Zyp T Fuel Screw

What does this do for the bike? I see a lot of people have these. I have an O6 WR450F and have done the grey wire mod, removed the snorkel, removed the AIS crap, and have the JD Jetting kit sitting in the house waiting to be installed. I also have the YZ throttle stop. What will the Zyp T screw add?

...What will the Zyp T screw add?

Adjustability to fine tune your jetting. For example, if your throttle response feels crisp, but you're getting a little popping on decel, a half turn out on the fuel screw will likely eliminate it. The fuel screw is the 4-Stroke version of the 2-stroke air screw. Read the articles on it in Thumper FAQ...SC

It basically allows you an easy way to adjust the fuel mixture. Of course it is not a substitute for correct jetting but it can get you that final tweak after everything else is set up right. If you don't have the fuel screw you need to rotate the carb out to adjust the fuel mixture. I don't mess with mine as much as I should. Hopefully someone else can give you a better answer. It is a cheap and easy mod that gives you some easy tuning options so I would recommend it. I've heard of some people snapping the screw in half because they try to turn it too hard when they are closing it all the way so be careful.

I looked for the Thumper FAQ but can't seem to find it. Can you put a link to it? I did a search on Zyp T and didn't get much.

There are three articles from MXA at the bottom of the Thumper FAQ jetting page. Scroll down, click, learn :applause: ...SC

It makes it really easy to adjust the idle mixture. It's almost impossible with the stock screw. Try the one that pro moto billett sells. It's machined from brass rather than aluminum like most of the others so it's a lttle tougher.

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