To be honest if it's already plugged in and showing 3000, or randomly moving about, then it sounds like you need a new one anyway.
3000 is the fault code, which will show up if the TPS is faulty, or unplugged.
The position it's meant to be on is 5000, after you've unplugged it then plugged it back in, and if it's working okay but is a bit offset and needing adjustment then it would be either sitting on 0rpm or 10,000rpm.
To remove the TPS outer plug there is a small catch that needs to be released, i personally use my ignition key to GENTLY unhook the catch just inside of the front of the plug. Don't start heavily twisting screwdrivers, or your key, as you will break something.
Look in the photo of the TPS below, and see the little tab in the middle at the top, (on the bike it will be rotated 90 degrees to the left), the outer casing just needs a bit of encouragement to unclip it.
When unplugged turn the ignition key to the on position (don't start engine) and you'll see the RPM needle will go up and down from 0rpm to 3000rpm.
Then plug it back in and see where the needle then settles.
0rpm or 10,000rpm would normally just mean adjusting back to 5000rpm.
To adjust it you need a T25 tamper proof torx allen key, (with the hole in the middle).
Just undo the 2 screws, rotate the TPS until it lands on 5000rpm, then tighten them back up, and that would normally be it.
The fact you're getting a 3000 reading without even touching it does not really sound too hopeful though so be warned you most likely have a knackered one.
Personally i can feel the bike is very wrong when a TPS is on it's way out. If you're new to biking though (?) then you could be excused for not realizing an issue, until you ride it once it's fixed or replaced, then you'll know how wrong it was.
The bike will feel a bit jerky and erratic when riding, needing a bit more clutch control, especially below 3000 revs. There will be no real smoothness in running at all.
Unless it blatantly goes to 3000rpm after trying to adjust it then put it in the correct position then test it again in a couple of days and see if it has stayed on the 5000rpm mark.
If it refuses to budge at all, like one of mine did, stuck on 10,000, then that also is a sign of buying a new one.
If it needs replacing, don't buy a used one, as it will only break down very soon again, and is false economy. A used TPS will be a minimum 14 years old, with unknown mileage on it so don't even consider it.
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