Starting Problems

3 replies to this topic
  • reed_YZ426

Posted October 26, 2001 - 07:28 PM


My bike hasnt been starting in 2-3 kicks like it has been lately. could this be due to the cold weather around here now? or is there maybe some other problem its taking like 10 or more kicks to get it going.

  • Boit

Posted October 27, 2001 - 05:45 PM


Cool weather certainly COULD be the culprit. Cold air is denser causing a leaning condition. Try enrichening your fuel screw a little and see if that helps. If your spark plug is a little old, you might try installing a new one.

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  • zack_attack190

Posted October 29, 2001 - 04:12 AM


<BLOCKQUOTE><font size="1" face="Verdana, Helvetica, sans-serif">quote:<HR>Originally posted by reed YZ426:
My bike hasnt been starting in 2-3 kicks like it has been lately. could this be due to the cold weather around here now? or is there maybe some other problem its taking like 10 or more kicks to get it going.[/QUOTE]

My bike started just fine last week it was hot, this past saturday I could not start it at all. I have had this problem before.

I will install a new plug and richen the mixture, could this be related to a stuck
compression release or timming prolem?


  • Boit

Posted October 29, 2001 - 08:42 PM


Troubleshooting the compression release mechanism is very simple. First, make sure you have a little free-play at the lever on the handlebars. Check this free-play by turning the bars full stop in both directions and make sure the lever never loses it's free-play. What you are looking for here is that the cable gets in a bind and pulls the release open on the lifter bucket. The release rod that goes into the head above the right exhaust valve bucket is shaped like a "D" where it fits on top of the bucket. The flat part of the "D" rests on the bucket and when you pull in the lever, the shaft turns and the oval part of the "D" presses down on the bucket. . . much like a cam lobe. All you need to do to verify that this shaft is working correctly is to pull in the release lever and watch that the shaft turns ~90 degrees and then returns when the lever is fully released. The lever should be fairly hard to pull in because it takes some serious pressure to compression an exhaust spring. The whole thing is a very simple and straightforward mechanism. Something else to consider is that once a valve, or valves get too tight , the valve(s) can't quite fully close and compression is compromised. As the engine gets up to operating temperature, the valve lash gets even tighter and the valve(s) hold open a little bit more than when cold. (Metal expands when heated). My'00 has at least 120 hours of operation on it and it still starts 1st or 2nd kick in any kind of weather. I have been using C-12 exclusively since it had about 3 hours running time and that may add to it's good starting. I run a #162 main jet in weather below 40 degrees, a #160 between 40 and 60 degrees, and a #158 above 60. I've never needed to change the pilot jet or clip position, just make small adjustments to the fuel screw. The FCR carbuetor is pretty sensitive to dirt and needs a regular thorough cleaning. . . especially the accelerator pump ciruit. If you aren't willing to do a lot of maintenance on this bike, you will probably experience a lot of little nagging problems that can escalate into large problems quickly if ignored. As a last thought, check the bottom of the carb vent tubes and make sure they aren't plugged with dried mud. Most guys now either cut the ends off at an angle, or split them about a half inch up the end. Also make sure the vent tubes are not kinked or in a bind that can prevent proper ventilation of the carb. Hope this helps and sorry about the rambling. I get stuck in details at times.

The ignition timing is set from the factory and should not need adjusting. However, the manual describes how to check it. The throttle position sensor has an affect on timing so if you change the initial timing, it changes the dynamics of the MAP. So, tread carefully here.

[ October 29, 2001: Message edited by: Boit ]

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