2003 KX 125 flywheel weight?

Just picked up an '03 KX 125 for the wifee. Shock and linkage bearings are gone but for $1100 I think I did ok. I noticed while riding it that when the revs drop a little bit, and you roll on the throttle, the thing bogs. I realize that 125s don't do well in the low low RPM range but this isn't right. Wondering if anyone had good jetting specs for this bike? (I live in the N. Texas area) My initial thoughts are that the pilot is too rich.

Also, I was interested if anyone looking at this forum has ever tried running a flywheel weight on a 125. I realize this might sapp what little power the 125 has but I was thinking it might make the bike more trailworthy for my wife. We ride mostly cross country style courses together; although she has been known to venture onto the mx course from time to time. I know the new KTM 150XC has a heavier flywheel. Any thoughts.

i cant see jeting being the issue unless someone has been screwing around in the carb before u got it.....but you can look up a jetting chart for the bike and check the jet sizes for yourself. Also have a look at the needle hight, try to lean it out a bit. let us know how it goes

You might check the compression also, if its below like 120ish you may want to think about a new topend rebuild... Or it could be a leaky crank seal sucking up some oil and building up causing a bog.

The best way to really start would be some plug chops up and down a 1/4-1/2 mile road and see which sections of the throttle opening are too rich. Then its just a matter of small incremental changes to your jetting till you get it right:thumbsup:

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