As a number of riders in this year’s Tour de France can attest, getting a flat after hitting a tack or nail on the road not only causes delays, but can also be downright dangerous. Last year, Hutchison released its airless Serenity tire that is 100 percent flat-proof, but cyclist Steve Boehmke found they were fairly difficult to install and only fitted a very specific sized rim. To overcome this, he’s built wheelsets with the tires pre-mounted that are designed to take the hassle out of getting them on your bike.
The Serenity tire is made from a microcellular tube that fits into a specially designed tire casing. It rides like any bike tire with about 60 pounds of pressure, which is comparable to the pressure of a mountain bike or city bike. Because the tire has no air, it doesn't add rolling resistance from air loss. They weigh about 1,400 grams (3 lb) a pair and feature a reflective sidewall that provides visibility during night rides. The tires are also claimed to provide more shock absorption than typical tube tires and are rated for about 3,000 miles (4,828 km) of wear.
Boehmke founded @cme to provide custom professional grade aluminum wheelsets that come with the tires preinstalled. He explains that the Serenity tires are difficult to mount on the rims, and also require a specific rim dimension and configuration, which @cme offers. Once you get the wheelset you can put it right on the bike and be ready to hit the road. He says the tires will last - holes and all - until the tread wears out.
Pre-built wheels with the Serenity tires mounted on them are currently available in two main configurations: a 26 x 1.5-inch, which fits many mountain bikes - except for newer models with 29-inch wheels. @cme also makes wheelsets in 700c x 1.5-in, which accommodates single speed, fixed gear, and some hybrid or city bikes. The latter option comes with KT 8/9 speed freewheels and flip-flop single speed hubs, or with a hub that accommodates a Shimano coaster brake. Since the wheelsets are custom, higher-end hub configurations are available.
To get his wheelsets on the bikes of riders, Boehmke has turned to Kickstarter. At the time of writing with seven days to go, the project has raised US$1,678 of its $1,000 goal, with tiers ranging from $5 to $10,000. The estimated delivery date for those pledging enough to secure a wheelset (or 50) is August 2012.
Boehmke's Kickstarter video pitch can be seen below.
Source: @cme on Kickstarter
Say what?!
If a tire looses air fast enough for that to add rolling resistance I'd say there is a puncture :-)
Rolling resistance comes from the tire deformation that happens when it flexes. That comes from the tire adapting to the surface it rolls over and the weight it must carry.
A tire that is not inflated sufficiently flexes more and that means extra rolling resistance, thus a traditional inflated tire will see more rolling resistance over time but unless there is a puncture that will be over a period of months and it can easily be remedied by putting air in.
As a concept I like the idea of a bike that can't be hit with a puncture but such a solution must not come in a way that means extra weight. Adding even a little weight to the tires of a bike means a lot to how it rides, in fact there is no worse place to add weight to a bike.