K1 RM125 sounds bad.No idea why.

martadavid

Member
May 13, 2018
2
1
It sounds like running rich, but the spark plug is nice brown, and i have just replaced my crank seals. My ignition is retarded a bit. Running on 95octane, not better with 100 octane. Premixing with motul710 1:40. The bike pulls great, but sounds bad for me. The bike was rebuilt and I ran 10hours since rebuild. Stock nicasil cylinder, Vertex piston (C size),new bearings(Prox(ntn)),and seals. Please help me why it doesnt sound well! Heres a video where i pushing it, but its not clear sound.

i cleaned the carb several times. it was running with 460 main jet, the spark was black.I replaced with 430 and its nice brown, and the sound of the bike is better, but still not clear.I dont want to go smaller main jet because it would be too lean, i dont want to seize it. pilot 25(stock 40), Main 430(stock 460), needle in the middle, air screw 0.5 out(if 1,5 out it bogs when i pull the throttle at low rpm.)Spark brown.(at full throttle i cut out the engine and i screw out and check the spark plug.)
Reed seemed OK.(no gap)
Videos:

 

Attachments

  • spark1.jpg
    111.7 KB · Views: 552
  • spark2.jpg
    97.4 KB · Views: 539

The Redrider

Member
Jun 14, 2019
238
32
Sounds good, I heard a little blubber on video 2, but noting I would be concerned with. Plug looks i-ight, im not sure about 1-40 mixture of the oil. Do you mean 40-1?
 
Cookies are required to use this site. You must accept them to continue using the site. Learn more…