jonnyrocket56 Posted October 23, 2005 is it okay if your bike backfires every now and then or is it okay for my 2002 YZ426F to backfire on every deceleration? also i would like to know what jets you guys us in your bike? Share this post Link to post Share on other sites
hey d00d Posted October 23, 2005 it could also be a leaking valve because my dad had a wr 426 that backfired every deceleration and it was a leaking valve, not exactly a good phone call when that came in Share this post Link to post Share on other sites
97chevy Posted October 23, 2005 Is it backfiring or is it popping? I thought it was if it was popping your pilot is too lean and if it is backfiring your pilot jet is too rich. Thats how I understood it but not 100 %. Have you tried adjusting your fuel screw on the bottom of the carb? Share this post Link to post Share on other sites
grayracer513 My Ride Posted October 23, 2005 The two major causes, once again, are a leak in the exhaust system, either at the midpipe/header joint, or at the head, and lean idle mixture. Mild decel popping, or exhaust backfire is normal and harmless. Share this post Link to post Share on other sites
