Author Topic: CB750 K8 throttle cable loose  (Read 840 times)

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Offline Pavlos25

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CB750 K8 throttle cable loose
« on: June 23, 2015, 02:02:10 AM »
Hi, this is my 1st post on this forum. I am the proud owner of a CB750 K8. Recently my throttle started to play up. When i shift gears, especially from 1st to 2nd and at low rpms, the revs of the engine remain high when shifting. This also happens to a less extend when shifting other gears. When i rev the rpms high from 1st to 2nd this doesn't occur as frequently. I unscrewed the cap that covers the throttle cables on the handlebar and realized that when i first start turning the throttle the cable loosens and after a certain point it tightens. if i release it when loose then the cable doesn't return rapidly. Changed cables but the problem persists. Any recommendations will be appreciated. Thanks.

Wobbly

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Re: CB750 K8 throttle cable loose
« Reply #1 on: June 23, 2015, 05:22:17 AM »
First step is to check installation and adjustments against the manual.

 

Offline evanphi

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Re: CB750 K8 throttle cable loose
« Reply #2 on: June 24, 2015, 07:23:20 AM »
remove cable from carbs. Do the carbs move smoothly and quickly without any cables attached?

Adjust the carb end of the cable(s) first to take up most of the slack. Then use the adjuster at the grip for the pull cable. You can go from "just right" to "too tight" within a 1/4 turn, in my experience. A bit more slack isn't a bad thing.
--Evan

1975 CB750K "Rhonda"
Delkevic Stainless 4-1 Header, Cone Engineering 18" Quiet Core Reverse Cone, K&N Filter in Drilled Airbox
K5 Crankcase/Frame, K4 Head and Cylinders, K1 Carbs (42;120;1 Turn)

She's a mix-matched (former) basket case, but she's mine.

CB750 Shop Manual (all years), searchable text PDF
Calculating the correct input circumference for digital speedometers connected to the original speedometer drive

Offline flybox1

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Re: CB750 K8 throttle cable loose
« Reply #3 on: June 24, 2015, 07:49:07 AM »
Aalso, check the routing.of the cables.   No sharp turns or bends so the cable slides smoothly inside.
Welcome to the forum!!! ;D
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

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Wobbly

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Re: CB750 K8 throttle cable loose
« Reply #4 on: June 24, 2015, 08:17:34 AM »

Offline Pavlos25

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Re: CB750 K8 throttle cable loose
« Reply #5 on: June 24, 2015, 12:27:36 PM »
Thanks for all your useful replies. Will try and find the mistake in a few days.