Working through some maintenance challenges and mystery noises with my bike (GT Grade, Shimano 105 drivetrain). I think it might be related to my freehub.
Here's a video of how much spin I can when I manually move the freehub...not much at all. Can I have a reality check -- how much spin should I expect? Note, when the wheel is mounted it spins well.
Eh, maybe a bit more than that. But I wouldn't worry about the free spin duration, though. It's a useless measurement, since you only use the feature when you are already going faster than you want to pedal. You should be more concerned on how smoothly the freehub spins as that indicates whether the bearings are contaminated or broken. Remove the cassette and spin the freehub with your fingers. Is it sticky or do you feel roughness beyond the pawls clicking? You might not be able to feel it with the cassette on, as it's weight can dampen the vibrations.
The Freehub is locked in step with the hub when you're pedalling, so there are zero mechancial and friction losses in that component while you're providing power.
That freehub clearly has more than usual friction in it, BUT that only comes into play when you're coasting, or walking the bike.
I would take the cassette off, protect the brake rotor, and clean the whole freehub area. Compare a before-vs-after level of twist needed to move the bare freehub with your fingers.
I probably wouldn't, but if you choose to open the freehub for a deep clean, be aware there may be a hundred tiny bearing balls loose inside. Clean it, dry it, lubricate it, and reassemble.
