Bicycle Mechanics - one of the cogs on my rear cassette is broke

The cog thingy broke, it's still ridable, just no 5th gear. Can I buy an individual cog, or do I have to buy a whole new cassette?

GQ

Thanx!

The cog thingy broke, it's still ridable, just no 5th gear. Can I buy an individual cog, or do I have to buy a whole new cassette?

GQ

Thanx!

Depends. Some cogs are available separately, some only as a set riveted to one or more other cogs. As a general rule, an individual cog will be about 1/3 the cost of a whole cassette so if your cassette has any appreciable wear on it, it's usually cost effective to replace the whole thing.

If you call it a "cog thingie" you need to take your bike to your LBS

Nah, don't succumb to going to your LBS just yet for the repair, (except perhaps for advice or to make sure you order the correct part, though this isn't necessarily a given as I've learned so keep reseraching on your own from various sources too) because you don't know the names of parts, that's the learning curve and it takes a while. I've been working on my bike for almost a year now and I still forget the names of parts I've worked on before, it's hard to remember when you only refer to them or work with them once in a blue moon. And some of us aren't detail minded when it comes to names etc, unless they are a part of our routine, just how certain minds work in my experience.

Don't get me wrong, support your LBS for sure if you can afford to and need to, or don't have the time to do it yourself. But try, try, try to learn it on your own first. Give a man a fish .....

You'll need a lock-ring tool and a chain whip (or an old chain) to get the cassette off the rear wheel. At that point, the first cog or two might come off loose, but the rest will be held together either by three long skinny bolts or by three rivet pins. If it's bolts, just remove them to get to the broken cog. If it's rivets, grind off or drill out the heads at one end. Just make SURE you maintain the order of cogs and spacers!! Put them on a loop of wire or piece of string, as you separate them. Technically, if it's riveted, you don't really need the rivets to hold it together again once it's back on the hub; it's the lock-ring that holds everything together.

In any event, whether you do this yourself or have the LBS do it is in great part a function of whether you want to invest in the tools (that is, whether you expect to use them again).

For the cost (~$20), its more effective to replace it. Now to do it yourself, you'll need the tool to remove the cassette and a chainwhip, probably in the ballpark of another $20. And a big wrench.

So you have to decide whether or not to do it yourself. The last time I had my LBS do it (before I aquired more bikes and the tools to fiddle about with), they charged me ~$40 to replace the cassette and the chain.

How often you use gear #5, anyway?

How often you use gear #5, anyway?

Would kind of depend on:

-How many speeds he's got
-Which way he's counting
-The type of terrain he's going through

Since I try to maintain a good cadence, I'm constantly moving through the highest 3-4 gears. Having one shot is a big jump in the gearing.