New needle jet or what?

Discussion in '2-Stroke Engines' started by Biker, Jul 27, 2010.

  1. Biker

    Biker New Member

    Since i last posted with the running rich post (4stroking,48cc NT carb) i soldered up the main jet and re-drilled smaller,(couldn't source main jets easily here)now it's running terrific over 1/2 throttle and good on most acceleration,but seems obviously still to rich at low speed.Pity they don't come with a low mixture adjustment eh!Anybody have any idea's how to smooth it out down low?Needle is at highest clip position,Float set at 21mm.Plug is a new bosch equivalent to the b6hs.Are there different needles or needle jets available now?
    Has anybody filed the slide cutaway and found that helped.
    Apart from this the engine is running well,round trip to work near on 30km all flat roads.

  2. motorpsycho

    motorpsycho Active Member

    heck, after all that work, i would just let it run won't hurt anything...unless it runs terrible and wants to quit running on you.
  3. Biker

    Biker New Member

    Success finally,ye-ha.
    Yeah i know were your coming from motorphsho,but somethings just bug me and won't go i tried something else,with the view that i could reverse it if it didn't work,and work it has,for me i'm now 100% happy.
    Leaning out the lower range was a bit of a problem as the clip was already in the top notch.So i took a 11/32" drill bit and drilled into the slide,using the needle hole as the center.I wanted to simply be able to lower the needle even further.I went in perhaps 1/16",anyway it was enough to drop the needle say another notch or 2.
    I then placed a dab of clear silicon on top of the needle and allowed that to dry,so that the washer would hold it down on it's seat.That was last night and this morning i took her out for a run.Wow,i knew i'd scored as soon as she started,she ran nice and smooth even cold,even better was after releasing the clutch she took of with no shaking because of the popping previously. And idle has been turned way down because it feels more reliable to have it there.
    Motor now revs cleanly right off idle.
    So why did i need to take such drastic measures,i have no idea.But if the stock needle had 2 more notches above the 5 already there i would have tuned it properly and not thought twice about it .
    cheers to all
  4. gothicguy64

    gothicguy64 Member

    all that cost saving work ...

    i hope you are aware that there are better carbies an afterstock been sold here in oz ...


    mines a dellorto clone hp2 billet head coated piston 50cc
    billet inlet um billet clutch

    try reading what ppl are using
    ohhh yes there allso the wellbro

    syd :detective:
  5. motorpsycho

    motorpsycho Active Member

    that was good thinking on your part, and it was a free fix (other than your time).
    sure, you could buy an aftermarket carb and bolt it on, but what fun is that? lol
  6. Biker

    Biker New Member

    Thanks for the comments guy's,i've read most every post on this 2 stroke forum,and the Dellorto yes would be my first choice if i wanted to go down that route,and would have if this fix hadn't solved the problem.I liked the angled cable adjusters too,which i was going to pinch for my '05 Royal Enfield 500.