Hi, I'm trying to figure out something here. Just last week, on a 25F degree night, I left work for my 3 mile commute home. The bike rode fine as usual & I stopped 2 miles along at a store for a few things. After 15 or so minutes I got on the bike again but immediately had this specific problem: the crankset/chain/rearcog spun w/out moving the rear wheel, ie the rear hub.
This didn't happen all at once, the rear wheel would "catch" & then the bike would move. Then, as I rode, the rear wheel/drivetrain problem would happen again & again, until 4 miles along when the rear cog would just spin clockwise or counterclockwise with no effect on the rear hub.
After walking the bike to my apt, and waiting maybe a half-hour, the rear cog started moving the rear hub/wheel once again.
OK....anybody can tell me what happened here? I assume that the internal parts of the rear hub somehow froze so the cogs movement was unaffective, right? Let me know what you think.
Thanks!
ban guzzi
12-12-07, 10:41 PM
grease stiffened up in the rear hub. Started to have this problem on my commute with snow and temps around 10F. I just leave it in a 'good enough' gear and don't stop pedaling. So far so good and I've got a 20 mile round trip.
balto charlie
12-13-07, 06:06 AM
happened to me a few years back. I almost did a face plant when the hub stopped and the crank spun freely. It can really be dangerous. I asked folks here and what was highly recommended was to drop oil "into" the hub. I had an older system, freewheel/hub. I laid the bike on its side, added a few drops of oil to the end of the hub(center of the freewheel) and let it work it's way in. If memory serves I dropped oil because I had an old non repairable hub. It stopped freezing up and lasted another winter.
oneredstar
12-13-07, 06:31 AM
Sounds like the pawls in your freehub froze. This happens when it is cold out and you freewheel, even for a slipt second. The pawls stay down and thus no foreward movement. You can remover the freehub body and change the grease that is inside to a more suitable grease for winter.
ax0n
12-13-07, 08:08 AM
Doug (http://mnbicyclecommuter.blogspot.com/) recommends Morningstar Tools' "freehub soup" lubricant and
freehub buddy (http://www.morningstartools.com/freehub_buddy1.html) injection system to get it into the pawls. I am thinking of trying it out this winter.
meaculpa
12-13-07, 03:22 PM
Thanks. I may need to get some help from some friends but it sounds doable.
jimmibudd
12-14-07, 07:08 AM
hey folks....
i've had the same problem, but only on really cold days....
this year it seems to happen more.... and the further i am from my start point...
i'll second the suggestion to just keep pedalling....
my freehub is also old and non-repariable... i've never heard of the oil suggestion and i plan on trying it...
how much oil do you add?
just a few drops?
did you have to remove the cassette? or just run it down the axel?
thanks for asking/answering such a great question!
jB
ax0n
12-14-07, 07:40 AM
The Freehub Buddy actually lets you inject fresh "freehub soup" or other solvents and lubricants directly into the freehub forcibly, getting the new lubricant into all the nooks and crannies. It works better than just pouring light oil into the body. If I ever experience freeze-up like this, that's the route I'm going.
pluc
12-14-07, 06:01 PM
I've ridden down to -20C this season with my (new from october) Nexus 8R25. My brother's is a Nexus 3 speed and I don't think it has frozen yet. What model are you using?
rocky rode
12-16-07, 10:21 AM
OK....anybody can tell me what happened here? I assume that the internal parts of the rear hub somehow froze so the cogs movement was unaffective, right? Let me know what you think.
Thanks!
As mentioned the lube in your freehub is too thick for the cold. It's easy to fix if you're capable of overhauling your hub. Pull the axle and freehub. Pry off the rubber seal on the spoke side of the free hub and drip in some synthetic motor oil, I use 5-30 wt. in the winter, let it sit a bit and drip in some more. Put the hub back together and you might as well use a thin winter grease for the bearings too. I'm assuming your hub is Shimano? Others may or may not have the rubber seal that you will be able to remove.
I do this to all our bikes and it seems to work just fine in the summer with this oil too. Park tools website can give you instructions on taking your hub apart if you aren't familiar with doing this. Good luck!
DogBoy
12-17-07, 12:10 PM
This happened to me, but only at -5 F. It's rarely that cold, so I don't worry about it. I did have to bring my bike into the reception area for a few minutes to warm it up before heading home. The key is to keep pedaling once it catches. The second you stop pedaling, it will spin freely again.