Author Topic: function of Jug fin pucks  (Read 1159 times)

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Offline johnyvilla

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function of Jug fin pucks
« on: July 24, 2009, 05:27:36 AM »
I am about to have my jugs media blasted and I was wondering if I should remove those rubber pucks, (for lack of a better term) from between the fins.

Why are they there anyway?

Offline mystic_1

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Re: function of Jug fin pucks
« Reply #1 on: July 24, 2009, 05:32:37 AM »
They're supposed to keep the fins from vibrating at the resonance frequency of the engine.

Later engines omitted them completely.  I'd remove them for media blasting, but they'll tear on the way out and replacements are expensive so plan on running without them unless you're a restoration purist.

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Offline markb

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Re: function of Jug fin pucks
« Reply #2 on: July 24, 2009, 05:53:02 AM »
Yea they're expensive ($3 apiece) and the only replacement ones I've been able to find are black, not the original color.  Sometimes if they're not too hard you can get them out without tearing.  I've got a bunch I've scrounged and one of these days I'll pick the best ones and reinstall them unless someone knows a source for the original color.  Otherwise I wouldn't replace them either.
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Offline johnyvilla

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Re: function of Jug fin pucks
« Reply #3 on: July 24, 2009, 05:57:01 AM »
Well if they omitted them, I don't need them.
Thanks

Offline lordmoonpie

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Re: function of Jug fin pucks
« Reply #4 on: July 24, 2009, 08:03:24 AM »
I left mine in for blasting and didn't lose a single one of them. Be sure you want to take them out- that resonance creates extra noise. Extra noise needs energy to create it so you end up with a noisy powerloss! (well in theory)  ;D
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1951 Ducati 50cc Cucciolo
1981 Yamaha XV750 SE