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[Closed] How exactly are sloppy fork bushes " resized " rather than replaced ?

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[#3231702]

never seen it explained , can't find the answer by googling ..is it a trade secret?. I am intrigued to know . I suspect it's done by re positioning the bush inside the lowers. people have suggested a slight tapering inside would allow this but then surely they wouldn't sit flush with the stanchion and there'd be more clearance at one end than the other. Also if repositioned what stops them moving about ?
someone in the know spill the beans please ! LOCO ?????


 
Posted : 10/10/2011 9:33 pm
 Del
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believe the interior of the lower is tapered as you think. if the exterior of the bush is tapered too you'd get a uniform fit. there'd only have to be less resistance on the interior of the bush/upper interface ( which is, after all, supposed to move with little friction ), for the bush itself to stay put in the lower.

*not an expert though*


 
Posted : 10/10/2011 9:39 pm
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EH? are you sure that resized dosent simply mean replaced with a thicker bushing to remove the play? You can't simply resize a bush.


 
Posted : 10/10/2011 9:47 pm
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Well if that's how they are fitted how are they sized? People talk about sizing them specifically for a particular set of uppers. How do they measure if the bushings are pushed in the right amount when in there?


 
Posted : 10/10/2011 9:49 pm
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I used to do Marzocchi bushes by putting a little shim steel behind them. Worked a treat.


 
Posted : 10/10/2011 9:49 pm
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I do wonder whether it may be a simple matter of tapping the bush one way or the other and the companies keep it quiet because of what they charge ! Pure conjecture on my part though


 
Posted : 10/10/2011 10:01 pm
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http://vmaxoutlaw.com/tech/fork_stiction_tuning.htm

Try that. Basically wet n dry um.


 
Posted : 10/10/2011 10:44 pm
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Pricing up the seating/removal tool will give you an idea of why they charge so much.


 
Posted : 11/10/2011 8:33 am
 LoCo
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Morning, depending on the fork the bushes can be moved to increase or decrease how tight they are.
Most forks will have a shoulder that the bushes will sit against which I don't push the bush past as this, as mentioned above would cause the bush to taper and is a bit of a bodge.
Fitting of new bushes is pretty cheap considering the amount of labour that can be involved and the cost of the bush kit in the first place, after they're fitted they need to be sized to match the stantions too, again need ing more exspensive tooling and time, to get them just right.

The link above does cover it roughly, but I certainly wouldn't remove and pin puch the back of the bushes to close them up and then refit, bit bodgey again and time consuming, you'd be far better to fit some nice new smooth and clean bushes.


 
Posted : 11/10/2011 9:15 am
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Also, how much play is classed as ok?

On the third set of replacement Marzocchi 44's and brand new out of the box I can hold the lower in one hand and the steerer in the other and get a little movement/knocking. Given that they are brand new and I got them as the bushings seemed to fail totally on the others (one ride after the uppers were replaced under warranty), should they have any play at all?

Compared to a set of 2005 Rockshox Pikes which have only just developed play the new Bombers have more play.


 
Posted : 11/10/2011 9:23 am
 LoCo
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Without feeling the forks it's difficult to say, different manufacturers' tollerances will vary. Can you feel the movement when riding? and have you stored the bike upside down to lube the upper bushes as there should be a layer of oil between the stantion and bush which will also reduce movement and increase 'plushness'


 
Posted : 11/10/2011 9:26 am
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LoCo, not fitted them yet, just got them back.

Bought forks about 8 weeks ago, fine for 4 rides then started creaking badly, returned under warranty and uppers replaced. Rode for one short ride and developed loads of play (felt like the front of the bike was falling off), returned again under warranty, lowers found to be faulty and full new set of forks sent.

Just worried I'm gonna fit them, have a couple of rides then have to start the returns process all over again.


 
Posted : 11/10/2011 9:30 am
 LoCo
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See how they go, third time lucky! ๐Ÿ˜€


 
Posted : 11/10/2011 9:49 am
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Hope so.

Will never buy marzocchi again, was seduced by their claims of improved reliability but the proof is not in the pudding.


 
Posted : 11/10/2011 10:18 am