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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22
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2answers
4k views

What's stopping you from pedalling backwards?

On the BMX bike I have, pedalling backwards moves the chain but doesn't drive the wheels of the bike backwards like you would expect it to. Why is this?
12
votes
3answers
9k 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
500 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
206 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 | ...
6
votes
4answers
253 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
4answers
3k 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 ...
6
votes
1answer
881 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 ...
5
votes
1answer
319 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
378 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
5answers
9k 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 ...
4
votes
9answers
3k 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 ...
4
votes
1answer
286 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
417 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
1k 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
731 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?
4
votes
1answer
182 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 ...
3
votes
3answers
218 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
1answer
2k 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? ...
3
votes
2answers
3k 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 ...
3
votes
1answer
231 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 ...
3
votes
2answers
1k 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 ...
3
votes
2answers
122 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 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
5k 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
4k 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 ...
3
votes
3answers
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 ...
3
votes
3answers
8k 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?
2
votes
2answers
2k 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 ...
2
votes
2answers
13k 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 ...
2
votes
2answers
129 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
2k 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
2answers
2k 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 ...
2
votes
2answers
845 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
2answers
112 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
1answer
108 views

Can you change a 7 speed freewheel to 6 speed

Can you change a 7 speed freewheel to a 6 speed
2
votes
1answer
559 views

Do new wheels usually come with freehubs?

I was looking around for new wheels and thoroughly confused about the common approach to freehubs. Do they usually come with the freehub or do I have to actually put that on? If they do come with ...
2
votes
5answers
929 views

Home-made sealed freewheel?

Is there any way to do a home-made sealing on my freewheel? Is there any material recommended to do it? Anyone can find some previous try documented? Will I fail miserably if I try to source a ...
2
votes
3answers
456 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 ...
2
votes
2answers
1k 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
807 views

How does one test the freewheel?

What are the failure modes (symptoms) of a failing or failed freewheel? My understanding of normal free wheeling means the rear tire should rotate when the bike is moving and the pedals are or are ...
2
votes
1answer
382 views

What hub to purchase for a GT aggressor?

I have a GT Aggressor 1.0 Specs here: http://www.gtbicycles.com/2013/bikes/mountain/trail/aggressor-1-0 Recently on a long ride, the crank started to roll freely after a long downhill. i.e. when ...
2
votes
2answers
66 views

Changing from 5 to 6 cog freewheel on 1986 Stumpjumper-Sport

Refining a prior posted question. 15 speed 1986 Specialized Stumpjumper-Sport has original 5 cog freewheel, 14-30. Original Analog shifters. Biggest cog needs replacement. Individual cogs are no ...
2
votes
1answer
121 views

Older road freewheels vs new mountain bike freewheels?

I heard an interesting opinion yesterday that said all freewheels made back in the day (we were discussing this over a wheel with a Maillard hub and a Maeda (?) freewheel). The shop mechanic said that ...
2
votes
1answer
273 views

Unknown freehub, trying to source

I have a neighbours daughters bike to fix at the moment. The freehub is totally seized. I've removed the freehub from the hub itself, but can't identify it nor have I see any like it. It doesn't have ...
2
votes
1answer
427 views

What crankset should I buy to suit an 8 Speed Campy freehub?

I've just bought a pair of campagnolo/mavic wheels without a freewheel. I'm finding it very hard to understand what will fit on the rear hub. It's English thread, does this mean that any 8 speed ...
2
votes
0answers
70 views

My BionX system won't work in assistance mode, and makes a weird noise

I've had to remove and reinstall my rear wheel because of a flat, and now the BionX system has stopped working correctly. When I turn it on, it works fine, and the regenerative breaking works fine. A ...
1
vote
3answers
326 views

Theoretical question about double drivetrain (both-sides drive)

If one were to take a single-speed flip-flop hub, and fit two identical freewheels, and couple them to two identical chainrings (i.e. two drive-side cranks, one on each side of the bike), you would ...
1
vote
1answer
2k 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, ...
1
vote
3answers
6k views

removing freewheel MF-Z012 without tools

I'm trying to just add some grease to an old MF-Z012. some pages online says i can remove it just by spining the first gear agains the last one.(e.g. ...
1
vote
3answers
81 views

1986 Stumpjumper Sport Cog Replacement

Original Shimano Deore components all around. Shimano MF Z012 5-cog freewheel. Biggest cog is 30 teeth is worn out, chain skips, and that cog needs to be replaced. Rest of cogs are ok. Are ...