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Bosch eBike 27 Speed Sram Dual Drive 2014 Electric Bikes
By Martin Brown |
I previously blogged about the New 2014 Haibike Trekking SL electric bikes we have arriving shortly (Jan) 2014. But these eBikes were worthy of another blog post. The reason being they are not only the only Haibikes but also one of the only eBikes out there to feature the Sram Dual drive with 27spd.
Now we all know that the Bosch eBike system is only capable of running one chainring on the front. This then only leaves the rear sprockets to play a part in the gearing, commonly 8, 9 or 10 speed. This is where the Sram Dual Drive comes into play, the basic concept is to use a 3 speed hub gear and then mount a 9 speed cassette onto the outside. This then allows the user the whole 27 gears, giving a much wider range. It's a unique system that combines the 2 types of gear system we know today. Both the hub and derailleur gearing are controlled off the same shifter, meaning you can change all 27 gears with just one hand and one set of controls. It's really simple. This gives a massive range and is ideal for trekking / commuting / touring / hybrid style electric bikes.
The gear hub can be shifted at any time, even under load or standing still. The cassette provides a wide range of gears for maximum versatility. It's built for the rider who needs lots of gearing options for touring or hilly terrain. Haibike have incorporated this system onto their Trekking SL models, available as a low step or cross bar model - Crossbar Model - Haibike xDuro Treking RX Cross 2015 , Low Step Model - Haibike xDuro Treking RX Low 2015