What are these plugs for?

[ToddStyles]

What are these black plugs on the cylinder head used for? Here's a pic:



just curious.
Thanks,
Todd.

[bonanzadave]

This is only a guess. Vibration dampening.

[t3rmin]

I've heard it's to strengthen the fins. I'm missing a few myself but it's no big deal.

[jpaul]

They are for vibration dampening. I picked up an added sound on my 82 when they finally fell out. Not a lot of noise, but after 15 years I noticed the change in sound immediately.

[brveagle]

They are for strength for the fins. They add some support to help them from breaking off.

[denydog]

I'll go with vibration damping (noise reduction)

I think they might actually reduce strength of the fins due to the cutout in the fins to accomodate the rubbers.

[Boondocks]

The rubber pads reduce noise by damping vibration. They prevent the aluminum fins from "ringing" like a bell.

[Nessism]

I'll go with vibration damping (noise reduction)

Thank you for using the proper term "Damping" not "Dampening".

Funny, even Suzuki writes dampening in the service manuals sometimes.

[t3rmin]

I'm having a hard time imagining how those plugs could reduce vibration. They're embedded in a completely solid block of metal and they don't have much mass...

[Guy]

Well don't burn your brain out trying to imagine....Like boondocks says: They prevent the fins from ringing like a bell. Thats what they're for. Nothing else.

[J_C]

With the rubber pads at $2.50 each, my fins can ring like a bell :-D

[nert]

where did you see them for sale? I have not seen them on Bike Bandit OE parts, or any where else..
I would buy them.
Not fond of metalic noises, (distraction), even if they are innocent. Quite is good, so i can listen for the really scarry noises.

[J_C]

I saw them on the alpha sports site. But they could be model specific... don't know.

[t3rmin]

So we're not talking shake-your-butt vibration, just audible resonance of some kind? I *can* imagine (ow! my brain! ;-)) the plugs damping a bell-like sound...

[Boondocks]

Thank you for using the proper term "Damping" not "Dampening".

Funny, even Suzuki writes dampening in the service manuals sometimes.

Right, dampening is what can happen to your underwear after a close call.:-D

where did you see them for sale? I have not seen them on Bike Bandit OE parts, or any where else..
I would buy them.
Not fond of metalic noises, (distraction), even if they are innocent. Quite is good, so i can listen for the really scarry noises.

The best prices for these pads seem to be at Flat Out Motorcycles.

For my bike, the 16 pads are $1.47 each. The 1980 GS1100E changed the cylinder head configuration at a certain serial number, and the pads would be different depending on the bike's serial number. My point is, the pads are likely to have variations for each engine and model year.

Look them up in the fiche by "Cylinder Head", and they will be described as "Pad, Rubber or Pad, Cylinder Head Rubber, or Rubber Pad".