offset bushing inst...
 

[Closed] offset bushing installation

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I can't find where I purchased my offset bushings from, can anyone recall- for slacker head angle is it both bushing holes to the inside ? outside ? both in different directions ?

I've got both pointing in towards the shock at the moment and I think that has steepend head angle...but its a new build so don't know default without the bushings.
Cheers.


 
Posted : 30/01/2013 11:27 am
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pointing towards the shock body to shorten the i2i


 
Posted : 30/01/2013 11:32 am
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are you not an engineer!!


 
Posted : 30/01/2013 11:33 am
 LoCo
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Holes shock side, not frame side as you want to effectivly make the shock eye to eye shorter, which is like making the shock sit further into it's travel.


 
Posted : 30/01/2013 11:34 am
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With the holes at the shock end the bike will be lower/slacker.

Just remember to check that it will all work and not bottom out the tyre/linkages/frame before the shock.

its a new build so don't know default without the bushings.

Being facetious; how do you know it needs to be lower/slacker then? compared to the designers oppinion who presumably actualy rode it and decided it was about right?


 
Posted : 30/01/2013 11:34 am
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opposite? ๐Ÿ˜‰


 
Posted : 30/01/2013 11:34 am
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Just done this on my frame. Both holes on bushes facing inwards on the shock


 
Posted : 30/01/2013 11:34 am
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Being facetious; how do you know it needs to be lower/slacker then? compared to the designers oppinion who presumably actualy rode it and decided it was about right?

Slacker is BETTERer!! I actually got a longer shock for my heckler to steepen in up a bit (after putting longer forks one it)


 
Posted : 30/01/2013 11:36 am
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Great thanks. So correctly installed at moment. Cheers.

mmmm, maybe my inclinometer isn't up to scratch, El Guapo, getting 70 degrees with the bushes installed with Marzocchi 44 150, 2.4 Rubber queen tyre and Super star external Headset... was expecting much slacker.


 
Posted : 30/01/2013 11:46 am
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try putting the measuring device down and riding the damm thing.


 
Posted : 30/01/2013 11:52 am
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o good god.


 
Posted : 30/01/2013 12:25 pm
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I fitted some and then they started squeaking so i took them off.

๐Ÿ˜ฏ


 
Posted : 30/01/2013 12:28 pm
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oooh dear 70 degrees ๐Ÿ™

otb


 
Posted : 30/01/2013 12:30 pm
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I should keep out of this one! ๐Ÿ˜ณ
But holes facing shock or inwards.


 
Posted : 30/01/2013 12:57 pm
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honestly its 1 facing in 1 facing out ๐Ÿ™„


 
Posted : 30/01/2013 1:02 pm
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slow day ?


 
Posted : 30/01/2013 1:06 pm
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tut tut, I shoulda searched first...

http://singletrackworld.com/forum/topic/offset-bushings-must-be-a-trade-off-reduced-rear-travel/page/2


 
Posted : 30/01/2013 1:18 pm
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Has anyone who has fitted them both facing towards (or indeed both facing away from) the shock had a look at them recently?

Assuming the bushing (and by bushing, I mean the little hula hoop bit which is either cream coloured plastic or a thin band of metal with a coating on the inside) is supposed to [b]rotate[/b] around the mounts (the actual 'offset' drilled part), then the offset bushing kit should find its own position, non?

The more you bounce on the bike, the more the offset mount(s) will want to migrate round the shock bolt and the inside of the bushing until the hole that the bolt goes through is as far away from the direction of the forces compressing the shock as possible. Therefore if you look at the driveside of the bike (and the shock itself is mounted roughly horizontal not vertical), then both mounts should eventually migrate to three o'clock.

Anyone who has seen an improperly tightened eccentric bottom bracket try and move itself to the three o clock position under pedalling should understand what I am getting at: like an EBB you need some way of clamping the offset bushing mounts in place if you want them to stay put in any other position, and I am not sure a single m8 bolt is up to that...


 
Posted : 30/01/2013 1:59 pm
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Not sure you've quite thought that through, the shock has all of the forces in compression (unlikely the rear triangle would ever be pulling it appart), so the bushes will migrate towards reducing the eye to eye length, i.e slackening the bike.

And why would you put them both in the same direction? That will have almost no effect (might afect leverage slightly at he begining/end, but unlikely the bikes geometry). You either want the eye to eye increaced or reduced.

And surely an EBB will move to about 8:00 (looking from the drive side). The chain tension is the biggest force (so moving it to about 9:00) folowed by the riders force (pushing it down slightly). I usualy aim for about 2:00 when adjusting mine so that the forces aproximately ballance.


 
Posted : 30/01/2013 2:21 pm
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mikewsmith - try putting the measuring device down and riding the damm thing.

Mike, guess what. Checking these things are important. First ride last night and I was ****ting pedals on every rock on flat ground.

Turns out my EG frame has been built wrongly, and the BB is 20mm to low...

so worth checking your bike before you go out and fling yourself down a rocky hill.


 
Posted : 01/02/2013 12:14 pm