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36

Do you hear a "tick" sound every time you spin the wheel anti-clockwise? that's the freewheel mechanism composed by two small parts called "pawls" and when you spin it on that direction, those pawls turn loosely until they find the "dent" in the inner mechanism (the ratchet body), that's when the "tick" sound happens. When you ride your bike, those two ...


11

Most of the noise comes from pawls on the freewheel hitting against the splines on the engagment surfaces which makes up the racheting unit. Some reasons for the noise between freewheels? Tension on pawls could be higher causing more noise as they glide over the engagment surfaces High end freewheels have more pawls and engagement points than lower end ...


11

For the same reason you can't have a fixie with a chain tensioner. The load on the chain when slowing a fixie is too great and in the wrong direction for a derailler or tensioner to hold. The cage will be pulled forward and your chain will skip make a nasty noise and most likely come off or break something expensive.


10

If you take the back wheel off you should be able to examine the freewheel/cassette to determine which it is. Here is a picture of some common types. If yours doesn't look like one in the picture, post a close up and I'm sure someone here can identify it.


8

That particular Shimano freehub can be disassembled, but it is quite a job to get it back together afterward. There are around 80 2mm bearings in two different locations in the freehub, and a skilled and practiced mechanic has roughly a 60% chance of opening without losing parts, and successfully getting it back together. The good news is, there is a tool ...


8

From personal experience, having just changed to a cassette with less range, I have to say that smaller steps definitely offers some advantage. I went from an 8-speed 11-32 to a 12-23. Having a single tooth of difference between adjacent gears means that it's more likely that you will be in the "right gear". The "right gear" is the gear in which you aren't ...


8

The point is efficiency. Cyclists actually have quite a narrow optimal power band. Most of us can bang away at a cadence of 50 rpm, up to about 90 rpm. Some of us pedal faster - 90 to 120 rpm. At those lower cadences (50) it feels like we're producing lots of power and at the high cadences it feels like we're just breezing along. But that is confusing ...


7

Your hub has a normal freewheel, like described by Matt Adams (ratchet with pawls). There are some models which have spring-loaded cilinders mounted around "tilted" teeth: when you spin it to one side, the cilinders slip. When you spin it to the other side, the cilinders are caught between opposite surfaces, and torque is transmitted by friction (there is ...


7

There's not much you can do aside from cleaning your drivetrain often and thoroughly. In the winter, ice is far less of a mechanical issue than is rock salt. You may indeed have some corrosion in the entire drivetrain by this point, not just the deraileur, or possibly just dirt if you're lucky. I'd do one major cleaning at this point, and see if that takes ...


6

The hub is adjusted too tight, or there is damage to the bearing track which cause higher than normal friction when the bearings are compressed. You're on the right track.


6

If you're saying that, off the body, the sprockets move slightly relative to each other, that's not a problem. The sprockets are only just "tacked" together so that they remain in the right order and orientation while off the body. The body provides the strength to hold them. If, on the other hand, you notice that the sprockets slide up and down the body ...


6

The hub is the body at the center of the wheel containing the axle. It is more or less just some bearings in a pair of cups that rotate around the axle. The freewheel is the mechanism that locks when pedaling forward (forcing the wheel to be driven by the chain) and spins freely when coasting or pedaling backward. These are two variations on freewheel ...


6

The first thing to note is "Does the 8 speed hub clear the dropouts ?" You may be able to spread the frame if steel. Since you're likely going from a 120mm to 130 mm (which is 2 sizes - 120->126->130), you should be cold setting it. The second question would be "Can the brakes reach the rim?" Unfortunately, to my knowledge, nobody makes a 5 speed ...


5

Short answer. Hub integrity can not really be judged by noise alone, but by feel. If you feel it slipping under load the hub could be damaged beyond repair. The quiet smooth feel, but working normally is just a good, sealed hub that the manufacturer built in a way that has smaller or less splines. The full monty. A free wheel hub consists of a few key ...


5

The freewheel allows forward pedalling to lock and drive the bike, but spins freely when reversed. Some BMX style bikes (and kids bikes) have coaster brakes, where if you pedal backwards (well usually they do not actually pedal backwards, just the motion is begun) and it brakes the bike. I remember well locking the back wheel and trying to generate skid ...


5

It means the bearings are loose. (The main bearings, not the freewheel bearings.) It could be they're worn, but it's also likely that at some point in maintaining the bike you accidentally unscrewed one of the cups. I'd suggest you take it to a bike shop. They should be able to fix it in about 3 minutes (though there's some danger that the bearings are ...


5

the 14t, 15t, etc. is the number of teeth. You currently have a 16 tooth or 16t freewheel. More teeth and the easier to spin, but the slower it spins. Think of teeth on the rear cog as inverse to ease...lower numbers take more power to move; higher numbers take relatively less power. You want to find a good mix that allows you to make it up whatever hills ...


5

The 14/28 is the number of teeth on the smallest and largest cog of the cassette. From your description you want to make at least the second number smaller, possibly the first number. As long as your replacement says that it's Shimano compatible (and 7 speed), you should be fine. Count the teeth on the cog that has the most teeth that you actually ...


5

Police / Law Enforcement bikes often have a quiet freehub. This Cannondale Law Enforcement bicycle refers to it as a "Silent Clutch Rear Hub" and specifically mentions "R085" as a model number (further googling suggests it's a Shimano).


5

No, it is not a good idea. You'd be spending more than the bike is worth even for a basic internal gear hub (even assuming you got the wheel rebuilt for free using the existing rim and spokes, if possible), let alone buying a rear wheel with an IGH built in. You do need a chain tensioning pulley or horizontal dropouts, which while can be built more robustly ...


5

I'm betting that you need to install a brand new chain and a brand new freewheel / cassette, at the same time, and out of an abundance of caution, make sure they're the same brand. I doubt your friend actually ruined anything, the more likely scenario is that the chain is old and stretched, causing it to slip ( or it's the wrong length as Daniel mentioned ). ...


4

This sounds like either the freehub on the rear wheel, if you have the newer cassette style, or the freewheel, if you have the older thread on design, needs to be replaced. These parts contain the pawls which drive the wheel forward when you pedal. If the pawls are broken, or simply not engaging the hub shell, you will pedal with no forward movement. See ...


4

It very much depends on the freewheel mechanism in the hub, some make a nice "clickerty" noise, others are more silent. The hub will be sealed and this should prevent dirt etc. getting into the mechanism. If anything it is likely to get noisier with penetration by dirt & grit rather than quieter. Looking at the bike spec, my experience of Shimano hubs ...


4

I had the same problem (48x38x28 chainset). It turned out that MF-TZ21 is actually not a 'cassette', but a 'freewheel'. Your options for that are very limited: In the UK, Raleigh is distributing a 7 speed 13-24T model for less than 10 quid. SunRace is still producing 7 speed freewheels, but the closed-spaced 12-?? model wasn't distributed in the UK: Check ...


4

Really any 6 speed freewheel will work. You'll want to get the tooth numbers close, but they don't have to be exact (your 14-28 will be a fine replacement.) Chain sizing for 6-7-8 speed drivetrains hasn't been significantly changed since they became popular, though the profiles and faces of the freewheel cog teeth have, in most brands, been altered to ...


4

I love ATF (Automatic Transmission Fluid) for freewheel (not free hub) lube. What I do is lift the bike-- if someone can help you with this, it's a bit easier-- so that you can rotate the pedals (and make the back wheel spin). Ideally, the bike should be tilted to the non-drive side about 45-60 degrees. With the back wheel rotating, you can see where to ...


4

Its likely disassembles in one of two ways: two cone wrenches (one on each side of the hub) to remove the jam nuts. This is the likely option. From your photo it looks like there is a flat spot on the jam nut. two hex wrenches (one on each side of the hub) that fit into the axle end. Two videos demonstrating these techniques: http://aol.it/15nYDub ...



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