Help With Jetting Please

Hi All
Hope you all had a good time in Great Yarmouth??

Could someone please help with the jetting of my S1 standard carb which is fitted on my P200? Also what degree for the timing would be appreciated too?


I have fitted to my P200, a 60mm Full Circle Crankshaft, a Pinasco 215cc head, barrel and piston (this has been matched to the cases with the aid of a dremmel and has got 3mm gaskets as needed), a Cosa clutch, a T5 short 4th gear, a PM Tuning Evo 2001 exhaust pipe, a HP4 Flywheel along with all new bearings oilseals, gaskets and nuts and bolts.

With the above setup, would it be of any advantage to change the carb to something bigger? (please bare in mind fuel consumption when offering any answers)

Cheers for now BIG N

[:dance1:] [:dance1:] [:dance1:] [:dance1:]

Hi Dylan…phew…what an answer you gave me!!..LOL
I have a good friend who is far more technical with regards to the setting up of Vespa engines than i am. He has the same set-up on his engine and has a rotary valve fitted and can achieve 94mph…he is now changing his back to a S1 carb as his fuel consumption is very heavy.
With regards to my head, piston and barrel it is a Pinasco 215cc kit…with regards to the 3mm gasket this is at the top end, i presume you would say this is correct ??

In your reply you said i would most definetly need to change the carb…what, in your opinion would i be better off using? what size and make of carb and reed valve would i be better off with?

Just one more question…what do you mean by „chop out“ the plug?

sorry about the non-technical answers mate…i`m just looking for some good advice…which you seem to be able to provide
Cheers BIG N

[:dance1:] [:dance1:] [:dance1:] [:dance1:]

Hi Dylan,
Thanks again for the help mate.

ive just spotted the mistake in my first post......i havent got a full circle crankshaft at all…it is a long stroke crankshaft.

I`ve been talking to some other scooterists and funnily enough, they have said exactly the same as you with regards to jetting the standard 24/24 S1 with the Pinasco 215cc kit and all the other parts fitted, use a 125 main jet and work my way down.

Thanks for the advice on „chopping the plug“…this i will easily be able to do as we have a nice long bypass literally 3 mins away from my house…so you can guess were i will be opening the baby up! (old bill permitting…lol)

So after all of this text, any idea on the degree of timing?..(yes more questions …sorry)

With regards to seizing up, that is the absolute last thing i want to do…one of the lads in the club (Blue and Gold SC, Kings Lynn) had a partial seizure on a short rideout the other week, when he was running in a new Malossi 177 kit…and guess who was right behind him at the time? got it …little ole me!!..evasive action required right sharpish [[:O]] …so we went for a qiuck pint to calm his nerves!..LOL [:drink:] [:drink:] [:drink:]

Anyway , thanks again for the help…no doubt i`ll have some more questions sooner or later…(sooner i seem to think !)

Cheers BIG N