Another Jetting Question

I have searched and am having trouble finding an answer. I have an 06'wr450 with the free mods done. There is no bog and is strong all the way thru. Question is with stock jetting am I taking a chance of burning a valve. I have put on the TT AIS but still have a lean pop when letting off the throttle. I like the way it runs now just worried when a friend told me I might burn a valve if I don't rejet. Also thanks for a sight that has so much info its great!

It is suppose to pop a few times on decel. Also don't try reading a plug as thats inconclusive also. These carbs are a PITA to get just right but odds are your not to lean. I'm using a very open slip on muffler and have openned the air box up on my 06 and it is fine tuned with a JD red#5 and 168 main jet when less than 50 degrees. I'll lean it out more as it warms up to JD red #4 and 165 (stock) main.

If you've done all the free mods I'm assuming you've opened up the air box and removed your baffle from your exhaust. The stock jetting is ridiculously lean, take the plunge and re-jet your bike, you'll be amazed at the difference.

Yep the air box is opened and baffle out of the exhaust

temp and altitude plays a big factor in performance. I run from sea level to 3000' On the Dyno, mine was running lean after I did all the mods and installed the AIS kit. I had to turn my air screw out 2 3/4 to get it right on.

Check the plug, I can see the difference in mine when I change jets. Just start with a fresh one each time you re-jet. Stock jeting is lean and your plug may be white. As you richen things up the plug will get brown and the bike will run better.

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