How to: Kill Your Buzz (4k RPM Fairing Vibration repair)

How-to's for the Seca II's cosmetics, including detailing, paint, bodywork, fairings and seat reupholstry
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[center]How to: Kill Your Buzz
Stop that 4k-5k RPM Fairing Vibration
Originally posted by Cityevader
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As promised, here are some techniques to eliminate 95% of typical Seca II buzzes, rattles, and vibration:

First (hardest) of the easy steps is to weigh down the handle bar. My hands get kinda numb after awhile with vibration. Whether a motorcycle or powertools. So I filled the bar with metal. 13oz to be exact. Go to any car repair place that does brakes, and ask for a couple handfuls of metal "sawdust" from the brake lathe. Obviously you want only the shavings and not any trash that usually ends up in it as well.

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Go to the hardware store and get two rubber "corks". Get one size bigger than the inside diameter of the handlebar....I believe it was 3/4", but threw away the package.

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Remove handlebar. Or, as I was working on the carbs and there was no gas in it, I just laid the whole bike over on its side to fill the bar.
Clean the inside of the handlebar with brake clean or aolcohol and let dry. Apply a small amount (or may damage rubber) of brake clean to the cork to lube/soften and in one smooth motion without stopping, use something like a large phillips screwdriver as I did, or dowel, to ram it into the handle bar about 2 to 2.5 inches. Allow enough depth for bar-end mirrors or weights. Important, plug the throttle side first, otherwise you risk shavings spilling in between bar and throttle! For additional security, I added a bunch of hot melt glue to further plug the plug.

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Flip the bike/handle bar over and use a funnel to pour shavings into bar. Note: the shavings will not "self-level" like ball bearings. They interlock and will "clot", so repeatedly smack handlebar with piece of wood during the pour to settle the shavings. Again, stop about three inches or so from end, allowing room for plug and possible bar-end accessories.
I wish I had taken a picture of the next step of plugging. In order to not compress air inside of bar, one must insert a length of thin plastic straw from aeresol can, such as brake clean. Insert it almost to the metal shavings and hold it there while ramming the rubber plug in. This will allow a path for air to escape. Once the plug is firmly seated, pull out the straw. If desired, backfill with hot-melt glue for further assurance.

This has completely eliminated tingly hands for me. The mirrors (at least my one good one) are rock-steady. The bad mirror went from 100% no good to almost fully useable (-100% to +70%). One can clearly behind them now. Since this isn't a race bike, I say "big whoop" to the weight gain. I've gained 40 times that amount in body weight!


Next, get/borrow a heat gun, and acquire some "Dynamat" deadener from nearly any car audio shop. Dynamat is a brand, but used like "Kleenex" is, to generically refer to asphalt-based adhesive-backed heat-activated sheets of approx 1/8" thickness. It reduces the panels' resonating and acting like a speaker. The larger the panel, the louder the radiating surface for noise. Adding mass dampens those resonations. There are many names/ configurations/sizes/etc of this material....pick one.
Then, strip all plastic off to get naked. Lay them paint-down on carpeting or blankets or whatever, and thoroughly clean the inside, dirty side, then rub down with alcohol and let dry. Now the fun part! Cut the sheets/rolls to fit. My first Seca I had a large sheet already, so I covered the entire inside surface of fairing. This is uneccessary. The deadening qualities will work just fine in only the wide-open parts between mounting points are covered. For this Seca, I had only a small amount leftover from years ago, and this is still plenty of coverage. Apply heat to soften the material and work in about a 6" square at a time, using a gloved hand to form it to contours. Avoid working from the "outside-in" as this will create air pockets. Just slice the pockets with a razor and reheat/press it down. Repeat process for all fairing panels.
I then sprayed undercoated over the remaining surfaces just because I had a can I never used. I don't really recommend this. It's messy and stays kinda soft and you'll get sticky fingerprints everywhere.

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While the bike is naked, look to see where the fairings have been rubbing. Paint worn off from contact is a "witness mark" Trim a bit of plastic off the fairing to eliminate contact. In the following pic, the half-circle portion of the fairing used to contact the frame, and picture was taken after trimming. There will be many areas like this, so look carefully.

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There will be many spots like this, around the headlight, side panels against frame, etc... trim away as much as is feasible.
Then, everywhere there was foam tape applied, add another layer, such as this curved section of seat panel against the frame.

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There is one spot of seat trim that has no foam tape, and needs to be added. The front corner below the tank. It is visible, but minor enough to not bother me. You only see it if you're looking. Others may be more anal about appearances than I am. If so, don't add foam and rattle away.
Don't forget to cover all over the headlamp so soften the contact area between it and fairing.

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Finally, go after physically moving parts that bang against each other. The worst offenders up front are the speedo cable near the headlight adjuster. Zit-tie it securely to prevent rattling. Second worst is the horizontal headlight adjuster. Apply some foam tape there as well.

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Now go all over the bike securing wire harness to the frame. You can tell where they've been moving as paint will be rubbed through, often to bare metal. If so, seal with a shot of spray paint of similar color to prevent rust, then zip-tie harnesses to prevent movement against frame... Look everywhere for these sneaky offenders.

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You get the idea. The above are just a taste of the many spots. A word of caution: When zip-tying cables/wiring around the front area, moving the handlebars side to side to ensure no stretching of things zip-tied to clutch or throttle cables, etc. The cables themselves cannot be secured to the body, but CAN be wrapped in foam tape where they contact.

Now, the final step. With the foam tape around the headlight, the front fairing may fit differently, so mount it up and make sure all the bolts line up. Remove the rubber bumper from near the front of the valve cover area of frame and use a pick or something to scribe the hole. I found out after struggling with going from underneath, that there is tons of access from the top. Repeat for other side and remove fairing again. Now go to the hardware store and get some 8-32 welnuts and bolts. Or if you have leftover metric ones from fairings/windscreen, then use them.

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With the fairing off the bike, drill out the fairing to about 3/16 or so for an 8-32 bolt to fit loosely through. Then drill the frame so that the wellnut fits in. Don't drill it too big. I did it slightly smaller and filed it the rest of the way. Mount the fairing back up and now the lower portion is secured with a bolt to prevent it from banging away against the bumper. You can paint the screw head, or match them with the fairing screws, or just leave them as I did.
The end result of all these steps is a super-smooth sounding, solid-feeling bike that doesn't sound like a can of loose bolts!

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