Author Topic: Whirring Tach  (Read 628 times)

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Offline mono

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  • 1975 Honda CB550, 1978 CB750K (in progress)
Whirring Tach
« on: August 12, 2013, 10:43:28 AM »
recently developed a "whirring" sound from the tach - it's intermittent-ish, but generally becomes audible around 3K RPMs and then increases in pitch until i shift.  i removed and lubed the tach cable and speedo cable, but it still does it from time to time.  i have the cables routed as i always have, with the tightest "bend" at around a 5" radius.

just wondering if maybe it's something inside the tach itself that needs to be lubed -- i was hesitant to spray anything into the gauge itself.

Offline bjbuchanan

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Re: Whirring Tach
« Reply #1 on: August 12, 2013, 03:24:32 PM »
I wouldn't spray in to the tach, you will probably just end up staining the tach face. It could very easily be a bad cable they make noise on their way out. Do you get any bouncing of the tach too? especially when you slack off the throttle
The dirty girl-1976 cb750k, Ebay 836, Tracy bodykit
Round top carbs w/ 38 pilots, middle needle position, airscrew 7/8ths out, 122 main jet
Stock airbox w/ drop in K&N, Hooker 4-1

Don't trust me alone with a claw hammer and some pliers

Offline mono

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Re: Whirring Tach
« Reply #2 on: August 14, 2013, 08:14:29 AM »
the needle stays quite steady, but you're probably right about the cable.  it was on the bike when i got it, and for all i know is the original tach cable.

thanks for the verification to *not* spray lube into the tach, though - i'll just replace the cable and see what happens! :)