Bicycle TutorBicycle Tutor

Show off your bike!

Related video tutorials:
Wobbling freewheel
#1
Hi!

I recently got a cheapie old mountain bike. A few minor thing had to be done to it to get it into a good usable condition. The old thing thats still up with it is a slight wobble in the rear freewheel. It makes the rear gears slip a bit.

I don't know much about freewheel mechanisms... is there user serviceable bearing in then or is replacing that the only option?

i've uploaded a video to show the extent of the wobbling
http://www.youtube.com/watch?v=7nMAkJvDnBI

So if anyone has suggestions about repairing it or even what the actual problem is that'd be great


Thanks!
Reply
#2
Possibly a bent axle? No way off really telling without stripping it out.
[font=Trebuchet MS]Ride hard or ride home alone![/font]
Reply
#3
Great Job posting and taking the video. I should learn to do that.

AS per wobbling freewheel, like cycler UK said got to dissemble and look. Make sure everything is tight first especially the nuts and cup in the gear cluster. See if the cluster has play and moves side to side. If tight than dig deeper.
The wheel is spinning straight, so the problem seems to be in the cassette/freewheel gear mounting or inner bearing damage in the freewheel.

FYI on freewheel the whole cluster screws onto the hub, in a cassette the cluster slides onto a slotted mount.
Never Give Up!!!
Reply
#4
It's rare you can do much to service a freewheel or at least it's rarely worth it because replacements are cheap. I'm pretty sure this is a "freewheel" because it has 6 speeds and there is no flare on the hub inside the flange like a cassette hub usually has. I doubt a bent axle would cause this since the freewheel doesn't ride on the axle and the axle is not rotating.

I also question whether the freewheel wobble itself is the cause of your gears "skipping". It would normally only cause problems if it wobble so much that the chain hits the teeth of the next cog. That said, the ratchet in the freewheel might be worn also which can make the chain slip. When you say skipping, is it jumping between gears or is the chain "letting go" and then re-catching when you put a lot of pressure on it?

If it's not a shifter adjustment issue, you probably should go ahead and get a new freewheel and chain.
Reply
#5
Yes I agree with Dave that it is a freewheel. Had one similar to this that had a bent axle. If it is a cheapie MTB then you will have a MAJOR chance of the axle being bent. Quick way around this if you really want to fix it up is to find another piece of junk mtb rear wheel take out the axle and using a ruler and micrometer check its axle against the one you have. If it is the same length and radius just put it in place of the bent one Wink .
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
Reply
#6
Your case is quite pronounced... I have never seen a cluster that does not wobble to some degree--including my Ultegra and Dura Ace cassette-based systems.
Reply
#7
A fairly common problem on cheap bikes, may be the fw itself, the thread on the hub, etc. as all the components are as cheap as they can be, and once you start getting into replacement, if the teeth on the chainwheel and the chain itself are worn then you end up replacing the lot.

The skipping gears have probably another cause, is the changer out of alignment, or a stiff link in the chain.
I suggest you have a ride to your local bike shop and get advice off them.
Reply
#8
I recently had a freewheel that had just about as much movement and it it had no effect on gear changing or any skipping. I would suspect a worn chain or sprocket teeth...
Reply
#9
it look like the wheel did wobble a little so I would true the wheel first. And then check the axle out.
My dad always told me a Sledge a matic can fix any thing.
Reply
#10
Hi all,
Thanks for all the replies!

I partly guessed that it was due to cheap/worn bike parts. I might try and align the rear deraileur before i go taking the bike apart. I do have a 6 sprocket cassette somewhere so might just get a freehub wheel and a new chain if adjusting the deraileur doesn't work. with the weekend ahead i'll hopefully get some work done on it and get it sorted. I did align the front gears when i got the bike but though something had to be done to the back so didn't bother.
Reply
#11
I spent the evening with my bike and there been some improvement to the chain slipping.

The rear derailleur hanger had been bashed at some stage and was out of line. did some gentle coaxing it back along with tuning up the front and back gears. definitely doing less slipping now - The chain still doesn't seem to fit into the rear sprocket set properly. possible that a different rear wheel was put onto an old chain or something.

The freewheel still wobbles, didn't have the tools at home to take the wheel apart so it still needs repair or replacing. theres a local bike workshop happening in the near future so hopefully get the bike sorted properly there
cheers for the suggestions

brittney
Reply
#12
my rear wheel problems flared up again this weekend so i finally dismantled the wheel to have a look. problem was a badly worn bearing cone

took some pics in case anyone interested

this is the worn side of the cone
[Image: 25sy3br.jpg]

this is the ok side
[Image: 3517h52.jpg]

hopefully a new one will will sort it out

the freewheel sounds a bit noisy when moving it (like theres something rattling around inside it) so prob'll change that too if i can get a cheap one
Reply
#13
While you are at it get some new bearings for both sides. If you have the extra money I would replace the other cone nut as well.
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
Reply
#14
Hi brittney, thanks for posting a feedback about your problem. My bike has the same freewheel problem. Now I know where to start from.. cheers
Reply
#15
(05-10-2010, 05:07 PM)DaveM Wrote:  It's rare you can do much to service a freewheel or at least it's rarely worth it because replacements are cheap. I'm pretty sure this is a "freewheel" because it has 6 speeds and there is no flare on the hub inside the flange like a cassette hub usually has. I doubt a bent axle would cause this since the freewheel doesn't ride on the axle and the axle is not rotating.

I also question whether the freewheel wobble itself is the cause of your gears "skipping". It would normally only cause problems if it wobble so much that the chain hits the teeth of the next cog. That said, the ratchet in the freewheel might be worn also which can make the chain slip. When you say skipping, is it jumping between gears or is the chain "letting go" and then re-catching when you put a lot of pressure on it?

If it's not a shifter adjustment issue, you probably should go ahead and get a new freewheel and chain.

Yeah, maybe the skipping is caused by the wobbling of the hub. I got the same problem as that guy and I went to a few of my local bike shop and asked if they can help me find the problem.
I got a cheap 6 speed bike and the the 5th and 6th speed is skipping sometimes and the 2nd gear is just too noisy! The mechanic got my rear derailure screws right but the problem wont go away. So, the mechanic concluded that the problem is my hub and maybe it's causing the skipping.
Maybe I need to get it fixed... Sad
Reply
#16
My freewheel is doing this too. I think it's because the bearing cup is damaged, I hadn't been maintaing my bike properly, and a few weeks ago while I was riding the wheel started getting tighter and tighter until it completly froze up and wouldn't turn at all. I guess the cone on the drive side got threaded into the bearings while I was pedaling.
When I took it apart, I found the drive side bearing cup was bent, and there was a small crack in it.
I was able to re- pack the bearings, and it's rideable now, but I can' t get a good adjustment of the bearings, and it wobbles a bit, just like in your video. The chain doesn't skip though.
Reply
#17
The freewheel is wobbling for two reasons: The right-left movement is because the threads for the freewheel are not exactly centered on the axle. The up and down is because the threads are not at exactly a right angle to the axle. In my experience yours is not wobbling enough to have an effect on shifting or skipping. Almost ALL freewheels wobble, and it's seldom the cause of any problem.
Reply


Possibly Related Threads...
Thread Author Replies Views Last Post
  Need HELP with my hub and wobbling freewheel! NewbieRider 3 3,761 07-09-2014, 03:18 AM
Last Post: cny-man
  Wobbling back wheel luke8885 1 3,552 08-18-2012, 08:47 PM
Last Post: nfmisso
  Wobbling rear wheel - not caused by spokes roscoe 2 10,885 09-07-2008, 11:13 AM
Last Post: roscoe

Forum Jump:



ISSN 1918-3445 © Copyright 2007-2010 Bicycle Tutor / Privacy Policy / Created by Alex Ramon

feed