Hey guys,
when I got this bike it would idle really high and shut off when choke disengaged. Cleaned carb & 2nd kick had it running. Was idling low so I turned throttle screw clockwise and you'll see what happens next in the videos below.
Bike: 1998 yz125, big bore kit 144cc?
Known problems to date (not sure of relevance to issue):
1) 2 nuts and bolts missing in the intake boot, (not sure if air leak could cause high idle)
2) Hose clamp for intake boot missing
3) Main jet is a 330, Revzilla calls for 340-350 (part coming today)
4) Pilot jet looks possibly bent.. have a new 47.5 coming today. (Revzilla calls for 45-50)
5) Tension spring + both o-rings missing from exhaust pipe
6) Throttle spring in carb is bent (can feel when opening up throttle on grip)
7) Air vent hoses on carb missing + fuel vent hose.. but just cleaned carb.
Videos of issue:
https://streamable.com/2f0ve
https://streamable.com/7fa5a
Note that at 00:09 of the second video, I hit the kill-switch and let go to take one more crack at the throttle screw. That's the reason for bogging down.
Other relevant concern:
I wasn't sure how much to tighten the throttle cable at the top of the carb.. I noticed that tightening it dropped the slide and loosening it, raised it. Where is the slide supposed to be at rest position?
(i.e: Halfway, all the way down, etc).
Any and all help is greatly appreciated!
I'm just starting to dive into the world of internal combustion engines!