Chain length measurement

[Iainj837]

Does anyone know what the chain line measurement is in a trek rail 9 gen 3 ??

Tia

 

[cyberknight]

Does anyone know what the chain line measurement is in a trek rail 9 gen 3 ??

Tia

depends if you have the stock cassette for a start as different size gears affect chain length

 

[rydabent]

There are too many variables to give an exact answer. Just go with the big big rings, and have a little slack in your derailer.

 

[presta]

Is this a thread about chain length or chain line?

And if it's chain length, are we talking about the number of links required, or measuring wear?

 

[tyred]

Isn't it approx 8 inches in a link and 100 links in a chain and a chain is 22 yards?

But seriously, what I do is to wrap the chain around the big/ big combination without putting it around the derailleur, and then add an extra link. Seems to work fine.

 

[cougie uk]

If I'm replacing a chain I just line it up next to the old one. Amazing how much difference chain wear makes.

 

[presta]

Chainline:

Cutting a chain to length:

Measuring wear:
Use a steel rule.

 

[Paulus]

If I'm replacing a chain I just line it up next to the old one. Amazing how much difference chain wear makes.

That's what I do.

 

[Marchrider]

Chainline:

View attachment 761538

this is new to me -
so how do I compare this to the position of the cassette / I'm guessing from the centre of the wheel to the centre of the cassette, ? these two measurements should be equal ?

 

[presta]

this is new to me -
so how do I compare this to the position of the cassette / I'm guessing from the centre of the wheel to the centre of the cassette, ? these two measurements should be equal ?

Shimano have taken the specifications for my components down from the website in the 17 years since I bought my transmission, and none of the instructions that came with the parts say anything about chainline. I think it's mainly about making sure that the chainset, bottom bracket and derailleur are all compatible with each other, I don't think the chainline for hubs & sprockets is defined because the difference in the standards only amounts to a change in angle of about half a degree.