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Singlespeed Problem
 

[Closed] Singlespeed Problem

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[#5585629]

I have just purchased sliding dropouts for my commencal Absolut SX....

Spot the obvious problem.......

The caliper mounts are fixed (not slotted like most designs)- so how am I supposed to align the calliper to the rotor when I tension the chain?

My thoughts are - you don't, the wheel can only be located in the middle of the dropout.

This brings me nicely to the next point - why do sliding dropouts exist at all for this frame - and why have I just bought some?!!


 
Posted : 09/10/2013 10:45 am
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That looks like a full suss frame. Unless the swing arm pivot is concentric with the bottom bracket the chain tension will vary as the suspension moves. This could lead to either a snapped chain or something much more expensive. Beware.


 
Posted : 09/10/2013 10:49 am
 Sam
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There probably is some margin for adjustment as the brake caliper will sit pretty much at the top of the disc, so a little movement back and fork will likely be OK, just double check that all of the pad is contacting the rotor. Less than ideal though.


 
Posted : 09/10/2013 10:49 am
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Mostly Balanced

It is concentric


 
Posted : 09/10/2013 10:50 am
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what Sam said - you'll have a bit of fore and aft movement whilst the pads are still ok on the disk. I'd look at using a half link if you need to keep the hub pretty much in the right place, though.


 
Posted : 09/10/2013 10:52 am
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Half link - good idea!


 
Posted : 09/10/2013 10:54 am
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It is concentric

While you were typing that I was googling images to check.


 
Posted : 09/10/2013 10:55 am
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similar set up on old dmr frames and the like, I always ran what ever size disc kept the caliper/pad parallel with the dropout and the half link sounds like a good idea too that way you only need 1/4 of an inch movement


 
Posted : 09/10/2013 10:59 am
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Sounds like it can be made to work
Does jacking up the caliper a bit with shims help at all?
Do people suffer uneven pad wear if you cant get the whole of the pad on the rotor?

I'm just generally a bit miffed about the lack of thought gone into the design of this - accentuated by the horrific cost of the dropouts ๐Ÿ™


 
Posted : 09/10/2013 11:10 am
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....specialized look like they have managed it with there new design though....

http://www.pinkbike.com/news/Specialized-Debuts-Dual---Suspension-Slopestyle-Bike-at-Crankworx.html


 
Posted : 09/10/2013 11:13 am