You are bombing down a rough gravel road with confidence thanks to your 28 mm tires and skills taking your road bike off road but your chain is lively slapping around creating a racket. The threat of it skipping or falling right off the chainring can feel very real on rough terrain. Chain slap is dealt with using a switch on Shimano’s mountain bike rear derailleurs that makes the mechanism more rigid to hold the chain taut. A clutch allows the rider to choose whether the derailleur is rigid to ensure the chain doesn’t bounce around as much as it might. With the rise of mixed surface and gravel riding, today Shimano has introduced Ultegra mechanical and Di2 rear derailleurs that feature chain stabilization.
The technology was spotted on the bikes of Trek-Segrafedo at De Ronde van Vlaanderen over the weekend, a race perfect for pushing the technologies limits thanks to high speeds over the rough cobblestones of Flanders.
Rough surfaces can lead to skipping or drop chains. Pro riders bash over rough cobbles stones and gravel in the spring classics while recreational riders take their bikes onto all sorts of surfaces hoping it’s up to the challenge. As riders push their road equipment further, frames have adapted with wider tire clearance and geometry tweets to make bikes more stable on tricky surfaces. Shimano now adapt their Ultegra R8000 drivetrain for the adventure rider. The new mechanical RX800 and Di2 RX805 rear derailleurs use Shimano Shadow RD plus derailleur technology and features a switch that allows riders to choose whether the derailleur stays more rigid to prevent chain chatter, skipping and noise when riding over rough surfaces.
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With the new Ultegra RX chain stabilizer derailleur Shimano is bringing adventure back to road riding. Whether you ride Di2 or mechanical the idea is to stabilize your chain over rough ground to reduce excessive chain movement and general ‘chain chatter’. Much like Shimano’s MTB derailleurs the On/Off switch can be found next to the upper pulley. When activated the rear derailleur pivot takes a firm hold to reduce excessive movement and noise. #RideShimano #UltegraRX
The switch is located next to the upper pulley very similar to the one found on Shimano’s mountain bike groupsets. The derailleur has also been adapted to the wider gearing riders like to have on adventure bikes accommodating 11-28 to the wide 11-34 cassettes.
While the new derailleur won’t appeal to road riders who stick to smooth pavement rarely experiencing excessive chain movement, those who have bounded down rough roads will have another option when choosing how to outfit their next adventure bike.
The technology adapted from Shimano’s mountain bike derailleurs gives riders who know they will be tackling rough surfaces further confidence in their equipment. It will appeal to cyclocross racers, adventure riders and those looking for specialized equipment for taking off-road. The new technology blurs the line between the equipment that is intended for road use versus what is intended for trails.
MSRP on the mechanical Ultegra RX derailleur is US$110 and $285 on the Di2 version.