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[Closed] First full suspension build - how do I determine chain length?

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[#3317566]

Hi I'm building up a Giant Trance X frameset and it's my first full sus build.

I've built a few handrails and done big front and rear and not through mech then added 2 links, but how does it work with rear suspension?

Cheers guys any help/advice greatly appreciated.


 
Posted : 04/11/2011 6:50 pm
 5lab
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same way, but drop out\unbolt the shock to figure out the position where the "chainstay" is at its longest, then add 2 links


 
Posted : 04/11/2011 6:51 pm
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let all the air out of the shock and compress it. cable tie the bottom of the rear mech to the chainstay and thread it through big big.


 
Posted : 04/11/2011 6:57 pm
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This is me being dumb but what does cable tying the rear mech to the chainstays achieve?

I'm not running the chain through it right?


 
Posted : 27/11/2011 12:53 am
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LOL at thepodge


 
Posted : 27/11/2011 12:56 am
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you undo the cable tie after you've threaded the chain through and rejoined the chain, it just acts to keep the mech from springing back. means you only need two hands to do the job not three.

reuseable cable ties are everyones best friend


 
Posted : 27/11/2011 1:33 pm
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If I'm not running the chain through the mech why would it spring back and not just sit there happily?


 
Posted : 27/11/2011 4:48 pm
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because that's how the spring works.

more importantly why aren't you threading the chain through.

I think we've missed something somewhere between us


 
Posted : 27/11/2011 4:56 pm
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I have never done anything with the rear shock on any of my full suspension bikes and just measured the chain big-big + two links (without threading the chain through the rear derailleur), like you would on a hardtail. I haven't had any problems whatsoever doing this.


 
Posted : 27/11/2011 5:02 pm
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Podge I thought it was big to big but not through the rear mech?


 
Posted : 27/11/2011 5:26 pm
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It is.


 
Posted : 27/11/2011 5:27 pm
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I did mine the big-big (not using the rear mech) plus 2 links way and it's been spot on.

No idea what thepodge is on about he's lost me.


 
Posted : 27/11/2011 5:32 pm
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I just watched a video and he thread it through the mech but only outside the cogs.

Ill definitely let the air out and compress the shock and go big big, unsure from there though.


 
Posted : 27/11/2011 5:34 pm
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I'll try that cheers Neninja.

Podge cheers for the help by the way


 
Posted : 27/11/2011 5:35 pm
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why go big big not through the mech then add two links then thread it through the mech?

why not just thread it through in the first place?

what I do is let all the air out of the shock, cable tie the bottom of the mech to the chain stay, thread the chain where its supposed to go, remove excess links and rejoin the chain, undo cable tie, put air in shock.

chain goes on the bike once, no need to take it off and refit it.


 
Posted : 27/11/2011 6:19 pm
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Cheers Podge I'll give that a try tonight


 
Posted : 27/11/2011 8:00 pm
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why not just thread it through in the first place?

Isn't it because measuring the chain outside of the derailleur results in the correct tension on the derailleur? If you measure it with the chain through the derailleur you can pull the chain either too much or not enough, resulting in poor tension.

I Note your comment about using a zip tie, but that sounds more fiddly and may still result in poor tension as I'm sure the mech isn't held that fast.


 
Posted : 27/11/2011 8:13 pm
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Jeez, just build the bike up, put the chain on small/small going though the mech as normal. If the mech can't take all the slack then take a link off until it does.


 
Posted : 27/11/2011 8:48 pm