7.5"

 

In my opinion, a 1/4 windshield would be next to worthless, unless you're a REALLY short guy. You need one that's at least tall enough to keep the direct blast of wind out of your face. Plus, with a 1/4 windshield, you'll be constantly eating dust, sand, gravel, and debris, if you're following anybody. A 1/2 windshield (lower half) does the job quite nicely. With a 1/4 windshield, you might just a well not even have a windshield. My two-bits........

Cheers

 

Have a half, it's too tall. Once dust gets on it or mud I can't see. I already cut it down.