Increase Timing Chain ring size
06-22-21, 08:38 AM
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Increase Timing Chain ring size
Hi, I need some advise.
My current tandem bike setup as follows:
Timing Chainring = 36T
8-speed rear sprocket = 11 ~ 32T
Rear chain stay = 15.5 inch
Distance between the 2 timing chainring = 24.5 in
Front chain length = 134 links
Rear chain length = 98 links
I would like to change the timing chainring to either 42T or 44T.
Can advise my how many links should I add to front and rear chain?
My current tandem bike setup as follows:
Timing Chainring = 36T
8-speed rear sprocket = 11 ~ 32T
Rear chain stay = 15.5 inch
Distance between the 2 timing chainring = 24.5 in
Front chain length = 134 links
Rear chain length = 98 links
I would like to change the timing chainring to either 42T or 44T.
Can advise my how many links should I add to front and rear chain?
06-22-21, 02:51 PM
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Are you planning to change both timing rings? Are you doing this because you have the parts on hand and the old ones are worn out (and have already been switched) or for some other reason?
06-23-21, 09:12 AM
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Hi climber,
I have a duplicate thread under Bike Mechanics.
The reason for wanting to increase my chainring is stated there.
in short here..
After over the 200km ride, we found that we are riding on the highest gear (ie smallest rear sprocket) most of the time and there is limit to speed that we can go even at a higher cadence.
So, I was thinking to upsize the both the timing chainring and drive chainring from 36T to 42T so that we can have better gear ratio. This is what I learnt from a normal folding bike.
Please give me some advices.
Alvin
I have a duplicate thread under Bike Mechanics.
The reason for wanting to increase my chainring is stated there.
in short here..
After over the 200km ride, we found that we are riding on the highest gear (ie smallest rear sprocket) most of the time and there is limit to speed that we can go even at a higher cadence.
So, I was thinking to upsize the both the timing chainring and drive chainring from 36T to 42T so that we can have better gear ratio. This is what I learnt from a normal folding bike.
Please give me some advices.
Alvin
06-23-21, 10:22 AM
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Hi climber,
I have a duplicate thread under Bike Mechanics.
The reason for wanting to increase my chainring is stated there.
in short here..
After over the 200km ride, we found that we are riding on the highest gear (ie smallest rear sprocket) most of the time and there is limit to speed that we can go even at a higher cadence.
So, I was thinking to upsize the both the timing chainring and drive chainring from 36T to 42T so that we can have better gear ratio. This is what I learnt from a normal folding bike.
Please give me some advices.
Alvin
I have a duplicate thread under Bike Mechanics.
The reason for wanting to increase my chainring is stated there.
in short here..
After over the 200km ride, we found that we are riding on the highest gear (ie smallest rear sprocket) most of the time and there is limit to speed that we can go even at a higher cadence.
So, I was thinking to upsize the both the timing chainring and drive chainring from 36T to 42T so that we can have better gear ratio. This is what I learnt from a normal folding bike.
Please give me some advices.
Alvin
06-23-21, 11:57 AM
#5
Full Member
Agreed, sounds like you want to change your gearing, not your timing chain. In order to determine what you can achieve, you need to know a few parameters of your current bike:
-Rear Derailleur (RD) capacity (how much chain slack the derailleur can handle between the lowest and highest gear in your drivetrain)
-RD max cog size (the largest size cog of the cassette. This is important if you are going for lower gearing as you may want to increase the largest cog. (note you can stretch this to a bit with a derailleur hanger extender (see Wolftooth road link)
- Front D max chain ring difference. max size difference between large and small chainrings.
It's pretty simple once you know these numbers. You can google these terms to understand what they mean and then search for the data for whatever you have. Then you can calculate the current gear ratios you have and then calculate for other cassette and chainring combinations. Once you have the new pieces, you size the chain on the bike by placing the new chain on the largest cog and largest chainring (and not through the derailleur), pull tight and add 2 links.
If you are compelled to change the timing rings to a different size and the chain you have now is the correct size, all you need to do is to add or subtract the number of links equal to the difference in the chain ring sizes. For example, you currently have 36 tooth rings and 134 links and you want to go to 42 teeth rings: 42-36=6, so add 6 links to your timing chain length.
-Rear Derailleur (RD) capacity (how much chain slack the derailleur can handle between the lowest and highest gear in your drivetrain)
-RD max cog size (the largest size cog of the cassette. This is important if you are going for lower gearing as you may want to increase the largest cog. (note you can stretch this to a bit with a derailleur hanger extender (see Wolftooth road link)
- Front D max chain ring difference. max size difference between large and small chainrings.
It's pretty simple once you know these numbers. You can google these terms to understand what they mean and then search for the data for whatever you have. Then you can calculate the current gear ratios you have and then calculate for other cassette and chainring combinations. Once you have the new pieces, you size the chain on the bike by placing the new chain on the largest cog and largest chainring (and not through the derailleur), pull tight and add 2 links.
If you are compelled to change the timing rings to a different size and the chain you have now is the correct size, all you need to do is to add or subtract the number of links equal to the difference in the chain ring sizes. For example, you currently have 36 tooth rings and 134 links and you want to go to 42 teeth rings: 42-36=6, so add 6 links to your timing chain length.
