too rich


3 replies to this topic
  • jwcrf05

Posted June 25, 2006 - 07:17 PM

#1

my bike was jetted so good all spring long but the last two times i went for a ride the bike had a lot of sputtering and some hesitation. Last week I fouled a plug trying to start it. I know I can probably fix this with jetting but my main concern is can something else like valves or something more serious cause an overly rich problem.

  • jbrooks26

Posted June 25, 2006 - 08:17 PM

#2

Weather changes can cause lean or rich conditions. I am not sure if it would effect it enough to foul plugs or not unless it was extreme. However, if you have never checked valve clearances then now would be a good time to do so. It doesn't take long, and if that is what you really need then it will save you time chasing down jetting to mask the real problem. Just my 2c, hope this helps.

Josh

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  • grayracer513

Posted June 26, 2006 - 08:19 AM

#3

You probably had it too rich all this time, but with the warmer whether, it got to be way too rich. 4-strokes are pretty tolerant of mixtures that aren't quite perfect, especially if they're rich. Even that has a limit, though.

A lot of the guys who bought '06's and found them lean are going through this now after having bumped the jetting to a 170 main and a 48 pilot. They're having to back away from that a bit in many cases. My '06 seems happy with a 165 and a 45.

  • mxrayser

Posted June 26, 2006 - 08:47 PM

#4

my bike was jetted so good all spring long but the last two times i went for a ride the bike had a lot of sputtering and some hesitation. Last week I fouled a plug trying to start it. I know I can probably fix this with jetting but my main concern is can something else like valves or something more serious cause an overly rich problem.

Went from 48 pilot to 45 and 170 main, did good up and down the block, but this weekend will tell the tale, ridin witha buddy and KTM is on the menu





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