Will GYT-R or PMB insert change jetting?

4 replies to this topic
  • Redwoods

Posted March 18, 2004 - 07:13 AM


I am going to be getting a GYT-R or Pro Moto Billet exhaust silencer on my 03 wr450 and was wondering if I could jet it now and ride it or should I wait till I put the silencer in as it might change my jetting. I don't want to rejet it if the silencer will cause me to reopen the carb. I do have a zip ty screw so maybe that is all I will need to adjust. Any input would be greatly appreciated. :)

  • Indy_WR450

Posted March 18, 2004 - 08:42 AM


You live in Vail! You need to jet 155 main, JD red needle #3 for summer and 160 main and JD red needle #4 for cooler conditions in early fall or late spring. Insert wont hurt much at that altitude. :)

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • latehit

Posted March 18, 2004 - 10:17 AM


I don't live at the same altitude or have the same bike but I do have the gyt-r insert in my bike with the air box snorkle out and I have stock carb settings. My bike runs very strong however with it getting warmer out it may be running too rich. I think I can compensate with the Fuel screw but if not I will go with a the next leaner main jet. Get familiar and intimate with your carb, your bike will love you for it! :)

  • jwriott

Posted March 18, 2004 - 12:49 PM


I have a PMB and had the GYRT insert and had to rejet to use these. It just ran too rich with the smaller outlet. I dropped the needle one clip and went down one size on the main.

The main reason I finally changed to the FMF Q was that I thought the exhaust seemed extremely hot compared to running the open exhaust.

  • Desracer

Posted March 18, 2004 - 07:34 PM


Just a thought for you. The moto billet unit made the bike run stronger on top compared to the GYT tip. Also my GYT tip mounting bolt hole had to be heli coiled to keep the bolt in. Didnt do anything but twist the air screw here at 3600 ft and it runs fine.


Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.