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Discussion Starter · #1 ·
Members have been kind enough to give me advice in the past. Here is my current problem.

I have a 1975 CB500T and just finished installing a new battery, cleaned tank and filters, installed new plugs and cleaned carbs.
The bike started easily for the first time since 1987 based on the registration sticker.
The problem is that I get about 2000 TPMs when the choke is on and without any throttle. When I take the choke off, even without touching the throttle, the RPMs shoot up to 5,000+
Any idea what is causing this? I removed the top of the carb to check that the closed throttle is in the correct position and it closes about 99%.
Help, thanks
 

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Does the slide close 99% or the throttle plate? In order to reach 5000 rpms I'd say the throttle plate isn't closing enough. Either the throttle stop screws or the cable adjusters must be off.
 

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Discussion Starter · #3 ·
The throttle plate closes 99%. I removed the tank and pulled the needle slide so I could see and feel inside the carb. When closed, the left throttle plate has a slight tilt with just barely enough clearance to put the tip of your finger nail under it. I adjusted the right side to match the left plate. It is really strange the way the RPMs just. I am going to have to spend more time trying to figure out what is happening. Thanks Lefty
 

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Discussion Starter · #4 ·
Lefty, I took your advice and loosened the throttle cable adjusters so there is slightly more slack in the cable. It was too tight and the adjustment made a difference. RPMs still too high but much better.
 
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