I purchased a Uni air filter and plan to remove the airbox lid. Which size jet should I change to. I have stock exhaust, no engine mods, and live in Virginia at a low elevation, less than 1000 feet. Any input is greatly appreciated.

 

I experimented with my Z alot when I first got it. I found no benefit in removing the airbox lid with the stock exhaust. The stock silencer is very restrictive. It does no good to let more air in if you can't push it out. I would suggest removing the snorkle cover and using a 135-140 main jet. Here's my setup, and it runs great. 1. Removed peashooter from stock silencer. 2. Uni filter. 3. Removed snorkle cover. 4. 140 main. 5. Moved washer from above needle clip to below.

I tried removing the airbox lid and bigger jetting, but none of it worked as well as the above setup. I finally ordered an aftermarket exhaust this week and I'll be running no lid with the new setup. Good luck.