Science breaks new ground and engineering steps in to build the infrastructure. Noticing the genius of the self inflating tire could be a completely game changing product and one that ultimately advances future products. Don't just listen to us ramble on, peep the video and then go over to kickstarter.com to help fund a product that might eventually make its way over to the motorcycle realm.
About this project
Imagine taking your bicycle out of the garage and never having to fill up the tires or even check the pressure. Or imagine yourself being able to change your tire pressure on-the-fly with a simple adjustment from the handlebars. Our project is to bring two self-inflating bicycle tires to market, the City Cruiser and City Pro. Both tires are intended for the urban cyclists and both tires incorporate the patented PumpTire technology.
With your help we can bring this patented technology to cyclists everywhere!
Why Bicycle Tires Lose Pressure
Bicycle tires lose pressure due to air molecules diffusing through the rubber sidewalls. This requires cyclists to fill their tires on a fairly regular basis due to the high operating pressures (up to 120 psi) and thin sidewalls of most bicycle tires. PumpTire solves this problem by incorporating a pumping mechanism directly into the tire. And this means ... fewer pinch flats, no more pumping, hands stay clean, less time getting ready and more time on the saddle.
Overview of the PumpTire System
Each PumpTire set consists of 3 components – a tire, a detachable valve and an inner tube. Unlike traditional tires, the PumpTire inner tube clips into the tire to enable air to pass from the tire to the tube. When the pump is working, air moves from the atmosphere, through the valve and into the lumen surrounding the outside of the tire. From there the air is pushed into the tube. Once the desired pressure is reached, the valve senses the increase in pressure and closes the air pathway so no more air is pumped into the tire. The system works on normal rims and does not require any special equipment or modifications.
The valve assembly works by simply screwing it into the valve stem on the inner tube. Although the valve stem looks similar to standard Presta/Schrader stems, it’s actually a custom design that allows air to enter the tire before being pushed into the tube. The valve is either a fixed pressure valve that shuts off once the desired pressure is reached or it’s a user adjustable valve as shown in this drawing. Turning the valve, adjusts the pressure higher or lower to reach the desired setting. The top of the valve has an air inlet and is compatible with Schrader or Presta fittings to use with a traditional pump if desired. A filter keeps dirt, water and other debris from entering the tire.
City Cruiser for Casual Riders (26" x 1.5" tire)
The City Cruiser is designed for the casual, urban cyclist. It’s a 26” x 1.5” tire with a set pressure valve. The pumping mechanism will pump from a flat up to 65psi. It has a moderate tread design and is intended mostly for pavement.
City Pro High Performance Tire (700c x 28mm)
The City Pro is a high performance tire with a 100 psi maximum pressure. It’s a 700c x 28mm tire. The tire works in conjunction with a high performance user-adjustable valve which allows the user to set the pressure from 65-95psi. This tire is designed for the avid cyclist who is constantly seeking better performance from themselves and their equipment.
