swama07的部落格

The new chainset uses the same Hollowglide technology first seen on Dura-Ace 7900 - a hollow outer chainring which is said to be lighter and stiffer, and to provide better power transfer and shifting. It also has Hollowtech II crank arms, outboard bearings and a fixed axle. It's available as a double (53-39T or 52-39T), triple (52-39-30T) or compact (50-34T), and with 165, 170, 172.5 or 175mm crank arms. Claimed weight is 785g (double with 170mm arms and integrated bottom bracket).

Front derailleur

There are two new front mechs - FD-6700 for double and compact cranksets and FD-6703 for triples. Spring tension has been reduced for lighter and smoother shifts, and the cage has been redesigned so less trimming is needed. The derailleurs feature a wide inner link with two pivots for extra rigidity and an improved chain guide design. Weight is 89g.

Rear derailleur

The RD-6700 rear mech is available with a short or medium cage. The SS (short) version can cope with sprockets up to 28T. The GS (medium) version is designed for use with a triple chainset and boats a wide outer link design for extra rigidity and a composite plate body which helps reduce weight to 190g.

Dual Control levers

The new ST-6700 Dual Control levers have composite blades, reach adjustment and cable routing designed to be run underneath bar tape. A new pivot location is intended to provide improved control when riding on the hoods. Claimed weight is 445g per pair.

Brakes

The Dual-Pivot caliper brakes feature the same brake shoe compound found on Dura-Ace 7900, which Shimano claim provides 100 percent more power in the wet and 20 percent more in dry conditions. They have a new arch, and cable routing has been altered so friction is reduced and they are compatible with a wider range of frames. The brakes have adjustable spring tension and toe-in. Weight is 317g per set.

Cassette

The new CS-6700 Hyperglide cassette will be available in five combinations - 11-23T, 12-23T, 12-25T, 11-25T and 11-28T. Weight is 208g (11-23T).

Chain

The CN-6700 chain features redesigned, perforated plates and weighs 267g. It can be joined using a SM-CN79 reusable link.

Wheelset

The WH-6700 scandium wheelset is compatible with both tubeless and clincher tyres, with 16 straight-bladed, straight-pull stainless steel spokes at the front and 20, laced two-cross, at the back. The steel freehub body is compatible with eight-, nine- and 10-speed cassettes. Weight is 1,652g per pair (695g front, 957 rear).



Hubs



The hubs have labyrinth seals and are colour co-ordinated to match the rest of the Ultegra groupset. Separate hubs will be available with high-quality sealing and cup-and-cone bearings. The front (HB-6700) weighs 156g and the rear (FH-6700) weighs 354g.

Pedals

The PD-6700 pedals are identical in function to the current PD-6620 - the only changes are cosmetic. The double chainset version of the groupset should be available from July, with the triple chainset and wheelset following in September.