The freewheel is a ratcheting mechanism, that coupled with a set of gears, is that threaded onto the rear hub of a bike. The freewheel allows the rear wheel to engage and move when the pedals are spun forward, but coast freely when the pedals are stationary or spun backwards.

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26
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2answers
7k views

Why does pedalling backwards not move my bike backwards?

On the BMX bike I have, pedaling backwards moves the chain but doesn't drive the wheels of the bike backwards like you would expect it to. Why is this?
19
votes
7answers
30k views

Why are higher-end freewheels so much louder when coasting?

I tend to ride relatively modest gear (Tiagra/Ultegra), but when I'm riding near higher-end bikes, I sometimes notice that the clicking sound that comes from their cassette/free-wheel while coasting ...
8
votes
4answers
4k views

Do silent freewheels exist?

I have only just noticed that my bike dosen't seem to make a lot of noise when free wheeling, in fact it's pretty much silent. Is this down to the fact that I have been putting off a major clean?, is ...
8
votes
4answers
621 views

What can I do to keep my rear derailler in good condition when commuting in the snow?

In the winter, it seems that whatever I do, my rear derailleur stops functioning after few weeks of commuting in light snow. Ice always gets in there somehow, and the chain refuses to move the wheel, ...
8
votes
1answer
234 views

Why do deraillers require a freewheel?

I've seen fixies with internal hubs, but a non-freewheeling rear wheel with deraillers seems to be unrepresented: | Freewheel? | Derailler? | Yes | No | ...
8
votes
1answer
1k views

When to replace wheel bearings

I just ripped apart my mom's mountain bike's rear hub. One of the bearings was incredibly rough, so I replaced it, and the other one was smooth, but didn't turn very easily. Since I didn't have a ...
7
votes
4answers
519 views

What's the point in a freewheel/cassette with incrementally sized rings?

Pictured is a freewheel with 15, 16, 17, 18, 19, and 20 tooth sprockets. What I don't understand is why such small increments are worthwhile. Surely the point of having gears is the variance that they ...
6
votes
5answers
16k views

What should I use to lubricate a freehub?

I've noticed my freehub has gotten quite a bit louder over the last few months. Several people have recommended that I lubricate the freewheel by tipping the bike on its side and dripping lubricant ...
6
votes
3answers
294 views

Are all ready-made wheels sold “cassette compatible” only?

I will have to change my wheels on my old trusty late-80s Peugeot (PS28) soon. The rear wheel is mounted with a freewheel-type 6-speed hub (not cassette). I was wondering if all ready-made wheels ...
5
votes
9answers
8k views

Is there such thing as a freewheel that doesn't click?

The clicking sound of the freewheel on my singlespeed when it's coasting is annoying for me, so I flipped over my back wheel and rode fixed for a few months in blissful silence. But having to pedal ...
5
votes
1answer
2k views

How can I tell if my bike has a freewheel or a cassette?

I bought a Frankenbike off Craigslist. It's a Specialized Rockhopper of unknown year, converted to a commuter, with shocks up front and V-brakes. I love this weird little bike and want to put a ...
5
votes
3answers
446 views

Shaky Freewheel

I posted a question some time ago about vibrations in the frame of my road bike (a 1973 Sekine). Recently, I determined that the rear wheel is sliding back and forth across the axle, with about 0.5cm ...
5
votes
3answers
15k views

Advantages / disadvantages of freecoaster and cassette hubs

I've been reading a lot over the past few days about BMX, and last night I watched a few videos like this one. I have been seeing the words "freecoaster" and "cassette" around a lot, and I was curious ...
5
votes
0answers
65 views

Is changing wheel necessary if freewheel hub with a different speed then previous is attached?

Approx. 3 weeks ago I have found an abandoned frame (including steering wheel, fork, brakes, pedals and shifting gears attached to it). I decided to use it to build a new bicycle since only recently ...
4
votes
1answer
3k views

How do I clean the inside of a freehub?

I didn't know any better and I let degreaser drip into the freewheel body of my Shimano FH-RM65. Now it makes a terrible retching noise when it rotates. How do I clean the inside of this thing? ...
4
votes
2answers
2k views

Mounting a 7-Speed Cassette on an 8/9 speed hub

I asked an earlier question regarding putting modern road wheels on my old steel frame. After clarifying a few things the main issue to me is the number of gears on the freehub. (The freehub I'm ...
4
votes
2answers
2k views

Tightening rear quick release stops rear wheel

I have a medium sized Trek Mountain Track/Antelope with a seven speed freewheel. When I tighten the rear quick release, I have to carefully back off on the tightness so that the wheel will actually ...
4
votes
1answer
1k views

5 speed cassette on 8 speed hub

I just picked up a cheap wheelset to replace the wheels on a vintage bike. The old bike had a 5 speed freewheel (I think. The model printed on it is shimano-ug). The new rear hub is a shimano fh-rm30 ...
4
votes
1answer
708 views

Should cassette “wiggle”

Recently My freehub broke and so I removed the cassette to replace the freehub and noticed, whilst off the bike, 4 of the remaining bolted together 8 sprockets wiggled (4 wiggled together but ...
4
votes
2answers
5k views

How to take apart this rear BMX hub?

As shown in the photo, what tool do I need to take this rear hub apart? I assume I need a tool which will fit in the 4 notches. The problem I am trying to fix is that if you pedal, the rear cog spins ...
4
votes
1answer
406 views

Is it a good idea to switch to hub gear?

I have a Firefox Roadrunner Pro. I wanted to know if it was a good idea to install an internal hub gear on it. I want to install it to reduce dust accumulation and oiling and to simplify the ...
4
votes
1answer
3k views

How many freewheel thread sizes are there?

I'm buying new freewheel and noticed that not every freewheel can be screwed onto my hub because they have different thread sizes. For example: I've found the following thread size specifications: ...
4
votes
4answers
2k views

Why is my chain riding up and skipping teeth on the freewheel?

Due to a number of reasons, I would like to keep my freewheel at all costs (It's a Sachs freewheel, the bike has all sorts of more 'vintage' components, and they're hard to come by). From reading all ...
4
votes
1answer
2k views

How many ball bearings inside shimano MF-HG20 freewheel top and bottom?

help me fix the bearings in my freewheel. I need to know the number of ball bearings top and bottom in my shimano mf-hg20 freewheel, and what size are they?
3
votes
2answers
4k views

What do I need to know when replacing my cassette?

I'm looking to replace the cassette on my bike with a smaller version, as I find I'm only ever using the top ring of my chainring (except once recently during rain-ageddon). What do I need to know ...
3
votes
3answers
2k views

Rear index shifting not staying in middle gears

I have replaced a chain (SRAM PC 830) and 7 speed freewheel (Shimano MF-HG37) on the back of my daily commuter bike about 300 miles/ 3 weeks ago with the same models. The old parts lasted me 4000 ...
3
votes
2answers
38k views

When I pedal the rear wheel is not turning

I have a very old bike. It used to work perfectly, but just recently it happened that when I pedal the rear wheel is not turning. Just for notice I pedal in the correct direction, brakes are not ...
3
votes
1answer
78 views

Freewheel not engaging when temperature below about -20c/-4f. What is freezing?

Is it moisture/slush in the freewheel that is not evaporating because I have to keep the bike outside all winter? Then it might freeze when the temperature goes low enough. How long would it take to ...
3
votes
4answers
124 views

Tyre rubbing against Frame

I'm new here and signed up to seek help. Bicycle : Fixie, it came with fixed gear and freewheel, I use the freewheel cog. Today, after a tire and tube replacement it now rubs on the frame. The new ...
3
votes
1answer
329 views

Can we turn a fixie bike into a freewheeler?

I'm new to the fixie world. I'm planning to buy a fixie bike though, but to start right away would be difficult especially when I'm pedaling down hill. Is it possible to change the fixie bike into the ...
3
votes
3answers
13k views

What tool is needed to remove a Shimano HG-50 freewheel?

What tool is needed to remove a Shimano HG-50 freewheel from the wheel hub? It looks like a 12mm or 13mm Allen key. Will this do it or is there some detail I have missed?
3
votes
2answers
139 views

Reverse Gear in Bicycles

For an ordinary bicycle (neither fixed gear nor capable of changing any gears). Is it possible to modify it to have a reverse gear on it? (i.e. reverse pedaling causes the bicycle to go backward) ...
3
votes
3answers
1k views

Chain skipping on new freewheel and chain setup - What went wrong?

BACKGROUND NOTE: The bike is a 1992 Univega MTB that originally came with 6-speed SIS with a triple chainring. I removed the SIS shifter when it broke, and went with a friction shifter. The bike is ...
3
votes
2answers
172 views

How does this hub come apart?

Really, I have two questions. But first, I see no place to put a wrench on this hub. Well, there is one small notch on one side on the dust cap (on the other side). How do I get this hub apart? It's ...
3
votes
2answers
6k views

How should I lubricate my Shimano freewheel?

I have a Shimano freewheel (MX-30) that came with my bike from new. Unfortunately the internals got all gunked up and it stopped working (never engaged and became free both ways). I have bought and ...
3
votes
2answers
13k views

How did my rear freewheel become incredibly tight overnight?

I got a flat yesterday morning after a normal ride, walked my bike inside the house and propped it upside-down (like this) overnight. This morning, I changed the flat and put on some brand new tires ...
3
votes
2answers
7k views

Options for replacing a 7 speed Shimano cassette / chain

I would like to replace my 7 speed HG70 cassette and chain. My problem is that it is increasingly difficult to find quality parts for 7 speed system. My bike is a Trek 970 from 1993, originally with ...
3
votes
2answers
164 views

Old freewheel removal

I have an old rear wheel - I think its from a Raleigh Arena roadbike from the late 70s or early 80s. There are broken spokes that require the sprockets removed to access. I've done this plenty of ...
3
votes
1answer
205 views

Freewheel sprocket locking up

I was just out riding my bike. Its nothing fancy, just a €300 single-speed with with a flip-flop hub. I usually ride the freewheel side. Today it made some weird noises and decided to lock up / be a ...
3
votes
3answers
285 views

What causes frames to break at the (rear) dropouts?

The drive-side dropout and rear axle have broken twice. It's an old-style freewheel, not a freehub+cassette. (I weigh around 100kg, and ride a lot, and have been touring on hilly, gravel roads, with ...
2
votes
1answer
72 views

What is this cogset body?

I have some backlash (free movement) in my body of cogset, so I try to dissemble my cogset to discover this weird body: I'm trying to find a new one but I don't know how to call it. Any idea how ...
2
votes
4answers
155 views

Direction of chain whip

Is there an easy way of working out which way round to apply a chain whip to a cassette for its removal? I've taken plenty of them off in my time but always end up having a couple of tries at it ...
2
votes
3answers
229 views

29" freewheel ruined (slipping)

Some time ago I gave a 29" bike to a person for a ride. Someway he ruined the freewheel (it had a shimano freewheel) - the 2 smallest cogs were badly slipping. Now I put another freewheel (also ...
2
votes
3answers
3k views

Shimano MF Z012 replacement Freewheel?

I need to replace my Z012 freewheel due to wear on my 12 speed road bike. I can't seem to find a replacement that matches it. The large gear has 28 teeth and the small has 13. I bought a MF-TZ20 ...
2
votes
1answer
3k views

How to determine size of freewheel?

My previous question was: How to take apart this rear BMX hub? How do I determine the size of my freewheel to replace it? I have seen on bicycle sites that a freewheel comes in sizes like 14t, 16t, ...
2
votes
3answers
8k views

Why is my freewheel slipping?

My freewheel tarted slipping this week. It slips most from a stop with no pressure snapping to significant pressure on the pedals. Slipping may be the wrong term as it really isn't engaging. Once it ...
2
votes
2answers
2k views

Planning on building a fixed-gear/single-speed from an old Schwinn World. What new parts will I need?

I think I want a flip flop hub, to keep my options open. If I get one off amazon, do I need to buy a freewheel and fixed-gear cog as well, or will those come with the hub? Also, does the hub have to ...
2
votes
1answer
137 views

Can anyone identify this freewheel type?

When googling the types it seemed to most closely match a Atom/Regina but it has 25 24 teeth and is about 3.5cm across. It's from a 1980s Raleigh road bike. But the bike has had a lot of work done to ...
2
votes
2answers
4k views

freewheel removal tool for Shimano MF TZ21

I have a Rockrider 5.1 cycle with a Shimano MFTZ21 freewheel. In order to remove the freewheel, I purchased the Btwin tool kit. But the removal tool provided in the kit does not fit on my freewheel. ...
2
votes
1answer
182 views

Can an IGH have the same maximum overdrive-ratio as a crank-sproket setup?

Is there an IGH that gives one the maximum overdrive-ratio that one might get with a 39-53T crankset and a 11-34T freewheel? If not, what is the mechanical roadblock in making one ?