I NEED…. I WANT…
This project started off as an “I need” project. I cycle to work, mostly off road, doing 28miles per day. I have a few singlespeed mountain bikes, but lately everything seems to be wearing out or breaking, due to the relentless British weather.
I need a bicycle I can rely on. One that can ride distances further than I am capable. This bicycle needs to be light with a modern take on simple functionality.
I want a bicycle that will take belt drive, so I set about designing around Gates Carbon Drive CDX. I want a cross country 29er that will take hills in anger and descend with confidence. I want a frame that is stiff yet compliant. A frame that will let me rip my legs off.
What I get….
I have been a singlespeeder for over 17 years. Singlespeeds are popular over the winter, but only a few have designed frames around the belt-drive. The Frame design needs to have the chain-stay length calculated. I have designed my frame chainstays to fit 39:20T (1.95 fast) to 39:24T (1.63 low). Refer to the picture, I am splitting the frame along the dropout for several reasons.
Belt Drive Pros:
• Belts perform extremely well in British conditions like mud, clay and wet weather.
• Gates Carbon Drive CDX belts have a great reputation for logging long distances.
• Belt drive is very low maintenance, not even needing oil.
• Gates CDX belts and sprockets are exceptionally light.
• Gates CDX belt keep the alignment without “worming” off the sprockets.
Derailleurs designs have “evolved” from road bikes (intended use) to be used for mountain bikes. However the whole drivetrain is exposed on a mountain bike leading to a shortened chain and sprocket life. Not the best system to be running through mud, grit and water
• Expensive: When the chain wears out the sprockets often need changing too.
• High maintenance: Lack of gears when the cable becomes clogged with mud.
• Vulnerable: The rear mech is vulnerable to damage by hitting trail obstacles.
• Adjust shifting: Can drop the chain in between the cassette and the spokes.
This may seem a little harsh, when a lot of people have no issue and are happy to maintain and clean their bicycle. However I am looking for a system that can be relied on and does not need the drivetrain to be replaced every season. I am questioning also questioning the extra weight needed for the luxury of gears when singlespeed is so reliable. So you might have to walk up some of those hills. At least you don’t have to push all the way back due to a drive-train component failure.