commuting miles per week on paved roads and trails, and it's fine and fun and not nearly as slow and ponderous as an armchair expert might expect.

Some friends and I went for a nice ride on Sunday. First we hit this trail along the river near my house:
In the summer, this trail is sandy, which makes it somewhat hard to ride on a normal bike, but a fat bike rides over sand like it's a paved road.

And we continued down onto the edge of the river, where the "trail" was more like a smattering of human and canine footprints.
This snow wasn't well-packed, and the tires sinking through the crust made it more challenging than the buff single-track we'd just finished riding. But at low pressure of less-than-5psi it was ridable. The know-it-all "fat bikes are a fad" types don't understand how GREAT it is to just ride off in interesting directions, even if nobody has gone through the trouble of building a trail and a parking lot there. I do believe that this surface would have been impossible to ride on a typical, non-fat offroad bike. Under the snow, I happen to know that the river's edge is strewn with large rocks, driftwood, sand, and other debris, making it nearly impossible to ride on a normal bike ANY time of year. Fat tire bikes open up riding opportunities that simply don't exist with other flavors of bikes.

After we completed our loop, we'd worked up a powerful appetite, and settled on lunch at a dive-ish bar in my neighborhood. I chuckled as I imagined what passers-by might think of the collection of bikes we locked up to the light pole outside.

Friday, February 15, 2013

Fat tire tubeless conversions

Mountain bikers have been using various tubeless systems for years now to save weight, improve puncture resistance, and/or to reduce rolling resistance. There are various tubeless systems for various rims and tires, but nobody has a commercial tubeless kit for fat bikes. We found some fat-tubeless how-to advice on the internet, and decided to pair this advice with our own dead reckoning to roll our own fat tire tubeless kit.

Here's a fairly standard modern-day Surly fat rim, a Rolling Darryl in this case. This is a 82 mm wide single-wall rim with cutouts and a Surly PVC rim strip sized for this rim. The rim has a somewhat deep channel that we decided to fill with a strip of foam insulation. The ideal width is just barely wider than the cutouts, just enough to fill the rim channel. A little packing tape holds the foam in place.

Next, slightly inflate a really fat 24" tube and stretch it over the rim, putting the valve through the valve hole in the rim in the usual way. This one is labeled 24x2.4-2.75", which is wide enough for rims up to 100 mm. Once the tube is in place, start laying it open with scissors, as shown here.

After cutting the tube open, it should look like this.
Then put the tire on over the split tube such the the tube is between the tire bead and the hook of the rim. The tube should stick out the sides, like this.
Now pump up the tire to make sure the tire can seat on the rim with the tube pinched between the tire bead and the hook on the rim. It might be tricky to get the bead to seat since the air you pump in isn't contained by anything. An air compressor helps.

Once you've verified that the tire will bead and hold air without a tube, let the air out, and pour in some Stan's NoTubes sealant. We used three 2-oz scoops per tire. You can also use the injector to squirt sealant into the valve, but the high volume required makes this a tedious process. The funnel is faster.
As before, seat the bead and inflate the tire again, exercising care not to spill the sealant fluid. When you're confident that the tire is seated, shake and spin to ensure that the sealant works it's way into the nooks and crannies between the rim and tire to seal any potential leaks.
Finally, trim the protruding tube with a sharp razor or knife. Careful not to slash the sidewall on your $150 tire. When you're done, it will be difficult to know that this any different than a standard tube set-up.
Inflate the tires to near-max pressure (25ish psi) and wait a day or two to make sure they're holding air. Then go out and ride it:
I've been riding tubeless on my pugsley for a couple weeks now. Weight savings over the usual Surly 26x4 tubes is about 50g per wheel, which by itself is probably not worth the effort, especially since there are substantially lighter 26x2.7" tubes that seem to work for some people. Initially, my motivation was not weight savings, but puncture resistance, which will be nice for summer off-trail woods riding, the urban jungle, or vacations in the thorny desert. Now after some experience I'd add another motivation: I think the tires roll better, especially at squishy low pressure, since there is no tube flexing inside the tire to increase rolling resistance.

We could perform this service for you. Parts and labor for two fat wheels would run about $120.

For more on tubeless, see some of Stan's videos. I especially like the Puncture Demo video.

Wednesday, February 13, 2013

Surly Bastard!

You may recall that I spent some time on a Surly Troll awhile back. That was a really great bike, but I'm compelled by the standards of my chosen profession to keep up with new products. Therefore, the Troll was sent to a new home, and replaced with the Disc Trucker that I rode in my recent adventure in California.

Anyway, the Troll's 29er big brother, the Surly Ogre has intrigued me since I first heard about it. But a person of normal means can only buy so many bikes, so I procrastinated. Then Surly presented us with the fat-tire 29er Krampus and the corresponding 50mm wide Rabbit Hole rim. Unfortunately for me, the Krampus is fun to ride, like a fast fat bike, but lacks braze-ons for racks and other accoutrements. In my twisted mind, outfitting an Ogre with Rabbit Hole rims and "normal" 29x2.4" tires was the best of both worlds. As the project was coming together, I discovered that Surly had created, but not publicized, a Krampus fork with the same braze-ons that are included on an Ogre fork. It's 15 mm taller but has a few mm more offset, so it seems like a reasonable substitute, in terms of that mysterious concept known as steering geometry. Without cantilever braze-ons, the Krampus fork is actually 50g lighter than the Ogre fork, even with the canti posts removed. We started with a 29x2.2 Schwalbe Racing Ralph in back and a 29x3 Surly Knard in front. I present the Krogre:

Those are Natril Gear panniers on a Tubus Duo rack. We sell all these items, by the way. Side note: the world needs more camouflage bike accessories.

I just received some Maxxis Ardent 2.4" tires to tie it all together. Here's the result:
Once I settle on a tire I like, this will probably get a home-brewed tubeless conversion, like my Pugsley.

Tire clearance is considerable in front, as you'd expect:
It should be noted that a standard Ogre fork has enough room for a 29x3 Knard, ya know, if you're into pushing the limits of your equipment. Or you can just get one of these Krampus forks.

The 2.4" Maxxis Ardent on the wide Rabbit Hole rim is no problem in back. Clearance in the frame is fine, and there is enough chain clearance to run a triple and a standard unmodified cassette. Measured tire width on this rim is approximately 64 mm, about 1 cm skinnier than a Knard 29x3 on a Krampus. That 1 cm may or may not sound significant, but it does constrain the number of chainrings a person can use on a Krampus - most Krampi have a 1x9 or 1x10 set-up to deal with the chain clearance issue.

The red rim strips lend a touch of class, which is really what this is all about.

Friday, February 8, 2013

Closed Saturday Feb 9

We'll be closed Saturday, Feb 9!

When I get back next week, I'll show you some cool stuff.