Maybe I'm just stoopid

I just had the carb off my '01 yz426 to do the fuel pump mod and lengthen the pilot screw.Upon reassembly,it acts like it's bouncing off the rev limiter all the time.I've already done the blue wire mod so I have a hard time believing thats the problem.It only does it after about 4k rpm or so and choke or hot start input does not affect it,it runs great off the bottom.Any ideas from you folks??

A common mistake is to put the spring plate back in upside down. It looks as if it should be installed with the round edge down, but the flat edge on the side with the hole in it is the one that belongs on the bottom. #11 in the picture:


I only had the bowl off it.Reset the float level and pulled the pilot out for modification to make it longer.pulled it back off today and blew out all the jets and still same problem.Reminds me of cars at work bouncing off rev limiter.{I'm an auto mechanic}Thanks for your input.

What are you talking about when you say you lengthened the pilot screw?

I extended the length so I can adjust it easily.

And the spring, washer, and O-ring all went back in, right?

It's all there.I thought if i richened it with the choke or leaned it with the hot start it would change,it doesn't make any difference.It almost sounds "pingy" like a two-stroke when it quits.{kinda goes bing bing when it quits revving}

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