Author Topic: cylinder fin rubber seperators- what are they for?  (Read 1223 times)

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Offline greasy j

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cylinder fin rubber seperators- what are they for?
« on: March 28, 2010, 02:49:56 PM »


any one know what these do exactly? I know I've seen lots of engines without them, so they can't be super critical. these came stock, right?

if they are helpful somehow, anyone know of a good easy replacement. I could get a bunch of pencil erasers and cut nipple shapes in them. :P

I'm sure they'll be left out of the rebuild, though. unless you guys can give me a reason...

Offline plastikjock

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Re: cylinder fin rubber seperators- what are they for?
« Reply #1 on: March 28, 2010, 03:05:40 PM »
I think it's to absorb noise, sure I read it some where.

 :)

Markcb750

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Re: cylinder fin rubber seperators- what are they for?
« Reply #2 on: March 28, 2010, 03:10:26 PM »
they dampen vibrations from the engine movements reducing the tuning fork effect of the fins.

Could just be Honda did not want the motor to sound like Yamaha's logo... ::)

Offline Alan F.

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Re: cylinder fin rubber seperators- what are they for?
« Reply #3 on: March 28, 2010, 04:35:49 PM »
OK, here's my thread hijack question, is there something one can use in place of these dampeners if you haven't got them? They're almost $5 each new....

Markcb750

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Re: cylinder fin rubber seperators- what are they for?
« Reply #4 on: March 28, 2010, 05:11:00 PM »
Not speaking from experience but something like this; Viton Oring material,  might work well. *400 Deg F 


The adhesive would be important.  O ring materials respond well to Cyanoacrylate based glues, but how well it would bond to the aluminum would need testing.
« Last Edit: March 28, 2010, 05:54:57 PM by Markcb750 »

Offline Alan F.

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« Last Edit: March 28, 2010, 05:53:18 PM by Alan F. »

Offline Brown Bomber

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Re: cylinder fin rubber seperators- what are they for?
« Reply #6 on: March 28, 2010, 05:57:22 PM »
Erasers sound like a good idea, if they can handle the heat.
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Offline Alan F.

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Re: cylinder fin rubber seperators- what are they for?
« Reply #7 on: March 28, 2010, 05:58:45 PM »
Yeah I'd worry about regular pink rubber erasers being up to the task, let alone staying in place, they'd probably melt into a stinky gooey mess.

Offline greasy j

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Re: cylinder fin rubber seperators- what are they for?
« Reply #8 on: March 28, 2010, 06:10:09 PM »
I think you're right. that was just kind of a joke. although the ones I took off were very soft, almost gooey, or else hardened in parts.

how many people are going without them and does it sound cool? :P

Offline Alan F.

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Re: cylinder fin rubber seperators- what are they for?
« Reply #9 on: March 28, 2010, 06:31:02 PM »
I dunno, mine came out all gooey and swelled up.  I think it was the gasket remover spray that did them in.  I have another block somewhere I could scavenge them from but I doubt they're much better than the ones that rolled under my bench last year...

Offline City Boy

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Re: cylinder fin rubber seperators- what are they for?
« Reply #10 on: March 28, 2010, 08:13:04 PM »
Hi greasy.Unless you wish to have the rubber inserts in place for original asthetics,you need not worry about installing new ones.No harm will befall your ears.   Rock On
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Offline 754

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Re: cylinder fin rubber seperators- what are they for?
« Reply #11 on: March 28, 2010, 09:04:27 PM »
I have seen them years ago in gasket sets..

 Maybe Ibco or Vesrah.. ???

 I have a 70 ish hexed 750 head  and barrel, someone drilled thru the fins, tapped them and put 1/4 inch setscrews thu the fins.. :o.... anyone ever see THAT..??
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Offline City Boy

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Re: cylinder fin rubber seperators- what are they for?
« Reply #12 on: March 28, 2010, 09:11:10 PM »
Hi 754.Why the hell they do that?    Rock On
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Offline bryanj

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Re: cylinder fin rubber seperators- what are they for?
« Reply #13 on: March 29, 2010, 09:23:00 AM »
Youre right you used to get them in the Vesrah sets but not any more i think
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Offline greasy j

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Re: cylinder fin rubber seperators- what are they for?
« Reply #14 on: March 29, 2010, 09:50:48 AM »
thanks you guys! still the best site ever.

Offline mystic_1

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Re: cylinder fin rubber seperators- what are they for?
« Reply #15 on: March 29, 2010, 12:18:47 PM »
The cylinder fin rubber separators are designed to allow you to rapidly drain your wallet during a rebuild.

  ;)

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