kevinmccune
Well-Known Member
- Region
- USA
how do you get the chain length right? my pal let this formerly good bike lay in the water and mud. changed chain ring.
"Chained in Perdition"
- Thread starter kevinmccune
- Start date
stompandgo
Well-Known Member
- Region
- USA
I do it the old school way. Small chainring, small cog. B screw set. Pull the ends of the chain together and watch the rear derailleur cage. There should be tension on the chain, and the cage should be parallel to the ground, or close to it. The top of the chain should not touch the bottom of the top derailleur pulley.
harryS
Well-Known Member
Per Sheldon Brown's bike bible, wrap the chain around the biggest front/rear gears w/o derailleur, FInd the minimum length to do that and add a link. Because of the way the links are staggered with a big and small end, it;s usually two links,
Done the above way, when threaded thru the derailleur, its arm starts going horizontal on the biggest gears per Stompandgo's post. Department store bikes never go that high so it's OK to add a third link in my opinion..
Done the above way, when threaded thru the derailleur, its arm starts going horizontal on the biggest gears per Stompandgo's post. Department store bikes never go that high so it's OK to add a third link in my opinion..
spokewrench
Well-Known Member
- Region
- USA
If you wonder how many links to add or subtract, take the difference in chainwheel diameters in inches and multiply by pi. That will be the chain difference in half inches, which is the number of links. Then just take the nearest whole number. For example, if you replaced an 8" ring with a 9" ring, that would be an extra inch in diameter, or 3.14 links, so you need to add 3 links.
....Uh-oh, as @harryS says, you have to add or subtract pairs.
I forgot! I guess 3.14 would round to 4.
....Uh-oh, as @harryS says, you have to add or subtract pairs.
I forgot! I guess 3.14 would round to 4.
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kevinmccune
Well-Known Member
- Region
- USA
have to add links anyway,new chain too short.thanks folks,the old chain lay in the mud and water and seized,got it loose,it cannot be trusted I guess I will have to buy a second chain to break and acquire the right length.
Stefan Mikes
Gravel e-biker
- Region
- Europe
- City
- Mazovia, PL
The most precise chain length calculator by Park Tool and @Stefan Mikes
Use on a computer. When the web page opens in the web browser, select "Open in Excel for the Web" or "Open in Excel".
I have used my calculator to verify the chain length for my Vado SL during the derailleur replacement. I needed to correct my previous chain length from 120 down to 118 links and indeed, the derailleur positions itself more properly than ever before!
Use on a computer. When the web page opens in the web browser, select "Open in Excel for the Web" or "Open in Excel".
I have used my calculator to verify the chain length for my Vado SL during the derailleur replacement. I needed to correct my previous chain length from 120 down to 118 links and indeed, the derailleur positions itself more properly than ever before!
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kevinmccune
Well-Known Member
- Region
- USA
sounds great,thank you.The most precise chain length calculator by Park Tool and @Stefan Mikes
Use on a computer. When the web page opens in the web browser, select "Open in Excel for the Web" or "Open in Excel".
I have used my calculator to verify the chain length for my Vado SL during the derailleur replacement. I needed to correct my previous chain length from 120 down to 118 links and indeed, the derailleur positions itself more properly than ever before!
