From VeloVision Online...
Alfine and Nexus 8 hubs get 'smooth' roller clutches instead of pawls...
Shimano have announced a change to their 8-speed internal gear hubs. Previously, like most such hub gears, they used a freewheel-like system of pawls to ensure one-way rotation of various internal parts:
This does of course create a clicking sound...
Now they've moved to roller clutches which are near-silent in operation:
These also offer, they say, quicker engagement, which should make shifting a little faster. This final image shows how the new hub internals use three of the roller clutches:
The 'smooth' hubs have new part numbers:
- for roller brake SG-8R31 (std), SG-8R36 (premium)
- with coaster brake SG-8C31 (std), SG-8C36 (premium)
- Alfine (for disk brake): SG-S501
Can you tell me where I can buy a SG-8C31?
thanks
Hi
I’m looking for a 7 or 8 speed internally geared hub with build in brakes when you pedal backwards
I will need all that goes with it like shifters cables and external gears washers nuts and so on
It must be geared for hills (mountains) not for speed
If you can supply this on a mountain bike wheel rim with tyre and tube complete it will be wonderful the quality mid range
We are Mr Wheelchair in South Africa and are in the process of building a 3 wheel trike for a disabled person he will pedal it by hand like a hand cycle the disabled person we are building the bike for does not have funds we are doing it as a promotion
I will pay by credit card