How to change a casette?

[Triskeliongirl]

OK girls. Any wrenches out there want to tell me what tools I need to buy to change a casette, and how hard it is to do? I have a wheel I bought from Emily on this board (thanks Emily, she is beautiful !) that came with a shimano 105 13-23 casette on it and I want to replace it with an ultegra 12-27 casette. The current wheel on my touring bike has an 11-34 XT casette with an XT rear derailleur, so the bike is already tuned to run with the 11-34 casette. Will I expect to have to adjust the derailleur much when I put on the 12-27? In the future how easy will it be to swap these 2 wheels back and forth? It seems since they are both 9 spd, and the cogs on the 12-27 are within the range of the 11-34 that it should swap easily and not require adjustment. Does what I wanna do make sense. I know the 12-27 will work most of the time, but if I need to carry a heavy load I want to be able to use the 11-34, or if I want to ride it on the trainer without wearing out the nicer tires I may want to swap it.

[Veronica]

You'll want to have a chain for each cassettte.

Tools: you'll need to have a chain whip and a "cassette socket tool" to take the retaining nut off. I don't know what it's real name is.

V.

[Triskeliongirl]

Why do I need a different chain for each casette? The chain on there now is pretty new. I have read that chains and casettes wear together, but if you change the chain before it is too stretched why do you need a separate chain. Doesn't it weaken the chain to take it off and replace the pin?

[velogirl]

I disagree that you need a chain for each cassette. If you change your chain frequently (I recommend every 1,500-2,000 miles), your cassette won't conform to any stretched chain patterns.

I swap wheels on my various bikes all the time. I have race wheels, training wheels, disk wheels, cyclocross wheels. And most of them have been on all my bikes. It's a piece of cake and you shouldn't have to adjust your rear derailleur if you're using cassettes from the same mfg (Shimano or Campy) and the same speed (8, 9, 10). I've even run a Shimano 9 on a Campy 10 and it worked just fine.

To swap the cassette, you need a crescent wrench, a chain whip, and a cassette tool (it's a little round thing that you place on the lock-ring). Make sure you get the correct cassette tool for your component group (campy or shimano). I use the same chain whip for Campy or Shimano, 9 or 10 -- doesn't seem to make a difference (although someone hardcore might disagree).

Swapping cassettes is challenging at first, but once you remember which way to place the chain whip, it's a piece of cake!

[susan.wells]

Check the Park Tool Site > Cassette and Freewheel Removal

[DebW]

Then there was the cassette that Newfsmith had which someone had tightened too tight. It took a bench vise, a lockring tool, a chainwhip, and a 24 inch piece of pipe to get it off. For a lockring tool, the kind with the center post are nice because sometimes your quick release skewer isn't long enough to hold the tool onto the wheel. Also note that putting the chainwhip on a larger cog gives you more leverage.

[Triskeliongirl]

Thanks for all the great advice guys! I think I can do this. I am off to buy some new tools. Regarding how frequently to change the chain. Do you change it every 1500-2000 miles regardless of stretch, or do you measure it with one of those stretch rulers, and change it when it enters the high end of the acceptable range? I had forgotton that I used to swap wheels all the time on my old bike between trainer and road, although the casette sizes were identical. Swapping wheels seems like a great way to rapidly modify gearing depending on the planned ride terrain.

[DebW]

Regarding how frequently to change the chain. Do you change it every 1500-2000 miles regardless of stretch, or do you measure it with one of those stretch rulers, and change it when it enters the high end of the acceptable range?

That's really a personal decision. Some people will use a chain until it starts to skip over the cassette cogs, but you are more likely to need to replace cogs also that way. If you plan to swap these two wheels, better to be more conservative and change the chain early.

[Mags...]

[QUOTE=velogirlI use the same chain whip for Campy or Shimano, 9 or 10 -- doesn't seem to make a difference (although someone hardcore might disagree).[/QUOTE]

is the chain whip tool necessary, or is there some other tool or combination of tools that can be used instead?

[DebW]

is the chain whip tool necessary, or is there some other tool or combination of tools that can be used instead?

There is also Pedro cog wrench which can be used instead of a chain whip:
http://www.nashbar.com/profile.cfm?c...eid=&pagename=

But it only works on 11 or 12 tooth outer cogs. A chain whip is more versatile since it fits any size cog in any position. If you have to buy a tool, get a chain whip. Or you could make your own from a piece of metal bar and some old chain.

[bcipam]

I switch out my 12-27 for a 12-34 (I put a XTR cassette and derailleur on the rear) and I did need a new chain - the original was just not long enough. If you keep the longer chain on when switching to the 27, then it will be too long and you will have chain slack. There really is a big difference between a 27 and a 34 not so much if you are switching out a 27 for a 25 or 23. Suggestion - have a chain for each cassette. Use a Conex link so it's easy to remove and replace. When you are using one you can be cleaning hte other. Probably not a bad idea. Also you will need a different derailleur for the 34. The regular Ultegra or whatever you run just isn't long enough. You need a mountain bike or touring derailleur.

Note: I put the XTR on3 years ago for my Utah trip but never replaced it with the 27. Turns out I like having the 34. Are you sure you will be changing the casettes out?

Also to change out a cassette you need two tools - a chainwhip and I forget the name of the tool that goes in the middle. One holds the hub tight , the chainwhip loosens the cassette. I would got o your LBS and ask them to show you how to change out the casette and what tools you need. Neither was particularly expensive.

Also there is a cheap tool you can buy that measures chain wear. I think wear varies for each rider and how hard they mash their gears.

[Eden]

Thanks for all the great advice guys! I think I can do this. I am off to buy some new tools. Regarding how frequently to change the chain. Do you change it every 1500-2000 miles regardless of stretch, or do you measure it with one of those stretch rulers, and change it when it enters the high end of the acceptable range? I had forgotton that I used to swap wheels all the time on my old bike between trainer and road, although the casette sizes were identical. Swapping wheels seems like a great way to rapidly modify gearing depending on the planned ride terrain.

It's not so bad for most of us gals - being smaller and lighter than the guys, but my husband destroyed a cog set by waiting until the chain stretch tool told him it was time to change the chain. He's started changing his chain on a strictly time based schedule, figuring its cheaper to change the chain out more than he needs to than to have to buy new rear clusters...

[velogirl]

A chain whip is more versatile since it fits any size cog in any position. If you have to buy a tool, get a chain whip. Or you could make your own from a piece of metal bar and some old chain.

And how cool is it at a cocktail party when you can tell that cute guy about using your chain whip?

[Triskeliongirl]

I switch out my 12-27 for a 12-34 (I put a XTR cassette and derailleur on the rear) and I did need a new chain - the original was just not long enough. If you keep the longer chain on when switching to the 27, then it will be too long and you will have chain slack. There really is a big difference between a 27 and a 34 not so much if you are switching out a 27 for a 25 or 23. ... Also you will need a different derailleur for the 34. The regular Ultegra or whatever you run just isn't long enough. You need a mountain bike or touring derailleur.

Note: I put the XTR on3 years ago for my Utah trip but never replaced it with the 27. Turns out I like having the 34. Are you sure you will be changing the casettes out?...

On this particular bike, I have an XT dearilleur, longer chain, and 11-34. But, its not clear the chain will have too much slack when I move to the 12-27, since it seems to me that since 12 and 27 are both contained within my 11-34 casette, then the slack should be the same when in those gears. But, I'll see when I go to do it. I know I don' tlike the 11-34 for everyday use, cuz the gaps between gears is too large for fast club riding, etc., BUT, if I go to the real mountains or tour I will want it. I am also curious to see how I like the XT rear dearailleur with the 12-27. If its OK, when my racing bike needs a new rear derailleur I may put an XT or XTR on instead of the ultegra I have, again with the idea that I can easily swap casettes ore wheels as needed for the terrain, since I only have a compact double, and not a triple on both bikes.

[bcipam]

I toy with putting the Ultegra 27 back on - as the XTR 34 is alittle clunkier - bigger changes/jumps between shift etc but I love having the small granny gear when I need it. Helped me out in Utah and Texas on some long steep climbs!