Pedals not turning the wheels. Help needed!

[Kumquat]

Please explain things in very simple terms as I know next to nothing about bike mechanics. I can tighten my brakes, change a tire and index my gears by following a youtube video step by step and that's it

Over the last couple of days when I was cycling I occasionally felt something "slip" and suddenly the pedals can turn with no resistance, but then within a second it "catches" again and I can continue cycling with no mishap.

Cycling back from church this morning the problem is now much worse, because instead of immediately catching back on it takes several seconds and I need to get off the bike because with the lack of forward motion I would otherwise fall off! It's also happening much more frequently, to the point where I gave up and walked the rest of the way home. I can't see anything OBVIOUSLY amiss when I look at the bike. I don't really know what I'm looking for, but the chain in still on the derailleur etc.

LBS is shut today because it's sunday, and I leave for work before it opens and returns once it is shut, so the next opportunity is saturday... My bike is my only source of transport and I don't really fancy waking up an hour earlier to walk to work in the cold! Is there anything I can do to fix/temporarily improve the problem?

 

[Spiderweb]

Sounds like the freehub pawls are not engaging. I had a similar intermittent problem last year, I took it to my LBS and they replaced the freehub. I paid £24.99 for a new Shimano freehub plus labour.

 

[dfthe1]

Sounds like your free hub. Have a look here: https://www.cyclechat.net/threads/odd-gearing-to-issue.213307/#post-4677422

 

[HLaB]

It could be the pawl springs inside the hub not engaging because either they are bunged up or broken. If its the latter you can't fix it that I know off until you get the part. If its bunged up causing sticky pawls you may be able to take apart the hub and clean them, there's usually videos on you tube that show you how to.

 

[Fab Foodie]

Basically, the Rear wheel where the cogs are attached has a ratchet system that engages when oedalling wnd allows the wheel to spin when not. It's a very simple lightly sprung system. However eventually the lubrication goes and the pawls of the ratchet no longer move freely to engage with the wheel when you start pedalling.
It's generally not terminal, but some stripping down might be required.
The first question is whether it's a freewheel or freehub. Some details about bike and wheel will help!

Cheers
FF

 

[Kumquat]

The bike is a Carrera Crixus (halfords special but it's been pretty good actually- I live in a high crime city and can't afford anything fancy anyway) Here is a link to the spec http://www.halfords.com/cycling/bikes/road-bikes/carrera-crixus-limited-edition-cyclocross-bike-2015

Don't know anything about whether it's a freewheel or freehub sorry.

 

[dfthe1]

The bike is a Carrera Crixus (halfords special but it's been pretty good actually- I live in a high crime city and can't afford anything fancy anyway) Here is a link to the spec http://www.halfords.com/cycling/bikes/road-bikes/carrera-crixus-limited-edition-cyclocross-bike-2015

Don't know anything about whether it's a freewheel or freehub sorry.

I have exactly the same problem with the same bike. It's a free hub. Need to get my chain whip out and find out what type now so I can replace it!

My problem has been intermittent and a good hard drop on the rear wheel has sorted it quickly.

 

[Kumquat]

Ok, I have watched this video which was very helpful
View: https://www.youtube.com/watch?v=IDwH0QOnn_Y

But how do I take the cassette off the rear wheel to get at the freehub to clean it?

 

[dfthe1]

Ok, I have watched this video which was very helpful
View: https://www.youtube.com/watch?v=IDwH0QOnn_Y

But how do I take the cassette off the rear wheel to get at the freehub to clean it?

You'll a couple of special tools -- a chain whip and a cassette spline tool. Lots of videos showing you what to do.

 

[Fab Foodie]

Ok, I have watched this video which was very helpful
View: https://www.youtube.com/watch?v=IDwH0QOnn_Y

But how do I take the cassette off the rear wheel to get at the freehub to clean it?

You need a 'chain whip' and the appropriate cassette removal socket and large adjustable spanner. All available from Halfords or Decathlon.
To get at the freehub gubbins you may also need cone spanners.

 

[dfthe1]

I suspect it will be a fairly rubbish no-brand in a there so I plan on replacing with something decent. Let me know how you get on though.

 

[MichaelW2]

The rear sprockets (cogs) are held onto the freewheel with a locknut that has a castelated or spline pattern. You need a casette tool with the right pattern of splines to slot between locknut and axle, a large wrench to hold the tool, and a chain whip to stop the freehub rotating as you undo the lockring.
Alternatively you can get small cassstte tools such as NBT2 which can be used on the bike but these dont work if the locknut is very tight.

 

[Kumquat]

If I have shimano gears is it likely to be more complicated like this
View: https://www.youtube.com/watch?v=90XxoPHWbI4
? If that's the case then I may as well wait until next weekend and get the bike shop to do it. If it's as easy as the first video I can beg some tools of some friends and do it myself

 

[HLaB]

Ok, I have watched this video which was very helpful
View: https://www.youtube.com/watch?v=IDwH0QOnn_Y

But how do I take the cassette off the rear wheel to get at the freehub to clean it?

You'll need to remove the cassette, a chain whip, a lock ring tool and depending on the type of latter a adjustable spanner.

My free hub bodies are all that type and you just need a hex key and the adjustable spanner to remove it but some wheels need two cone spanners.

 

[oldwheels]

In emergency as a possible short term fix. Lay the bike on it's side with sprockets downwards. Squirt WD40 into the freewheel and spin the wheel. This avoids getting the WD40 into the hub bearings and may free up the pawls in the freewheel. It worked once for me anyway.