This is on Jr's single-speed. It's been really cold here (-31 C overnight) and when he dropped over this morning he complained of the the crank spinning with chain rotating but intermittent forward movement.
My wife and I rode our fat bikes to church and back (round trip c. 10 km) without incident, before tackling the malfunctioning bike. Pedaling effort for our ride was high though - riding into thick air, tires soft, thick grease in the bearings ...
Jr's big brother (our oldest son, not an Orwellian sort) and family were over for lunch and I ran this past him - he's a much better bike mechanic than I am. He immediately diagnosed the problem as a frozen freehub. He'd encountered this a few years ago and had poured hot coffee over the hub to warm it up enough to function. (This was successful.)
I removed the rear wheel on Jr's bike and brought it into the house. (The garage was at -10 C - no fun for working on bikes.)
Removed the freehub and soaked it in PP 5W-30. (Wanting to standardize, I switched over to Mobil 1 exclusively a few years ago. I think the PP is just as good, but someone always seems to have M1 on sale, so I've got this spare jug for general-purpose use.) Reinstalled the freehub, and I think all's well. The oil would have thinned any thick grease, and displaced any water.
I guess this is not as unusual as I'd thought - I've just been lucky to not experience it myself. That may be in part to our garage never getting really really cold.
https://forums.mtbr.com/commuting/freewheel-fail-cold-942737.html
My wife and I rode our fat bikes to church and back (round trip c. 10 km) without incident, before tackling the malfunctioning bike. Pedaling effort for our ride was high though - riding into thick air, tires soft, thick grease in the bearings ...
Jr's big brother (our oldest son, not an Orwellian sort) and family were over for lunch and I ran this past him - he's a much better bike mechanic than I am. He immediately diagnosed the problem as a frozen freehub. He'd encountered this a few years ago and had poured hot coffee over the hub to warm it up enough to function. (This was successful.)
I removed the rear wheel on Jr's bike and brought it into the house. (The garage was at -10 C - no fun for working on bikes.)
Removed the freehub and soaked it in PP 5W-30. (Wanting to standardize, I switched over to Mobil 1 exclusively a few years ago. I think the PP is just as good, but someone always seems to have M1 on sale, so I've got this spare jug for general-purpose use.) Reinstalled the freehub, and I think all's well. The oil would have thinned any thick grease, and displaced any water.
I guess this is not as unusual as I'd thought - I've just been lucky to not experience it myself. That may be in part to our garage never getting really really cold.
https://forums.mtbr.com/commuting/freewheel-fail-cold-942737.html