1989 Suzuki rm125

Discussion in '2 smokers' started by emti, Aug 14, 2020.

  1. emti

    emti Been here awhile

    Joined:
    Aug 26, 2010
    Oddometer:
    389
    Location:
    northern n.y.
    Im working on a 1989 Suzuki rm125, after removing the exhaust valves (AETC power valve) I found a small hole in each "port" in the cylinder head casting where the valves slide back and forth. . They don't appear to be a machined hole but are in approximately the same spot in each port, and I think they go into the water jacket? I can't find any reference to this in the manual or on line. I believe its damage or a defect, as this bike was rode hard and neglected. Has anyone else seen this in a two stroke power valve? Is it for lubrication? Thanks emti
    #1
  2. emti

    emti Been here awhile

    Joined:
    Aug 26, 2010
    Oddometer:
    389
    Location:
    northern n.y.
    The holes were possibly caused by corrosion inside the water jacket and/or cavitation of the coolant,.. maybe. Anyway the cylinder is unusable/unrepairable as there is no cost effective repair. Thanks emti
    #2
  3. offroadtoys

    offroadtoys Been here awhile Supporter

    Joined:
    Feb 14, 2013
    Oddometer:
    355
    Location:
    Oak Harbor, OH
    That's a bummer but I see that era RM on FB marketplace and craigslist pretty regularly. Should be able to find a used serviceable one, I would think. Good luck. I always liked that year RM's and have this brochure somewhere at home:

    Suzuki RM 1989 Lineup.jpg
    #3
  4. Foot dragger

    Foot dragger singletracker

    Joined:
    Dec 27, 2006
    Oddometer:
    25,963
    Location:
    chico,just below rag dump(nor-cal)
    Good epoxy can be an amazing thing.
    It has been used to fill in ports when a port job has been over done. Clean it and sand it if possible and epoxy the holes shut if your sure they go into the water jacket cavity.
    #4
  5. emti

    emti Been here awhile

    Joined:
    Aug 26, 2010
    Oddometer:
    389
    Location:
    northern n.y.
    Thank you, Ill look into that .
    #5
    Foot dragger likes this.