Help- No Compression

2 replies to this topic
  • Vinnie

Posted January 26, 2002 - 03:59 PM


Has anyone had this problem? Feels like my decompression lever is stuck on! The bike is a 99 400 and just washed it after a weekend of riding and now it won't start. It has a little compression and I can kick it thru with little problem. When I squeeze the compression lever it feels like it always does (no compression felt). The lever and cable appear normal with no hangups and lever travel feels normal! any info would be great before a trip to the dealer.

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  • Boit

Posted January 26, 2002 - 04:10 PM


I ran into this exact same problem several months ago. For some mysterious reason, my engine had about half the normal compression when I went to start it. I kicked it through about 20 times or so and it suddenly started. I let it run for about 2 minutes and then shut it down to check the compression. It was back to normal. You might just try and kick it through several times to see if the compression returns. I also experienced this on my '94 KLX. Perhaps one or more of the valves gets a deposit around the seat that prevents a good seal and by kicking it through, it gets dislodged. I dunno.

  • sirthumpalot

Posted January 27, 2002 - 03:19 AM


Had the same thing once on my '01. I made the mistake of sqirting some carb cleaner through the carb jets while it was still in the bike. Then when I went to start it there was almost no compression at all. I kicked it 3 or 4 times and it finally started. I let it run for about 5 or 10 seconds and then shut it off and the compression was back to normal. I have no idea what caused it but I've had no problem since.

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