|Getting rid of that front derailleur and adding wide range cassettes has its pitfalls.|
Riders are finding this out now. New 2017 bikes with different lower end spec have been plagued by issues such as dropped chains, chains that derail when pedaled backward, and by noises and excessive wear. SRAM and Shimano have responded by making further tweaks to tooth profiles on chain rings and cassette cogs to allow chains to engage and release the teeth more efficiently, especially when coming off those big, 42T-50T rear cogs.
Basically, what has happened is that we've removed our front shifting issues and found them again on the back end.
Think about it- Big chain rings up front didn't want to release the chain or pick it up easily because there was so much more chain to teeth contact by virtue of the chain ring sizes. Now those sized cogs and bigger are found out back on many mountain bikes and the chain release issues have cropped up again.
|This Shimano patent applied for design shows an axially movable chain line. Courtesy of Cycling Industry News.|
It complicates the bottom bracket, for sure, and it puts a mechanism in a place where moisture could wreak havoc on the device. However; if anyone can engineer this to work right, I would place my bets on Shimano. Still, I am not convinced something this complex can survive the rigors of mountain biking. But we may or may not see............
|SRAM's solution also alters the chain line but does it by a floating chain ring mount. Image courtesy of Cycling Industry News|
But what really strikes me here, and actually made me laugh out loud when I first saw this, was how all this getting rid of the front derailleur was going to simplify our drive trains.
Apparently "simple" isn't working out as well as they hoped it would! But making it more complicated is the answer? I don't see this working out well...........