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Rear wheel won't engage
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03-14-2010, 06:58 PM
After winter storage I tried riding my Mountain Bike. Chain and everything seems fine, sprocket turns, etc. but rear wheel spins freely, not engaged. Bike is a few years old but has had very little use, It worked fine when I put it away.
Any suggestions? Thanks.
03-14-2010, 07:03 PM
Sounds like a freehub or freewheel problem. Here's a couple of similar threads that may help:
http://forums.bicycletutor.com/thread-965.html http://forums.bicycletutor.com/thread-972.html
03-23-2010, 07:44 AM
I have the same problem and have just come on here looking for help!
Please excuse my lack of Avatar and bike pics but I'm at work so don't have any available. I've had a bike for 7 or 8 years and, to my shame, have barely used it. It's a mountain bike as far as I'm aware but has no suspension and weighs about as much as a small family car! It would have been very cheap when new and was given to me by an elderly lady who won it in a raffle. I recently made the decision to start riding it to work and back, mainly to save money but also to get myself fit. I started last week and it was really hard work for someone who hasn't even been on a bike for a few years and I don't really do any other sports. My place of work is approximately 6.5 miles away and there are lots of hills along the way, it was taking me around 40-45 minutes most days. And so to the problem.... I set of to work this morning and peddled up a hill. As I started to roll down the other side of the hill, my chain seemed to be very slack. As soon as I started peddling again, the chain tightened and I carried on. Around ½ a mile later, I tried to pedals to go up a slight hill and my peddles just shot round with no resistance. I fell off the bike in slow motion and luckily, at 5 am, there was nobody about to laugh at me. That was the end of my bike ride. Now if I turn to pedals, the chain moves and it drives the sprockets at the back but that's all, the rear wheel doesn't go around with them. I had to get a colleague to pick me up and when I described the problem to a Maintenance Engineer at work, he gave the highly technical response... "It's fu**ed". Anybody got a more constructive response or any advice to give? Apologies, only just noticed the reply by Alex. I'll check out those threads, thanks.
03-23-2010, 11:03 AM
The pawls inside the freehub (or freewheel) are gunked up (technical term here...). There is a ratchet mechanism that allows for coasting (when it disengages) and engages, when you apply force to the wheel. Try applying some lube to the inside might free this up.
03-23-2010, 11:04 AM
Hi Reprobate,
Check out the the links that Alex shows above. If that does not sound like the problem come back and post.
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
03-24-2010, 06:36 AM
Thanks all. I've just collected my bike from work and will have a look at it over the next few days and let you know.
03-27-2010, 06:25 PM
(03-23-2010, 07:44 AM)Reprobate Wrote: I have the same problem and have just come on here looking for help! Hi. I tried the warm water and it worked. I filled a watering can with warm, not hot, water and poured it over the rear sprocket and hub. It worked right away. I then re-lubed the area. The grease must have been stiff from the cold weather.
03-31-2010, 03:05 PM
I tried the tips suggested but it didn't work in my case. I took my rear wheel to a local repair shop and for just under £16, they fitted a new freewheel within a minute or 2. Obviously I would have preferred not to pay anything but I'll settle for that.
That wasn't the end of my problems though as my left pedal fell off the other day! haha The thread was stripped and being a LH thread, the lads at work couldn't tap it. We forced the pedal back on and so far it has held. These problems, together with the fact that I'm clearly using the wrong sort of bike to commute to work and back, have led me to look at cyclescheme.co.uk and my employer is actually very interested. As long as I can get a few other colleagues to show interest, I should be able to get a £400 -£500 road bike before long, tax free, saving around 41% and paying by weekly wage deduction  If this happens, I'll let you know what I get and add a pic. I'll probably get it from http://www.cyclistdiscount.co.uk/Mens-Bikes-Road-/Racing-Bikes/c8_25/index.html so feel free to have a look and advise me.
03-31-2010, 07:06 PM
Sorry the first did not work out for you. On the other hand you have plenty of spare parts
. Took a look at the current one and yea that is nice choice.
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
03-31-2010, 07:50 PM
Which one? I just linked to the site with a selection of road bikes.
03-31-2010, 09:24 PM
All of them actually
 . Very nice line of bikes to choose from.
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
02-09-2014, 10:00 AM
(03-27-2010, 06:25 PM)billbr Wrote: Hi. I tried the warm water and it worked. I filled a watering can with warm, not hot, water and poured it over the rear sprocket and hub. It worked right away. I then re-lubed the area. The grease must have been stiff from the cold weather.Thank you! Cold Weather! I just had this problem (pedals spinning forwards, cassette spinning, but wheel not moving) today, with a fairly new Mavic wheel freehub, and it was/is a COLD day. (if you look at other threads on various forums https://www.google.co.jp/search?q=%22pedals+don%27t+spin+the+wheels%22 where people are reporting this problem a majority appear to be in winter) I think that my pawls gunked up, and the oil・grease is cold, adding to the gunkyness, so my pawls were not poking back out. I used warm water with washing up liquid in a garden spray gun, brake clear, WD40, and a light oil in that order, and it seems fine now. I blame myself for letting my bike get really dirty, and for using two-stroke oil liberally on my chain and rear cassette. I happened to have run out of light oil. I will stick to the thinner oil in future, so that my pawls do not, stick. (though I note that some recommend two stroke oil http://www.bikeforums.net/archive/index.php/t-695185.html but perhaps the "Quicksilver" that they recommend does not thicken up at low temperatures. Yes, that sound likely since it is a marine 2 stroke.) It is pretty scary though, since one of the times I have come off my bike was when the pedals span freely. I stamped on my expecting pedal resistance on a downhill, and I was in my lowest gear, and so the pedal was like falling through air, and this unexpected lack of resistance caused me to unbalance and fall off (note to self, check that you are not in a low gear on downhills). If this sticky pawl problem were to come on suddenly in traffic, and my pedals were to suddenly spin freely, it could be the death of me. Lots of washing, lots of light lube.
02-10-2014, 12:11 PM
Well, how new is "fairly new" for the rear hub? In my experience the (road) rear hubs need the freewheeling mechanism serviced once a year. Check Mavic's repair docs, it is actually really easy. The only special tool you need is a cassette tool and a chain whip. You will also need a box wrench (I think 17mm) and an Allen key (10mm?).
02-10-2014, 01:27 PM
(02-10-2014, 12:11 PM)Joe_W Wrote: Well, how new is "fairly new" for the rear hub? In my experience the (road) rear hubs need the freewheeling mechanism serviced once a year. Check Mavic's repair docs, it is actually really easy. The only special tool you need is a cassette tool and a chain whip. You will also need a box wrench (I think 17mm) and an Allen key (10mm?).Thank You. My Mavik rear wheel is only 8 months old so I blame my lack of maintenance and the use of cheap two stroke oil in really cold weather. There are other problems with mavic free hubs but this was just cold weather and cheap oil, imho.
02-11-2014, 05:40 AM
No, you are right, I need to service my hub. It happened again, in traffic. I bet it is really gunked up in there. I need to buy a chain whip.
02-11-2014, 07:52 AM
I need to overhaul my road bike's freehub every year. What usually happens is that once the temperatures decrease the pawls no longer disengage correctly and the cassette is spun forward when coasting (downhill, fast, very high gear). Then the chain becomes slack and rubs on the tyre, making an awful racket. After the ride I tear apart the hub, clean everything and use a light oil (only one drop) on each pawl.
It is all covered in Mavic's tech docs. Oh, thinking about it: Maybe you do not need to remove the cassette, I like doing it anyway to clean it. On the other hand, a chain whip is not one of the expensive tools and it is a good one to have, as is the cassette tool.
02-16-2014, 12:40 AM
Agree completely with Joe_W, similar experiences. I just do not have the special tools to open the hub. Tried the warm water fix - did not work. So I decided to spice things up a little and used a small blow torch to heat the hub. Worked great! Clean and fast, no dis-assembly required. I fixed two hubs in 5 min.
02-16-2014, 03:46 AM
Warm water and heat do nothing to change the state of the gunk inside, so it just sets the stage for a repeat. The proper fix is to flush out the mechanism with solvent, then lubricate with a medium weight oil flowed inside, so that both the pawls and bearings are lubricated. I will admit I don't have much experience with winter riding on a cassette equipped bike but in years of winter riding on a freewheel bike I never experienced a freewheel problem.
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