bike freewheel disabled by the cold

Joined
Jul 7, 2014
Messages
5,133
Location
Winnipeg MB CA
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
 
Yep, the grease used in freewheels and freehub bodies are going to have their limits with both high and low temperatures. It's generally not very thick but over time it can separate as well leaving behind a thicker paste. Motor oil has the downside of a lot of detergents that standard grease won't have so when things warm up, don't be surprised if a lot of black oil comes out of it. Won't really harm anything but might make a mess.
 
Very few ride in these low temps, therefore some bike parts isn't designed for it. I've seen them frozen before also. I leave my bike inside so don't have a problem when I head out on 10 degree days.
 
Originally Posted by Eric Smith
Very few ride in these low temps, therefore some bike parts isn't designed for it. I've seen them frozen before also. I leave my bike inside so don't have a problem when I head out on 10 degree days.

Agreed, which is probably why our bikes (my wife's and mine) are OK - they warm up in the garage, which is not too far below freezing most of the winter. Our son's bike likes outside except when he's visiting here, and it's been pretty cold for a few days now.
 
Man. I have a hard time getting my wife to go outside and get in the car in -10 let alone ride a fat bike to church. Hats off to you and your wife.

I lube my freehubs with Phil Wood Tenacious Oil. I've had zero issues in any temp.
 
There is a huge difference in lubricant viscosity once you start going below about -10C, and the difference between each additional -10C is pretty huge. Stiff at -32 sounds like it was expected to be used no cooler than -15C or so., and even then only after it's been run (which effectively warms up the lubricant). or goes out after warm storage indoors.
 
Originally Posted by NYEngineer
Man. I have a hard time getting my wife to go outside and get in the car in -10 let alone ride a fat bike to church. Hats off to you and your wife.

I lube my freehubs with Phil Wood Tenacious Oil. I've had zero issues in any temp.

Originally Posted by Virtus_Probi
I am impressed as heck that the OPer and his wife bike to church in the winter in Winnipeg! Well done!

NYE, for what it's worth, I find it far worse getting into a cold car parked outside than bundling up and hopping on the bike. I bought my fat bike in the summer of 2015, and started using it in November when the snow fell. My wife borrowed it to try it out, and absolutely loved it. At that point I needed to get her a bike of her own. She's gotten a lot of use out of hers over the last three years. I've heard good things about Phil Wood oil - I'll have to check it out. Do you take the freehub apart to lube it, or is the oil thin enough to immerse the hub in?

VP. when I used to arrive at work on foot or on bike on a cold winter day, invariably a coworker would ask why I didn't drive to work. I'd respond something like "Well, this morning I was probably a lot happier to arrive at work than you were."

If you're dressed for it, it's not bad at all. With the studded tires we feel pretty secure. By the time you warm up a car, drive, and find parking at the other end, the bike is not that slow by comparison. When I was riding to work, I would typically pass coworkers stuck in traffic (I was on a parallel trail) and get to work before they did.
 
The Tenacious oil is very sticky and sorta thick. I can't imagine it doing much seeping. All of my bikes have either Hope or Bike Hub Store (Bitex) hubs. The drivers come off relatively easily so no big deal cleaning and lubing them.

Probably a bit more work on Shimano and most other factory hubs.
 
Freehubs and freewheels have different seals, depending made where and when. Some have sealed bearings so no oil going by them ... I usually flip the bike up sideways on two saw horses and dribble oil into the freehub/wheel from the chain side while I spin the chain slowly. As soon as I see it running out dark and dirty onto the wheel hub or the off-side, I know I'm done for the winter. In the spring I dissemble and grease with Park Tool wheel bearing grease.

Gotta keep water out if possible ... Freezing water can do more damage than just keeping the pawls away from the hub ...
 
Last edited:
In case of a Shimano freehub....


Lube with light non sticky oil a.k.a ATF
wink.gif
 
Thanks all for your input. KameleON, that's a very good video - thanks for posting! That's very similar to what I did, although I did not remove the seal and work in grease. Rather, I submerged the freehub assembly in motor oil. Jr says it's working perfectly now.

Still no problems with our fat bikes - I wonder if they're factory-equipped with a special winter lube? (It was another cold one today, close to -30 C this morning. The bike was good though.)
 
Originally Posted by Kamele0N
btw.....that Phils tenacious oil looks like a chainsaw bar oil.....so
wink.gif



Bar & chain oil seems to have something in it that makes it form long strings of oil between the chain and chainrings, cogs, and derailleur jockey and tension wheels. Phil Woods Tenacious doesn't do that. Otherwise, they seem very similar.

As far as lubing freehub pawls go I've always heard to use a light coating of lightweight grease to prevent the pawls sticking at low temperatures and failing to engage. I've used bar & chain oil with good results. I'd imagine, if you're using the bike in winter, a synthetic lubricant would be a good choice as it shouldn't thicken as much in the cold.
 
Yes something like ATF...on one cycling forum I once red that even Shimano oil for their disc brakes is ok...and it is basically very thin hydraulic oil...
 
There might be a bike shop in Winnipeg that has something of use in the cold. I don't know how much winter riding there is at the university there. In Saskatoon, they bike on campus no matter how cold it is, and in droves. In Regina, on campus, the only bikes you see on campus in the winter are those that were abandoned in the fall when someone got stranded there in the first snowfall of the season.
wink.gif
 
Originally Posted by Kamele0N
btw.....that Phils tenacious oil looks like a chainsaw bar oil.....so
wink.gif


Rumor has it that the latest iteration of Phil's Grease is AeroShell 33 or Mobilgrease 33, both are Boeing-approved grease. Phil Wood is tight-lipped about this.

There used to be a tool to flush out a Shimano freehub, the maker of that tool died a while ago. I've had luck with a WD-40 flush and Penetro 90 afterwards. I think even MaxLife ATF/Dex VI/Merc LV/Toyota WS will also work.
 
Back
Top