Author Topic: 5000 RPM HIGHWAY BUZZ IN HANDLEBARS  (Read 6283 times)

Offline shoebox1.1

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5000 RPM HIGHWAY BUZZ IN HANDLEBARS
« on: August 06, 2015, 12:16:54 PM »
4000 RPM AT 60MPH is glass smooth.. kick it up to 5k plus on my 87 k75s and the bars get quite buzzy.. having to shake rhe hands quite a bit,  can i fill the bars with shot or silicone etc?
  • mckinney texas
  • 87 k75s

Offline rbm

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Re: 5000 RPM HIGHWAY BUZZ IN HANDLEBARS
« Reply #1 on: August 06, 2015, 07:25:24 PM »
K75s should be smooth throughout their power range.  If it's buzzing, check TB sync or look for air leaks in the intake system.  Filling the bars with shot is a band-aid that masks the symptoms without solving the root cause.
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Toronto, Ontario

1987 K75 - Build Blog @http://k75retro.blogspot.ca/

Offline TX brick

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Re: 5000 RPM HIGHWAY BUZZ IN HANDLEBARS
« Reply #2 on: August 06, 2015, 10:30:56 PM »
Check the two bolts that hold the muffler at the rear. Mine were loose when I bought the bike and it would put my hands to sleep until I tightened them.
Ron

91 K75RT

Belton Tx

Offline shoebox1.1

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Re: 5000 RPM HIGHWAY BUZZ IN HANDLEBARS
« Reply #3 on: August 07, 2015, 08:16:27 AM »
Ok great! I'll check those bolts.  Thanks
  • mckinney texas
  • 87 k75s

Offline K75RT Keith

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Re: 5000 RPM HIGHWAY BUZZ IN HANDLEBARS
« Reply #4 on: August 07, 2015, 10:22:47 AM »
An exhaust leak at the connection between the collector and muffler can also cause your problem. 

Check for the isolation pad between the muffler mount and frame that small piece of rubbery material makes a big difference.
You can't help someone who doesn't want to hear the answer.

1990 K75RT

Offline shoebox1.1

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Re: 5000 RPM HIGHWAY BUZZ IN HANDLEBARS
« Reply #5 on: August 07, 2015, 11:27:58 AM »
Great! I can't wait to get home and check it
  • mckinney texas
  • 87 k75s

Offline K75RT Keith

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Re: 5000 RPM HIGHWAY BUZZ IN HANDLEBARS
« Reply #6 on: August 09, 2015, 10:29:36 AM »
Had a talk with a older BMW master technician who knows K bikes. He said you're going to get some buzz somewhere in the power band even in the 3 cylinder K75. It is the nature of a piston powered internal combustion engine. Anything that is loose, air leaks, out of balance throttle bodies, etc. will exacerbate the buzz.
You can't help someone who doesn't want to hear the answer.

1990 K75RT

Offline johnny

  • TrailBrakingThrottleWhacker
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Re: 5000 RPM HIGHWAY BUZZ IN HANDLEBARS
« Reply #7 on: August 09, 2015, 11:21:10 AM »
bmw master technician... ha ha ha... now thats funny...

exacerbate the buzz... mine mine mine... all mine...

j o
  • :johnny i parks my 96 eleven hundert rs motobrick in dodge county cheezconsin  :johnny

Offline shoebox1.1

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Re: 5000 RPM HIGHWAY BUZZ IN HANDLEBARS
« Reply #8 on: August 09, 2015, 11:26:33 AM »
I checked the muffler mount was ok just gave the bike a once over and am not seeing anything loose
Let me say this.. I work on cars for a living for 23 yrs my hands might be more tingle prone due to carpel tunnel. My gel gloves might not be good enough.  I think what I'm felling in the bars might be normal. I need to have my dad ride the bike and compare it to the 15 k bikes he's owned.   Thanks so much!
  • mckinney texas
  • 87 k75s

Offline bizzaro

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Re: 5000 RPM HIGHWAY BUZZ IN HANDLEBARS
« Reply #9 on: August 09, 2015, 11:45:26 AM »
Hey, could be worse.  Mine starts to vibrate at 3.8 to  4k+. That sux cause if I ever want to drive 50 to 60, police won't bother you much there, but all the vibs come in about then. Also at 4k I get this annoying buzzing sound in all gears. Reminds me of a remote  controll airplane or truck tires on the pavement?? BBBBUUUZZZZZZZZZZZZZZ! Shoot up to 4.5 or so and it is gone. seems to be a bit louder on deceleration.  ( I am worried it is the splines?) So It is either granny speed or demon speed for me!
  • Vermont
  • Current:1994 BMW K1100LT Previous: 1982 Yamaha virago 920,1973 Honda CB550,1976 Yamaha 650 Special
See Ya in the Twisties,
 Bizz

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