Dampening side cover noise.

GoldenMotor.com

K.i.p

New Member
Nov 8, 2009
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I decided to do a little experimentation and pass this along. My build is torn down and hopefully I will be painting this weekend. Here is what I did to dampen the "forks in the blender".

Needed: cheap latex caulk, plastic wrap, 2 stroke China girl, minimal artistic ability.

I began the process by putting down a layer of caulk to coat the inside of the side cover.

Next I put a sheet of plastic wrap over the motor.

With a little care I seated the cover in place to check for interference impressions in the calk (you'll need to actuate the clutch lever to get an accurate imprint).

After removing the cover I could see the caulk was heavy toward the center of the cover so I used a jar lid to press it out and continued with my fingers and thumbs to form the caulk to better suit the mechanicals. It is easy to manipulate the caulk as it is now under the plastic wrap which should should transfer off the motor and stick to the side cover.

In a final preparation step I actually mounted the cover, plastic film, and caulk to the motor with two screws. I then rotated the clutch shaft while the lever was depressed to squish any remaining caulk out of the way.

After removing the cover I placed everything in the freezer to stiffen the caulk. After an hour or so the plastic wrap peeled out leaving the nicely formed latex in place. I have it curing right now and will have a few days while I paint to let it skin up and start hardening a little. I will test it's effectiveness in a week or so.
 

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2door

Moderator
Staff member
Sep 15, 2008
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K.I.P,
Please let us know how it works for you. My only concern would be the adhesion to the cover. That could make a real mess if the latex comes loose. Keep us informed.
Tom
 

svc

New Member
Jan 10, 2009
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sydney australia
I smeared red silicone gasket over mine months ago, its still holding there fine. I also contact glued some mouse mat on the outside(my bikes not as pretty as most on here lol).
 

K.i.p

New Member
Nov 8, 2009
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Agreed, adhesion is a valid concern. However I have used this stuff around the house and removing it (or caulk in general) can be a chore so I figure I have a good shot at success. I also agree it could cause a mess but not really a damaging one, if it breaks down or comes loose it won't destroy anything, a potential nuisance more than anything else. Time will tell. In retrospect I probably should have scored and roughed up the inside of the case, hindsight is 20/20. I will try to update this in a few weeks, we are still getting out of winter weather here.
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
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northeastern Minnesota
I always have scrap elk hide around from making moccasins. Cut it to size and then adhere it with shoemaker's contact cement (what I use to adhere rubber soles to my mocs. Good stuff.
SB
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
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up north now
I always have scrap elk hide around from making moccasins. Cut it to size and then adhere it with shoemaker's contact cement (what I use to adhere rubber soles to my mocs. Good stuff.
SB
I bet that would be great for using between the mounts and the frame too.
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
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northeastern Minnesota
I bet that would be great for using between the mounts and the frame too.
It is; I glue it directly to the inside of the mounts and do the same anywhere I have to clamp directly to the frame. You can reposition the thing you're clamping without having wrecked the paint. Old leather from a suede jacket and regular contact cement will work as well.
SB
 

K.i.p

New Member
Nov 8, 2009
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I read about the other methods suggested but I wanted to try something "outside the box", if it works or fails I figure the community is better off for my efforts and experimentation.
 

Outrunner

New Member
Dec 27, 2008
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Atlanta, Georgia
Do the same, but use butyl caulking. It will stick to grease!
You can buy pre-cut "viscoelastic butyl rubber noise absorbing pads with self
adhesive backing, from Pirate Cycles, one of our sponsors. It's called JNM Damp-Pro
and the kit sells for $15.00 with 3 pre-cut pads to fit all 3 covers. I use them on my engines,
and it truly works well.
 

bairdco

a guy who makes cool bikes
Aug 18, 2009
6,537
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living the dream in southern california
actually, corgi1, that's not a bad idea.

people use rubberized undercoating spray on the inside of fenders and stuff, and that dampens vibes, but it's a brown runny mess and takes awhile to dry.

the plasti-dip spray dries quick (says 4 hours, but depending on how thick you lay it on, it dries to the touch pretty quick.)

i've used it on fender struts and rear chain stays, other scratch prone areas, and you can't tell the difference between it and the paint.

if you painted a whole bike with it, besides the added weight (which doesn't seem to matter much anyway on a cruiser) you'd have a durable, almost scratch proof bike.

and they make a clear, too. i'm gonna pick some up for my next bike.
 

stuartracing

New Member
Dec 9, 2008
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Gainesville FL.
I just got done putting dampening hose in between ALL the cooling fins on the motor.....I used some clear hose from Lowes and just cut 1" lengths and stuffed them in to the cooling fins.....It really cuts down on the vibrations quit a bit IMO......Gonna try the caulking idea too....
 

K.i.p

New Member
Nov 8, 2009
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Thanks for the tip and leap of faith. Please post your results as I am curious how this might work for others. I'm excited to listen after I get everything put back together! I remain pretty optimistic.
 

K.i.p

New Member
Nov 8, 2009
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I took my first run since everything has been painted and reassembled. The clatter and rattle from the drive gears was barely audible. Now it only remains to be seen how durable this is. I did observe some shrinking of the caulk as it cured over the last week or so but it did not seem to be pulling away from the cover. So far so good.
 

Tim_B_172

New Member
Aug 26, 2009
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Saint Joseph, MO
Neat idea. I've often been annoyed by the gear noise, but never really gave any thought to eliminating. About how thick is you're layer of caulk at it's thinnest point? I'm wondering if you couldn't just spread a thin layer out evenly with a putty knife and get the same results without having to do the thing with the plastic wrap.