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
3k 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?
9
votes
2answers
6k 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
475 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
201 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
236 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
835 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
3answers
364 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
1answer
180 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 ...
4
votes
1answer
177 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
387 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
2answers
3k 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 ...
4
votes
1answer
574 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
172 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
7answers
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 ...
3
votes
3answers
139 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
192 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
117 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
5k 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
4k 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
3answers
1k 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
7k 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
11k 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
107 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
1k 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
250 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
109 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
86 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
464 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
895 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
384 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
892 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
696 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
348 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
52 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
110 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
257 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
405 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
51 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
237 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
70 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 ...