A long time in the works, this U.S. Patent for "Bicycle Chain Rings with Ramps" covers elements of the chainring shifting technology that we at Synthesis are working on for several years. The patent was finally awarded Jan, 2012 after several years in incubation.
This is one of several patents covering the technology behind the World's Fastest Shifting Chainrings. Originally known as 'Radical Ramp' technology, you can see the WickWerks Web Site for more on how it works. The new name is BRIDGE Shift Technology, and it was developed to the current form here at Synthesis Engineering Services.
If by some chance you think the technology is not a big deal, look who was using it. Some of the fastest riders around - particularly in Cyclocross - where these rings adorn many a bike ridden to World Cup and World Championship podiums. The chainring shifting technology is good enough, that it is our belief that if others had adopted this technology, the 1X craze would never have started.
Chainring Shifting Making A Difference
Truly, this approach to chainring shifting is superior - especially in difficult situations like muddy cyclocross. While 1X has many advantages, avoiding shift issues should not be a driver. Since with this technology the front shifting is quick, exact, and pleasurable. When adjusted properly, the chainring shifting in the front is as good as the cog shifting in the rear.
Bicycle chainrings with this technology are available for sale at your local bike shop, or at WickWerks.com. If you are a cyclist, you owe it to yourself to see what you are missing.
Follow on patents include Chainring Shift Patent No. 8,617,015 covering more of the chainring shifting areas as well as variations of the shift technology. And others too.
Synthesis Innovation
We won't take credit for everything in the patent, it is the result of ideas initiated from WickWerks, our customer, as well as from a lot of great cyclists that ride the rings and give us feedback. KFC and her husband Mark, are particularly helpful as she is the very top of cycling, and rode these rings for many years.
Synthesis is, however, the hub that brought all the ideas together to bring this great technology to market. That is what we do. Design Innovation is one of our key differentiators. Oh, and we are here to discuss your project when you are ready.
How It Works
As shown in the U.S. Patent image above, the special design of shift ramps are key to shifting improvements. The old technology lifts a bicycle chain using contact at the narrow portion of a chain link. (Lifting between the chain link pivot points.) The new technology of this U.S. Patent shows how the chain is lifted under the chain link pivot points.
The pivoting points of the chain are also the widest portions of the chain. These are the "Load Points" in the chain, because all the chain force goes through each and every pivot point. By lifting under these pivoting points control of the chain is much more stable during a shift. This makes it less likely to grind or miss the shift. It also makes moving the chain very positive and stable.
Secondly, by having a lot of shift ramps around the face of the chainring, the shifts become almost instant. Basically, it shifts when the rider "says" shift, not when the chainring gets around to finding that link to engage with. This is an important aspect of rider perceived "good" chainring shifting. Unfortunately, it's something other manufacturers have missed.
Those 2 things are the key inventive elements shown in the patent. Though there are a lot of other important details, too.