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Awful screeching sound at 5500 rpm 5th gear???

leviathan707

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So... first post here. Bike: 1980 cb750f dohc. Have a 4 to 1 kerker megaphone exhaust. pod filters with the jet resized to 110? i forget had it go 1 size up from stock. But onto the problem. Bike runs rough(pod filters i know) but power is there when Im on a straight and I give it some gas to get up there when I'm in 5th gear and hit 5500 rpm this horrible screeching sound happens i always back off the throttle never try to go past it. never tried hitting 5500 in any other gear either. but as soon as I let off its gone. Ill be happy to answer any questions that may help with ideas on what it might be.
 
You apparently relate the screech to RPM rather than speed, so is it safe to assume that the sound is coming from the engine?

I'd certainly try passing 5500 RPM in a lower gear. Seems to me that 5500 in 5th will give you the highest speed when the screeching starts, and that might point to wheel bearings, brakes, or heck, even the speedometer cable.

From where I sit, more information is needed.
 
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