400F throttle stop screw

Just bought a '00 WR400 and the previous owner says he removed the throttle stop screw. Is this okay? I know some have said to cut it down to shorter length and others have said to replace it with a '01 yz426 screw for about $8. What's the word?

It was completely removed by the previous owner of my used '98 WR400. Never had a problem.

If you run it without one at all the slide will smack the inside of the lid everytime you hit full throttle. Eventually you will damage the top of the slide or the inside cover. While replacing the cover is not going to send you to the poor house, the slide isn't cheap to replace.

The best way to replace it is to go to remove the carb and go to your local hardware store. Purchase a small metric bolt and also two small nuts as locks. Thread the bolt in the housing from the bottom to the top and put the other nut on. Open the throttle until the slide just reaches the top of the throttle body. Adjust the bolt to allow no more travel than that. Add Locktight and Tighten the lock nut and reinstall the carb.

Cost me about 60 cents to replace the on on my YZ.

Good Luck...

Bonzai :)

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