1. Husqvarna Motorcycles Made In Sweden - About 1988 and older

Non start - 1979 125cr - help please

Discussion in 'Vintage/Left Kickers' started by Ruairi, Jul 7, 2019.

  1. Ruairi Husqvarna
    AA Class

    Location:
    Gloucester United Kingdom
    Husqvarna Motorcycle:
    125 cr 1979
    The engine has been rebuilt. Compression is good.
    Good spark at plug. Fuel present in float bowl.
    Fuel poured into spark plug hole enables engine to start briefly and there is a “phut” through the carb as it dies.
    I have kicked it over and over and it’s not even trying to fire.
    I am presuming the timing is out? Unfortunately the link for the ML/MK Engine Manual available on this site is corrupted so I am a bit stuck at the moment because I have not got a clue re Motoplat ignition.

    Any advice or tips very much appreciated.

    May need a set of experienced eyes on it so any advice re good workshop in England would be most welcome,,

    Thank you
  2. markt2 Husqvarna
    A Class

    Location:
    Nevada
    Husqvarna Motorcycle:
    1976 250CR (times 2)
    Other Motorcycles:
    Several vintage Yamahas
    I'd start by carefully cleaning the carb including removing the jets, and yes, again, if it's already been done.

    Sounds like maybe a blocked pilot jet (and/or starter jet if Mikuni)
  3. Ruairi Husqvarna
    AA Class

    Location:
    Gloucester United Kingdom
    Husqvarna Motorcycle:
    125 cr 1979
    Hi Markt2
    Its a bing 84 but yes will strip it down and go through it.
    This episode may encourage me to go Mikuni !!
    Thank you
  4. stormer254 Husqvarna
    AA Class

    Location:
    England
    Husqvarna Motorcycle:
    More than I dare let her know
    Other Motorcycles:
    Yes!
    What condition are the reeds in?
  5. visiteur1948 Husqvarna
    Pro Class

    Location:
    france Europe
    Husqvarna Motorcycle:
    husqvarna only
    have fuel in the spark -plug ?
  6. Vinskord Husqvarna
    AA Class

    Husqvarna Motorcycle:
    400 CR
    Pages from Workshop Manual for Motoplat:

    MP 1 - Copy.png

    MP 2 - Copy.png

    MP 3 - Copy.png

    MP 4 - Copy.jpg
  7. Ruairi Husqvarna
    AA Class

    Location:
    Gloucester United Kingdom
    Husqvarna Motorcycle:
    125 cr 1979
    Thank you guys all very much appreciated. Shed time booked for later in the week so i will let you know how i get on.
  8. justintendo klotz super techniplate junkie

    Location:
    mercer, pa/northwest pa
    Husqvarna Motorcycle:
    84 250,86 400,87 430,88 250,95 360
    Other Motorcycles:
    99 kawasaki zrx 1100
    i would bin the bing even after you get it running..just too easy dealing with the mikuni vm..easy to get parts and tune
    DeathFromAbove likes this.
  9. Picklito Husqvarna
    Pro Class

    Location:
    Northern Kalifornia
    Husqvarna Motorcycle:
    430, 430, 430...
    Other Motorcycles:
    KTM 150xcw
    Longshot, but check that the reeds have not glued themselves shut. If this is a resurrection of a long-unused bike, I have seen this! Reeds varnished so badly that they won't open. You can have good motor, good compression, good spark, good timing, good carb, but it just won't fire. Fooled me well, that one.
    hvaloz2 and markt2 like this.
  10. Ruairi Husqvarna
    AA Class

    Location:
    Gloucester United Kingdom
    Husqvarna Motorcycle:
    125 cr 1979
    Carb has been re-stripped, blown through with air gun and I am convinced no blockages. Bike will not start. So i have removed the reed valve block. Nothing looks to be gummed up. All the bits open if i prod them. That said reed valves are new to me so i am unsure how flexible they should be. Mine open and snap shut. Not sure how old these things are. £56 to replace when i possibly dont need to.Damn frustrating.
  11. Picklito Husqvarna
    Pro Class

    Location:
    Northern Kalifornia
    Husqvarna Motorcycle:
    430, 430, 430...
    Other Motorcycles:
    KTM 150xcw
    Ok next step: Did you verify ignition timing as above?
  12. Ruairi Husqvarna
    AA Class

    Location:
    Gloucester United Kingdom
    Husqvarna Motorcycle:
    125 cr 1979
    Not yet re timing. That is next job on Sunday night when i am next off work. Thank you
  13. visiteur1948 Husqvarna
    Pro Class

    Location:
    france Europe
    Husqvarna Motorcycle:
    husqvarna only
    3435_1925_r-glage-niv-cuv.jpg

    important =test your BING 84 this !
    parralele=parallel
    flotteurs libres = free floatting
    reglage=setting
  14. Ruairi Husqvarna
    AA Class

    Location:
    Gloucester United Kingdom
    Husqvarna Motorcycle:
    125 cr 1979
    Thankyou Vinskord for putting up the ignition timing pages. Thank you Visiteur1948 i will look to see how my Bing is set up. Justintendi yes i will be replacing with Mikuni at first opportunity. What size Mikuni and jetting are any of you guys using onyour125 Husky please?
    Its shed time later so i am hoping today us the day it fires up!!!
  15. visiteur1948 Husqvarna
    Pro Class

    Location:
    france Europe
    Husqvarna Motorcycle:
    husqvarna only
    for me BING 84 is perfect with new parts main jet and needle jet 2.80 !
    but is possible ! CARB MIKUNI 125 YZ or 125 CR HONDA KEIHIN !
    keihin 35 sur 125 ebay.jpg
    KEIHIN 35mm
  16. dmcoz Husqvarna
    AA Class

    Husqvarna Motorcycle:
    1974 CR250, 125 2003 TE250
    I would check for a massive airleak...as that will cause it not to start even if everything else is correct...ask me how I know !!
  17. ruwfo Administrator

    Location:
    NJ
    Husqvarna Motorcycle:
    1980 390CR,1982 430CR, 1987 250WR
    Ok, How long did it run for, when you got it running, 10-15 seconds, or enough to rev it up?

    If it ran for a bit & then died , then ignition & timing don't sound like your problem.

    Sounds like carb, or air filter clogged, i had left a rag over the air box on the 2 stroke street bike once..duh


    Start from the beginning again before you try starting again.. some of these may sound dumb... double check
    them any way..

    1) verify you've got a nice blue spark, re-check coil wire & connections , spark plug cap, did you re paint the frame or have it
    powered coating, if so check the ground to frame (coil mount).

    2) Pull the pipe off, see if there fuel in the cylinder, check to make sure the piston not in there backwards.

    3) Put in a brand new plug, even if there's a new one in there

    4) Check your kick switch/button, disconnect for now..

    5) Check you carb slide, does it open & close completely & not hang up, when you open & close the throttle?

    6) Petcock/ fuel tap, does it work correctly on & off, flow good?

    do those simple things first, then let us know..


    Husky John
    DeathFromAbove likes this.
  18. DeathFromAbove My Cat Says AREAR!

    Location:
    North New Jersey
    Husqvarna Motorcycle:
    72 450cr 73 360rt 77 360auto 83 500x
    Other Motorcycles:
    2x 75 DT400 80 KDX175 ZRX1100
    Make sure the slide bottoms out in the carb with the idle adjust screw out.
  19. dmcoz Husqvarna
    AA Class

    Husqvarna Motorcycle:
    1974 CR250, 125 2003 TE250
    I say again, do a leak down test before doing anything else . Air will not only leak past crank seals but also reed gaskets, exhaust flange gasket, base gasket and past the head. If it is a big airleak it will not start.
    DeathFromAbove likes this.
  20. DeathFromAbove My Cat Says AREAR!

    Location:
    North New Jersey
    Husqvarna Motorcycle:
    72 450cr 73 360rt 77 360auto 83 500x
    Other Motorcycles:
    2x 75 DT400 80 KDX175 ZRX1100
    I had a problem just like this on the 360 auto! After torquing all was well.