I have a stock 2000 YZ125. I have the clip in the third position, 350 main jet and standard needle. Air screw 1.5 turns. During the last week, I have been riding at sea level with a temperature of 70-75 degrees and the bike has been running very good. I have been using a premix of 32:1.
The only problem that I have been having is when I start the bike up for the first ride of the day, the bike will start up (without choke) on the first kick and then I can not get the bike to rev up. It will idle, but will not take any throttle without bogging down. I have tried to let it warm up on idle while giving it short blips of throttle to clear the plug, but after a 30 to 45 seconds, the plug fouls out and that is it. Switch to a new plug and go riding the rest of the day without any problems at all.
This has happened to me three times during the last week of riding. I have been using a NGK BR9EG plug.
Any suggestions on how to fix this would be much appreciated.
Thanks,
Jeff
The only problem that I have been having is when I start the bike up for the first ride of the day, the bike will start up (without choke) on the first kick and then I can not get the bike to rev up. It will idle, but will not take any throttle without bogging down. I have tried to let it warm up on idle while giving it short blips of throttle to clear the plug, but after a 30 to 45 seconds, the plug fouls out and that is it. Switch to a new plug and go riding the rest of the day without any problems at all.
This has happened to me three times during the last week of riding. I have been using a NGK BR9EG plug.
Any suggestions on how to fix this would be much appreciated.
Thanks,
Jeff