SWM tl320 shock mounting positions

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Reinald
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SWM tl320 shock mounting positions

Post by Reinald »

G'day,
Was having a a general look around on the bike the other night and found that the threaded eyelet where the shock [falcon] is bolted to the swing arm was loose on one side. [It was suggested by a mate that this could be spot welded via MIG to repair.]

No worries, the SWM has 2 mounting positions, so I took some longer hex head bolts and some penny washers [existing cup head/allen bolts were two short as the forward mounting position has nuts welded on rather than threaded eyelets] and can ride again.

My question is what effect does the forward mounts [20 mm] have on the spring rate and damping [stiffer I'm guessing] and steering geometry [sharper?] and it looks like I've gained some ground clearance?

2nd question are penny washers OK instead of cup washers in terms of clearance to the rubber shock bush? Should I run this a little looser and put a lock nut on the bolt on the inside? or would best bet replace with longer allen bolt and cup washer.

Thanks for any help forthcoming on this matter..... I'm going for a test ride.
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Reinald
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Re: SWM tl320 shock mounting positions

Post by Reinald »

Test ride went well. The new position seems to be a bit firmer and the handling a little bit sharper.
Mark
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David Lahey
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Re: SWM tl320 shock mounting positions

Post by David Lahey »

Falcons need to be mounted in a way that avoids putting side loading on the seal. To avoid side loading the seal, both ends of the shockie need to be able to rotate on their mounts freely as the suspension moves.
One way to provide for the shockies rotating without side loading the seals is to use loctite on the retaining screws and tighten them just eoungh to remove free play, but not enough to grip the shockie rubber.
As far as the different mounting position goes, if the shockie is moved closer to the pivot the springing and damping action will be softer and the wheel travel will be greater. 20mm forwards on the lower mount should make a noticable difference.
As for the effect on steering and ground clearance, the height and attitude of the bike with you aboard is what matters.
relax, nothing is under control
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Reinald
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Joined: Wed Sep 09, 2009 11:57 pm
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Bike: SWM TL320 1982
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Re: SWM tl320 shock mounting positions

Post by Reinald »

Thanks Dave,
Maybe the better action on the back is more travel not firmer.....it feels better.
Thanks for the advice on shock bolts.
I'd rather be a D grade participant than an A grade spectator....
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