YZ125 H 1981 Carburettor Jetting

[DJRacing]

Shouldnt the YZ125H have a 34mm carb and gearing of 48/12

If you are running 42/13  I'm surprized if it could climb any hill.  The YZ125J '82 model was over geared by at least 2 teeth so the 46/12 was changed to 48/12 and even then still felt over geared.

[oldyzman]

The gearing seems like it should have heaps of take off potential.
Lozza -tell me more about more low down power on a 125, i am all ears, u talkin pipe, port timing...
Regards Brett

[Lozza]

Yep all those

[Ji Gantor]

So is there no one on the forum that has a stock standard YZ125 H 1981 that blasts off the line that is willing to share their jetting?

Ji

[vandy010]

this is what my manual says for a YZ125H
                VM34ss
     I.D. mark = 4V2-10
       main jet = 340
    Needle jet = P-8
            Pilot = 80
    jet needle = 6F21
  clip position = 4
slide cutaway = 2.5
     float level = 23.4

[Ji Gantor]

Thanks Vandy,
That is what my manual tells me for a Canadian bike.
The US and Aussie bikes had a 32mm carb.
The jetting was selected for a colder climate and thus the main is at least two sizes too big.

But it would seem that no one has one that blasts off the line.
I spoke to a really cool guy at Coles Creek and he told me that a fellow called Gash back in 1981 wrote a piece for motorcycling Queensland on how to set the H up.
Mr Gash was a sponsored rider for Moorooka Yamaha at the time.
Does any one have a copy of this article?

Ji