How do I change my cassette and chainrings?
03-06-20, 01:15 PM
#1
QR-disc must die!!!
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Bikes: '99 Trek 520, '20 Kona Sutra (FOR SALE 48cm), '21 Simon-Bikes mini-velo and a chromoly-framed folding bicycle with drop-bars and V-brakes, that rolls even while folded.
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How do I change my cassette and chainrings?
Hola touristas,
On my Trek 520, I have an 8-speed Shimano "Megarange" 11-34 cassette, which is far from ideal, due to an 8-tooth gap near the low end. I would like to change to an 11-32 cassette, as well as change the 30t chainring on the stock Shimano-105 crank to 26t (stock is 52/42/30). Among several issues this would address, is that it gets me to approximately 16 gear-inches. But I want to know a few things about this plan:
These are 20-year old components that came stock on the bicycle. The hub is a Deore LX, the crank a 105, the r.derailer is Deore LX long-cage and the f.derailer is 105 for triple ring crank. It all runs very smooth and I'd like to not make any change that will result in a change that is less smooth than before (compared to a modern Shimano Deore triple crank and 10-speed setup, this old 105 is super smooth). I've also bought an N-Gear "JumpStop", which will be used to ensure that the chain makes a proper engagement with the smallest chainring.
1. What chainring in 26t should I look for that will be just as smooth as the 30t one that would be replaced?
2. Since the jump from 42t to 26t is so great, should I consider changing the 42t to something lower as well? I want to keep using the 52t.
3. Should I look for any particular cassette brand/model or, is something like an 8-speed SunRace 11-32 cassette optimally compatible?
4. Will it be easy to tune this setup myself or, should I get the LBS to do it? I'd prefer to be able to do this myself, as there are similar projects waiting for other bicycles that I own/will-own.
Thanks for any help y'all give me!
On my Trek 520, I have an 8-speed Shimano "Megarange" 11-34 cassette, which is far from ideal, due to an 8-tooth gap near the low end. I would like to change to an 11-32 cassette, as well as change the 30t chainring on the stock Shimano-105 crank to 26t (stock is 52/42/30). Among several issues this would address, is that it gets me to approximately 16 gear-inches. But I want to know a few things about this plan:
These are 20-year old components that came stock on the bicycle. The hub is a Deore LX, the crank a 105, the r.derailer is Deore LX long-cage and the f.derailer is 105 for triple ring crank. It all runs very smooth and I'd like to not make any change that will result in a change that is less smooth than before (compared to a modern Shimano Deore triple crank and 10-speed setup, this old 105 is super smooth). I've also bought an N-Gear "JumpStop", which will be used to ensure that the chain makes a proper engagement with the smallest chainring.
1. What chainring in 26t should I look for that will be just as smooth as the 30t one that would be replaced?
2. Since the jump from 42t to 26t is so great, should I consider changing the 42t to something lower as well? I want to keep using the 52t.
3. Should I look for any particular cassette brand/model or, is something like an 8-speed SunRace 11-32 cassette optimally compatible?
4. Will it be easy to tune this setup myself or, should I get the LBS to do it? I'd prefer to be able to do this myself, as there are similar projects waiting for other bicycles that I own/will-own.
Thanks for any help y'all give me!
03-06-20, 02:03 PM
#2
The dropped
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You should be able to do this yourself, if you have the tools. I'd recommend sticking with Shimano components, since you aren't at the bleeding edge of componentry. The rear cassette is easy enough, find a Shimano cassette with the high end you want and the number of gears to match your shifter (if you're using SIS). If the lack of intermediate steps in your gearing is a concern, consider moving to 9 cogs.
The chainrings are a little tougher. You'll need to know the bolt circle diameter for your crankset's inner bolts, and find a chainring using that number. Changing the middle ring might be necessary, depending on any pins and ramps it has. I'd tune it and ride it a little before making that decision.
The chainrings are a little tougher. You'll need to know the bolt circle diameter for your crankset's inner bolts, and find a chainring using that number. Changing the middle ring might be necessary, depending on any pins and ramps it has. I'd tune it and ride it a little before making that decision.
03-06-20, 02:10 PM
#3
The dropped
Join Date: Oct 2018
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Bikes: Pake C'Mute Touring/Commuter Build, 1989 Kona Cinder Cone, 1995 Trek 5200, 1973 Raleigh Super Course FG, 1960/61 Montgomery Ward Hawthorne "thrift" 3 speed, by Hercules (sold) : 1966 Schwinn Deluxe Racer (sold)
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If you're using the FC 5505 with a 74 BCD, Harris Cyclery has a page for you.
03-06-20, 03:46 PM
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I have no clue if you have a square taper crank or something else. If not square taper, someone else will need to advise.
Square taper, you need a crank arm puller, they are reasonably cheap. You could look for a you tube video or two or three to learn how to do it. I think this is a good yet inexpensive square taper crank arm puller, works with 15mm open end wrench which is a common pedal wrench size. I have to pull the crank arms off of one of my bikes for packing it for travel, I use this puller for that.
https://www.amazon.com/XLC-Cotterles...dp/B000NU2WAS/
If it is square taper, you have to make sure you get the crank arm back on tight enough, if it starts to make any creaking noise at all it is too loose and riding it that way can ruin it, would have to be tighter. A long arm 8mm allen wrench is used for that.
I assume you are using a bar end shifter that is friction for the front. It might shift a bit more difficult up to the 42 from the 26, but should not be a deal killer. I find that I have to over-shift a bit, move the shift lever a bit farther than needed and then back off a bit when I upshift to my 42. If the crank has five arms on it, it probably is a 74mm chainring, you could use a 26 instead of your 30.
This is a good way to check measurements. If you have a four arm crank, some of the newer ones are not listed here, someone else will have to advise you on that.
https://www.sheldonbrown.com/cribsheet-bcd.html
I use a middle chainring that is 42 and granny gear that is 24T on two of my touring bikes, photo below. My big chainring is 46, not 52. I have an 11/32 eight speed Sram cassette on the bike in the photo. I have been very happy with Sram eight speed cassettes. Photo is obviously not a Trek 520, but the drive train is similar to what you are talking about.
I think you might want a chain catcher, that is intended to make it harder to drop your chain to the wrong place when shifting down to the 26. That is something you can add later if you find you need it.
There probably are you tube videos on how to remove a cassette from the wheel, you need a chain whip, a cassette puller and an adjustable wrench to put on the cassette puller. Cassette tool looks like this, I think this one needs a one inch wrench.
https://www.amazon.com/Park-Tool-FR-...dp/B01LX3E08Z/
You probably will find that you can't use a couple of the smallest cassette sprockets with the smallest chainring because the derailleur cage might not be able to take up all the slack when you are using the 26T chainring. If you are pedaling along and shift and start hearing weird noises when you are using the 26T chainring, that is a sign that your cage could not take up all the slack. But those gears are highly cross chained, you should not use them anyway.
Square taper, you need a crank arm puller, they are reasonably cheap. You could look for a you tube video or two or three to learn how to do it. I think this is a good yet inexpensive square taper crank arm puller, works with 15mm open end wrench which is a common pedal wrench size. I have to pull the crank arms off of one of my bikes for packing it for travel, I use this puller for that.
https://www.amazon.com/XLC-Cotterles...dp/B000NU2WAS/
If it is square taper, you have to make sure you get the crank arm back on tight enough, if it starts to make any creaking noise at all it is too loose and riding it that way can ruin it, would have to be tighter. A long arm 8mm allen wrench is used for that.
I assume you are using a bar end shifter that is friction for the front. It might shift a bit more difficult up to the 42 from the 26, but should not be a deal killer. I find that I have to over-shift a bit, move the shift lever a bit farther than needed and then back off a bit when I upshift to my 42. If the crank has five arms on it, it probably is a 74mm chainring, you could use a 26 instead of your 30.
This is a good way to check measurements. If you have a four arm crank, some of the newer ones are not listed here, someone else will have to advise you on that.
https://www.sheldonbrown.com/cribsheet-bcd.html
I use a middle chainring that is 42 and granny gear that is 24T on two of my touring bikes, photo below. My big chainring is 46, not 52. I have an 11/32 eight speed Sram cassette on the bike in the photo. I have been very happy with Sram eight speed cassettes. Photo is obviously not a Trek 520, but the drive train is similar to what you are talking about.
I think you might want a chain catcher, that is intended to make it harder to drop your chain to the wrong place when shifting down to the 26. That is something you can add later if you find you need it.
There probably are you tube videos on how to remove a cassette from the wheel, you need a chain whip, a cassette puller and an adjustable wrench to put on the cassette puller. Cassette tool looks like this, I think this one needs a one inch wrench.
https://www.amazon.com/Park-Tool-FR-...dp/B01LX3E08Z/
You probably will find that you can't use a couple of the smallest cassette sprockets with the smallest chainring because the derailleur cage might not be able to take up all the slack when you are using the 26T chainring. If you are pedaling along and shift and start hearing weird noises when you are using the 26T chainring, that is a sign that your cage could not take up all the slack. But those gears are highly cross chained, you should not use them anyway.
Last edited by Tourist in MSN; 03-11-20 at 11:47 AM.
03-10-20, 08:52 AM
#5
Miles to Go
I would like to add a "second" on SRAM 8 and 9 speed cassettes. Work well with the rest of the Shimano components. If you end up wanting to replace two rings, you may be able to change the entire crankset to something more appropriate "touring crankset" (26/36/48) for not too much more and get better overall gearing. The will change your 130MM BCD crankset to 110mm BCD which will provide better options for lower geared rings for touring.
03-10-20, 03:09 PM
#6
Senior Member
Hola touristas,
On my Trek 520, I have an 8-speed Shimano "Megarange" 11-34 cassette, which is far from ideal, due to an 8-tooth gap near the low end. I would like to change to an 11-32 cassette, as well as change the 30t chainring on the stock Shimano-105 crank to 26t (stock is 52/42/30). Among several issues this would address, is that it gets me to approximately 16 gear-inches. But I want to know a few things about this plan:
These are 20-year old components that came stock on the bicycle. The hub is a Deore LX, the crank a 105, the r.derailer is Deore LX long-cage and the f.derailer is 105 for triple ring crank. It all runs very smooth and I'd like to not make any change that will result in a change that is less smooth than before (compared to a modern Shimano Deore triple crank and 10-speed setup, this old 105 is super smooth). I've also bought an N-Gear "JumpStop", which will be used to ensure that the chain makes a proper engagement with the smallest chainring.
1. What chainring in 26t should I look for that will be just as smooth as the 30t one that would be replaced?
2. Since the jump from 42t to 26t is so great, should I consider changing the 42t to something lower as well? I want to keep using the 52t.
3. Should I look for any particular cassette brand/model or, is something like an 8-speed SunRace 11-32 cassette optimally compatible?
4. Will it be easy to tune this setup myself or, should I get the LBS to do it? I'd prefer to be able to do this myself, as there are similar projects waiting for other bicycles that I own/will-own.
Thanks for any help y'all give me!
On my Trek 520, I have an 8-speed Shimano "Megarange" 11-34 cassette, which is far from ideal, due to an 8-tooth gap near the low end. I would like to change to an 11-32 cassette, as well as change the 30t chainring on the stock Shimano-105 crank to 26t (stock is 52/42/30). Among several issues this would address, is that it gets me to approximately 16 gear-inches. But I want to know a few things about this plan:
These are 20-year old components that came stock on the bicycle. The hub is a Deore LX, the crank a 105, the r.derailer is Deore LX long-cage and the f.derailer is 105 for triple ring crank. It all runs very smooth and I'd like to not make any change that will result in a change that is less smooth than before (compared to a modern Shimano Deore triple crank and 10-speed setup, this old 105 is super smooth). I've also bought an N-Gear "JumpStop", which will be used to ensure that the chain makes a proper engagement with the smallest chainring.
1. What chainring in 26t should I look for that will be just as smooth as the 30t one that would be replaced?
2. Since the jump from 42t to 26t is so great, should I consider changing the 42t to something lower as well? I want to keep using the 52t.
3. Should I look for any particular cassette brand/model or, is something like an 8-speed SunRace 11-32 cassette optimally compatible?
4. Will it be easy to tune this setup myself or, should I get the LBS to do it? I'd prefer to be able to do this myself, as there are similar projects waiting for other bicycles that I own/will-own.
Thanks for any help y'all give me!
I get it that everyone has to start somewhere, so I would suggest that you look at the excellent video series by Parks Tools. They have well made, reliable, ie good info that will help you understand the procedures.
Doesnt make up for real hands on, interweb Q and A's can only do so much, but there you go.
good luck
I also suggest getting a good relationship with a real bike shop. You can let them know you want to learn to do things yourself, but pay them at times if necessary to check your work.
