Kit set up questions

Hi guys,

Finally got my PX 125 back on the road. Dell Si 24 carb, Pinasco 177, and Simioni. Had a real bitch of a problem with a stripped selector rod and cruciform and had to get a shop to sort it.
40 ish miles on and all feels pretty good… in fact it feels great, the torque is amazing and hits 40 with little on the throttle. A bit sluggish pulling away in 1st, ldle speed not quite right yet and the plug is quite oily but nothing too major. The mechanic got it running ok with a 111 main jet which is still in there.

1.Which way should I go on size of jet at this point?
2. Mechanic, was reluctant to change the timing as he felt keeping it at stock 18 was more reliable. Should I change it or not? What are the implications of leaving as it is?
3. Running in speeds. What would you reckon would be the most I should push it to at the moment?
4. Plug chops. Is it WOT in 3rd and then kill the engine? And how long should I continue running easy before I do a chop?

Thanks in advance


I know that the Pinasco website recommends 20 degrees for the 177 kit.


no, if you leave timing at 18 would not harm your engine, but neither will harm it if you go to 20 (+ - 1°).
It will go better. That’s it. If your carb is set up as it should don’t be afraid. As I told you I used 18° in a much more tuned Pinasco 177 version and I didn’t experienced any problem.


the timing 18 for pinasco 177 is in my opinion not enough advanced.
I used 18 with Pinasco +longstroke + 2,5mm base gasket + malossi reed and 28 carb.
So you can advance timing if not your engine at low rpm will be have a little "sluggish response.
I would go 20. And check the spark grade : W3AC o B9. Is is important if you adv. timing that the plug is of this grade.
And be sure it is right with strobo.

The chop.

in 3rd about 10-15 sec. if you are really sure you are already running a little rich. If not put a jet to begin with wich you are sure you will be rich and then go down. It is important.
It is better when you do the first chop to have an oily spark then a white one. You could risk sizeing.
When you check the spark colour look inside not the collar.

You have to find a jet that will give you the bronze colour to your plug. A little oily is not good.

For running in please read the answer I gave you on Malossi 210 created by nonmank.

Thanks for that. Was worried that I may damage the engine if I left it. But then again, I was worried I’d screw things up if I attempt to change the timing… seen loads of postings that suggest it’s a subject that people have difficulty with. I think you may have given me the confidence to attempt changing it.

Thanks curare,

Apart from the response being a bit ‚sluggish‘ if the timing is left at 18 degrees, would it actually do the motor damage?


AS curare says follow his advice on running in!!!
I did whitby on a not very well set up p210 with timing well out, jetting well out and air correction well out as well and still managed to get home —just about.
i think if i had not followed curares advice it would have been a van job home with a seized malossi
i am just in the middle of a strip down once again to get the t5 fourth in and get the timing right.
thanks again all of you two stroke specialists who help us pretenders stay on the road
j[:drink:] [:drink:] [:drink:] [:drink:] [:drink:] [:drink:] [:drink:]