Author Topic: What is this screw for on the throttle linkage  (Read 372 times)

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Offline JDrider

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What is this screw for on the throttle linkage
« on: August 17, 2023, 04:47:19 PM »
1975 cb550k1
Can’t figure out what this screw and spring is for on my carbs
JD
1975 CB550K1

Offline Gurp

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Re: What is this screw for on the throttle linkage
« Reply #1 on: August 17, 2023, 10:15:18 PM »
Idle speed adjustment

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Offline bryanj

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Re: What is this screw for on the throttle linkage
« Reply #2 on: August 17, 2023, 11:45:27 PM »
Idle speed is the big one on the end
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Offline dave500

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Re: What is this screw for on the throttle linkage
« Reply #3 on: August 17, 2023, 11:51:37 PM »
that screw sets the max opening,the idle speed is easy to adjust underneath with this thumb screw.

Offline Little_Phil

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Re: What is this screw for on the throttle linkage
« Reply #4 on: August 18, 2023, 01:57:26 AM »
Only seen that extra spring on the throttle shaft on Pd carbs. Is it helping with opening or closing?

Offline dave500

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Re: What is this screw for on the throttle linkage
« Reply #5 on: August 18, 2023, 02:17:27 AM »
neither,it keeps tension on the screw to hold it where its set,the screw sets the max throttle opening.

Offline Little_Phil

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Re: What is this screw for on the throttle linkage
« Reply #6 on: August 18, 2023, 04:44:13 AM »
Yes just looked it's normal. But is the screw just the maximum open stop screw.
« Last Edit: August 18, 2023, 04:46:53 AM by Little_Phil »

Offline JDrider

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Re: What is this screw for on the throttle linkage
« Reply #7 on: August 18, 2023, 05:00:40 AM »
the screw isnt attached to anything to adjust. Its just a screw with a spring. Or am I missing something?
JD
1975 CB550K1

Online denward17

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Re: What is this screw for on the throttle linkage
« Reply #8 on: August 18, 2023, 05:07:11 AM »
Does it have anything to do with the choke and fast idle?

Do you have a cable pull for the choke on this model?

Offline JDrider

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Re: What is this screw for on the throttle linkage
« Reply #9 on: August 18, 2023, 05:36:39 AM »
no cable pull for choke on this model.
JD
1975 CB550K1

Offline JDrider

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Re: What is this screw for on the throttle linkage
« Reply #10 on: August 18, 2023, 05:47:12 AM »
So looking at other videos, it is to keep the throttle pull limited.
the screw sets the max throttle opening like Dave 500 said.
JD
1975 CB550K1

Offline dave500

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Re: What is this screw for on the throttle linkage
« Reply #11 on: August 18, 2023, 01:55:08 PM »
watch what it does as you crank the throttle open.