Update:
OKO26 carbie (non-standard item): Great. Very snappy of torquey power in low and mid revs. Sensitive to air conditions. In less humid conditions I had to go one clip richer (than middle) on the needle, and also back to the richer 102 main jet. See also:
http://www.miniriders.com.au/forum/tech-talk/16320-needle-position-lifan-140-a.html#post153171
Suspension rear: Shock (DNM) is going in for a re-valve. On rough tracks, engine HP is fine at present, and the shock is the limiting factor when accelerating or braking in bumps. I played with the clickers but I could not find a good compromise. The problems with the DNM shock are: a) The dampening is not progressive according to where shock is in its stroke. b) The shock's dampening is inconsistent as it heats up, so the rear ends becomes a bit unpredictable. I shall get this fixed by a tuner.
Suspension forks: I am now using 290ml of 7.5wt fluid in each fork leg. For more bottoming resistance. The forks really need a re-valve too - for serious racers. eg. I can add oil to stop bottoming, but the top of the stroke then hardens up too much as well. I can use thicker 10wt oil and the action feels nicer, but on repeated bumps the oil cannot flow through the rebound circuit quick enough to re-pool down the bottom. With thinner 5wt oil the valving sees to "air out" or cavitate. Don't read me wrong. These forks are excellent value. I'd love to feel the diff against best retailed Marzocchi's or Fastace forks.
Race CDI. Died on me. So back to std. Easier starting with stock CDI. Race CDI did seem to have a little more go at high revs, but nothing substantial. The race CDI was causing too much starting kick back - probably because it was a dud unit and/or the wiring on my bike has a problem which that unit did not like.
Cam: I have an Akunar A1 6.7 mm lift cam. Not installed it yet. This coming weekend is my last chance to ride before I go away (work) for a few weeks. Also got an A2 cam being sent to me now. I had a peek at the stock cam grind, and the A1 is similar in style but more duration and lift. It'll be interesting. On rough tracks a strong bottom end engine is great on this bike. A LOT of fun.
Oil slinger: I tried the steel one again. I cannot go back to the steel unit again. It kills the accel. So alum slinger for ever on the Lifan 140 for me. If my crank breaks due to fatigue flexing and the lack of weight on one end (no IRK), then so be it. I'd rather the joy of faster engine spin up, and buy a new motor if I kill it. There is no point revving this engine a lot (troque drops off), so I guess I'll be fine with the alum slinger.
Tyres: I put a Kenda Millville on the front 14" wheel. On medium hard surfaces, I'd say the Innova had more traction. The problem with the Innova is that the tyre carcas is 6mm smaller all over than the Millville, so less tyre body/air/pressure support on impacts the rim can be dented easy with the Innova tyre on rough tracks. The Millville grip on medium/hard terrain is not good IMO, but it will do for now.
Air filter "snorkle": Working great! See also:
http://www.miniriders.com.au/forum/tech-talk/15882-air-intake-snorkle-2.html#post153170
Next: Forever learning how to ride it faster. Firmer seat foam. Shorter turn throttle grip.