What is that noise?

June 8, 2007 9:52 AM

Bicyclefilter: A pronounced grinding/scraping from my rear wheel. Is this potentially unsafe, or simply embarrassing, to ride?

When I say pronounced, I mean passersby chuckle. The wheel sounds really old, really sad and really grumpy. When I spin the wheel freely, the gears wobble a bit, leading me to think the threads on the gears or the axle are close to stripped (?? I can still pedal just fine, so I don't know).

What's the worst that can happen, realistically? The wheel falls apart? Or I just suddenly find I'm pedalling but not moving?

posted by poweredbybeard to sports, hobbies, & recreation (7 comments total)

Oh and if it's relevant, the wheel seriously needs to be trued. (It's a shit bike on life support, and I have no time to attend to it for a couple of days)
posted by poweredbybeard at 9:53 AM on June 8, 2007

Probably the hub bearings are shot. It may grind on like that for a while but it is time for either new bearings or a new hub. Usually the bearings are quite easy to replace but if they are really gnarly they may have destroyed the bearing races too.

Worst that can happen is not much really.

Check the nuts that hold the wheel on for tightness. If they're tight, you're probably completely OK until the wheel stops turning round.
posted by unSane at 10:21 AM on June 8, 2007

Yeah, i'm going with the hub bearing diagnosis too.

But you'd be surprised how cheap bicycle services are at your local bike shop. I just had a bottom bracket (the bearing set that the pedals turn in) rebuilt on my old Schwinn for less than $25.00.

Don't put a DNR on 'er yet!
posted by M.C. Lo-Carb! at 10:42 AM on June 8, 2007

Could also be the freewheel. If it does it pedaling or not, then it is the hub. If it only does it when you coast then it is the freewheel.

Eventually it will just lock up, either way. Freewheel lockup = always pedaling. Hub lockup = no moving, bike carried on shoulder to destination.
posted by Big_B at 1:22 PM on June 8, 2007

a seriously dry chain will always always make awful noises, especially going through a derailleur (which i assume you have - it's the device that changes gears, physically moving the chain from one cog to another).

www.sheldonbrown.com and www.parktool.com are good resources.
posted by entropone at 1:54 PM on June 8, 2007

Don't fix it. You might be riding a genuine scraper bike!
posted by nakedsushi at 4:04 PM on June 8, 2007

just do it yourself, it is easy to fix. open the wheel and replace the bearings, will cost you less than $10
posted by edtut at 9:33 PM on June 8, 2007