How to Check Vibration Damper?

comet · Post by **comet** » Sun Nov 19, 2006 8:03 pm

Kurt; That circular black thing in the R69S dampener made of unknown material has always been a problem, they deteriorate on the shelf. The large disc when tightened down should be able to be rotated. The sholder on the front metal piece should bottom out on the small sholdered piece on the other end, preventing pinching. You should have a total of 8 pieces. Many owners run without any damper, using the R60 bolt. I would rather run without one than with one that is off center...Comet

schrader7032 · Post by **schrader7032** » Mon Nov 20, 2006 7:27 am

Thanks, Comet. I have all the pieces and a new rubber piece which is still in good shape. I took it apart this weekend for inspection. However, I am unable to rotate the damper relative to the engine. When I grab the steel disk and turn it, the engine turns also. There doesn't seem to be any relative motion with the damper. I'm inclined to run without it. I had heard of using the shorter bolt...or maybe I can stack up some washers/spacers to take up the space.

Kurt in S.A.

comet · Post by **comet** » Mon Nov 20, 2006 9:46 pm

If the large disc seems centered I would run it for a while then take a look at it. I can't imagine that a non rotating disc could be much of a problem, it tells me that the rubber is a little full that's all................Comet

Allan.Atherton · Post by **Allan.Atherton** » Tue Nov 21, 2006 9:54 pm

... I have all the pieces and a new rubber piece which is still in good shape.... However, I am unable to rotate the damper relative to the engine. When I grab the steel disk and turn it, the engine turns also. There doesn't seem to be any relative motion with the damper....
There shouldn't be. It needs to be tight or the rubber will get torn up quickly.
Don't trust the old rubber. Get a couple of new rubbers from Bench Mark Works and carry one as a spare. I put one of their rubbers in back in 2001 and after 10,000 miles it is still good and tight. Someone else has almost 20,000 miles.

Allan.Atherton · Post by **Allan.Atherton** » Tue Nov 21, 2006 9:58 pm

... I had heard of using the shorter bolt...or maybe I can stack up some washers/spacers to take up the space.
I don't understand where you would stack washers. You could use the damper bolt and hub without the damper parts, or you could use an R60/2 generator bolt. But I would use the whole damper.

VBMWMO · Post by **VBMWMO** » Mon Feb 15, 2010 2:51 pm

I might as well cross-post this wherever I can

I replaced the rubber damper part in mine about 1000 miles ago, which is not quite 2 years...got it from Vech. The original one that was on the bike had turned to a gooey mess. There was evidence inside the front cover of circular black rings as the steel disk was spinning the goo off. I have less than 100 miles on my engine rebuild and notice that black rings are
beginning to show up again inside the front cover. I had cleaned
everything spotless as part of the rebuild.

I managed to find this again (I forgot where it was):

http://www.beemergarage.com/documents/228.pdf

It says that it should rotate on the hub. If it moves easily or if it moves laterally, the damper is not working right. The times I've tried to check mine, I can't move it at all. The bolt that ties everything together onto the generator rotor is typically put on fairly tight. I'm fairly sure that I have all the right pieces.

Mine does not move at all. Does that mean that the clamp up is too
tight and squeezing everything together too much? Any idea why the vibration rubber is giving up the ghost so quickly? How do I determine if mine is still working or not?

Kurt in S.A.

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