Chain length
12-05-14 | 04:57 PM
#3
Really Old Senior Member
Joined: Feb 2007
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From: Mid Willamette Valley, Orygun
Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds. 2019 Giant Explore E+3
Think about it-
Would you expect a large frame bike to have exactly the same length chain stays as a small?
Also consider the different size chain rings or cassettes largest cog.
Would you expect a large frame bike to have exactly the same length chain stays as a small?
Also consider the different size chain rings or cassettes largest cog.
12-05-14 | 05:28 PM
#4
Senior Member
Joined: Feb 2012
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From: Rochester, NY
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Bill- While I agree with you about bike size and chain length (or chain stay length actually) most of the mainstream bike industry doesn't see the need for a larger bike to have longer chain stays. One more example of market driven frame design IMO. Andy.
12-05-14 | 05:39 PM
#5
Really Old Senior Member
Joined: Feb 2007
Posts: 14,643
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From: Mid Willamette Valley, Orygun
Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds. 2019 Giant Explore E+3
I don't look at a lot of bike specs, it seems at least some manfs. will use 2 lengths to span the gap from extra small to extra large frames.
12-09-14 | 10:39 AM
#7
Isn't somebody going to tell him how to properly size his chain?
12-09-14 | 10:50 AM
#8
Senior Member
Joined: Apr 2009
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From: New Rochelle, NY
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
Hey, the the OP has a derailleur bike, so here at BF people feel free to derail the post.
To answer the original question.
New chains are usually sold long enough to meet the needs of most riders using relatively wide gearing. That means that most riders will probably have to trim off 2-6 links or so. When measuring there are two considerations.
1- the chain must be long enough to loop the two largest sprocket together with an inch to spare. Consider this the absolute minimum length.
2- the chain must be short enough to loop the two smallest with the RD taking up all the slack. There's some fudge room here if necessary, though it's to be avoided.
Most bikes have some latitude between the maximum and minimum and you'll find people adamant about which is the "right" length. IMO, anything between the two is fine, though an experienced mechanic can often improve RD performance by selecting an optimal length between the two. Personally I lean toward using chains close to the longest possible.
To answer the original question.
New chains are usually sold long enough to meet the needs of most riders using relatively wide gearing. That means that most riders will probably have to trim off 2-6 links or so. When measuring there are two considerations.
1- the chain must be long enough to loop the two largest sprocket together with an inch to spare. Consider this the absolute minimum length.
2- the chain must be short enough to loop the two smallest with the RD taking up all the slack. There's some fudge room here if necessary, though it's to be avoided.
Most bikes have some latitude between the maximum and minimum and you'll find people adamant about which is the "right" length. IMO, anything between the two is fine, though an experienced mechanic can often improve RD performance by selecting an optimal length between the two. Personally I lean toward using chains close to the longest possible.
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Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
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FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
