Main Jet settings

Hi All,

Can anyone take a stab at the main jet settings for a PX125 Disc with Polini 177 Kit, SI 26mm carb and a Polini exhaust.

Also, do I have to take the air connector and BE jet out of the 20/20 carb and put it in the 26mm carb or do I just install 26mm carb and use different main jet.

Thanks,

Brian.

Regards,

Brian.

yes Brian i used all the jets that came with my carb.

Hi Brian, just got back from Revival Scooters where I had my bike set up on the dyno and I am well happy. Here goes; it is an LML 150 (PX 150) motor, standard apart from; Simonini pipe, 26mm SI carb with all the jets that it came with (120 main, air screw all the way in then back 1 and a half turns, all the others as it came) timing set between 1 to 1 and a half degrees retarded (did it by eye so not sure on exact figure). It was running fine upto 80/85kmh then started spluttering upto 95kmh. The first dyno run showed it was too rich and only making 8.7bhp at peak power, but because of the stuttering and coughing it was only really usable at around 7bhp, the timing and jetting were actually about perfect but the problem was the Indian standard airfilter (it was too restricted by the amount of gauze in it, when you hold it to a light you cannot see through it, it is so thick) so they took off the filter and it ran like a different bike, they found me a second hand Italian filter, and fitted it, and it ran cleanly right through the rev range and made peak usable power of 10.1bhp at 68.7mph (about 115kmh). On the way home I was doing 100 to 110kmh into a strong headwind and it went off the clock at 120kmh on a clear level road sheltered from the wind. They told me that the LML barrel ports are smaller than Italian ones to restrict the performance, so that will be my next step, but I am going to try it as it is for a while to see what the improvement is and finish running it in ( this was dynod at 1184km so I still have 800km to finish running her in). They showed me a demonstrator of a PX 125 with a Malossi 166 kit, 26mm SI carb and Simonini pipe (basically the same stuff as I already have but with the 166 kit on) and they dynod that to 17.4bhp and it is still a reliable tourer as they have built it for road use, not as an out and out racer. MMM christmas is coming so I may be tempted. Basically, I now have a restricted 150 motor that is putting out the same power as a standard PX 200, just by sorting the carb and pipe.

Hi Brian, I have a 120 main jet in my 26mm carb, I have retarded the timing a little but that is all.

OH YES, THAT IS WITH A STANDARD PLUG (WELL AN NGK EQUIVALENT OF THE STANDARD PLUG AS I PREFER NGK TO THE CHAMPION IT CAME WITH).

Adrian,

Did you use the air connector and BE jet that came with the 26mm carb?

Cheers,

Brian.

mine is on an lml 150 with nothing but a simonini pipe on, it is not perfectly setup yet, i am still running her in, i will have it set on a dyno to get it perfect (jets and timing) i will let you know when it is done.

hi Adrian, what is your set up then…is it much the same as mine and do you have the porting done.

Regards,

Brian.

Thank you very much for the info…

Regards,

Brian.