Hot Starting Problems 03 450f

3 replies to this topic
  • GreggT

Posted September 14, 2004 - 11:05 AM


I race desert. This weekend I got into a slippery section and backed off the throttle enough to hook up the rear tire again and when I got back on the throttle it went poof. I couldn't get it started, I tried hot start with no throttle I tried hot start with full throttle, and both without hot start. It finally started but cost me the race. Is this a jetting issue or just something I have to live with. I realize the real problem is the accellerator pump, but what now?

  • Indy_WR450

Posted September 14, 2004 - 01:27 PM


Try this web site there is real good information on tuning the AC pump:

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  • SureBlue

Posted September 14, 2004 - 04:38 PM


No, you do not have to live with it! 1:Ensure your jetting is correct. 2:Adjust the fuel screw for each ride. 3:Never touch the throttle cause it has not stalled due to lack of gas. 3:Calm down, always use the hot start and set a bit higher idle. 4:Give a good solid kick. If the bike has not started after five solid kicks, close the petcock, tip the bike to drain the carb, open the throttle slowly and KEEP it open and kick several times to vent the cylinder. 5: Close the throttle, open the petcock and tip the bike again to fill the carb. Do not touch the throttle and with hotstart on, the bike fires up by 3rd solid kick. Turn back down the idle and hotstart and go. If this does not work you have something wrong with your carb or the sparkplug has retired. And yes, an iridium plug is definitely of help, as well a bit higher idle. I have learned the hard way and since, no starting problems. My old 426 was a staller and blew plugs, but the 450 has given no headache. Maybe you guys have other rituals, let's hear them! :thumbsup:

  • SureBlue

Posted September 14, 2004 - 04:52 PM


BTW - I stress the importancy of setting the idle some 1/4 turn higher when starting hot; the bike may WANT to fire up but it simply WON'T. :thumbsup:

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