PX200 stage 3/4 with SiP Road exhaust - SiP advice please - La Rocca maybe?

I have got a PX200 1997 elestart and the following work / parts have been done  /added:-

MMW high compression cylinder head

SiP Road exhaust

Mazzuchelli Race Crankshaft

Exhaust port raised by 1.5mm, and widened /centralised by 6.5mm ( 2 + 4.5), transfer ports cleaned and very slightly enlarged. Piston windows cut to suit, similar to Autisa spec.

Standard Si24/24E carb with air filter ( 3mm hole above jet stack)

21 deg timing


You've guessed it, I am hoping for advice as to likely jetting - no porting has been done to the crank case inlet at all. I currently have got a 132 main in there and have only run the scooter for around 25 miles at moderate speeds so far to shakedown the rebuild and do all the re-torques etc.


definately! keep me updated. and, much luck.



argh! you do realize that if it were a horse, you would have to shoot it. who's the supplier? - i don't ever want to deal with them. and i vote, don't give up. you are in way way too deep to give up now. i'll try to send some more positive thoughts/energy your way. (or maybe you would be better off if i stopped?) keep me updated.

lots and lots of luck! heggie

Have got a 52/140 and a 50/120 so should be able to find a compromise.

I'll let you guys know how it goes ok ?

The casings are repaired and tomorrow we build , the Sunday we thrash [6]

[6] LOL Heggie it means exactly the same thing here mate !! [6]

The cylinder kit is broken in and proven already, its given me such hassle that I figure it deserves a thoroughly harsh thrashing !!  . . . . . . . . . . .ok, ok I'll play nice to begin with but day 2 is open season LOL.  [<:o)]

[quote user="Hamer"]

Devil LOL Heggie it means exactly the same thing here mate !! Devil

The cylinder kit is broken in and proven already, its given me such hassle that I figure it deserves a thoroughly harsh thrashing !!  . . . . . . . . . . .ok, ok I'll play nice to begin with but day 2 is open season LOL. 


your px200 will thank you for waiting until day 2 for the thrashings to begin. let me know how day 3-33 goes. it's been fun. good scootering to you my friend!

later, heggie

Its done, needs some small adjustments (gera cables etc ) and the carburation is going to be trial and error but we have transport . . and without tempting fate, it all seems good.

anyone ? SiP techs ?  . . . . . . . . . . . .[8-)]

Thanks mate, the orange P200E was the love of my scootering life, I've had all sorts of Vespa, Lambretta and BSA scooters but only one stood out like the P2 - I hope this latest one will fill the gap and grow on me a little.


Tech Guy - I can't see that size slow running jet listed ?

Its just as well I did not go and buy a full blown kit for the bike as well mate, at least this way I had some cash to get the casings in ! I got lucky today and bought a set of NOS electricstart P2 casings for £170 sterling, so it could have been worse. I need the reliability as its going to be my daily transport and also my plans for another tour of northen France are too far advanced to pull out now [;)]


Many thanks for your support mate, I am rebuilding into the new casings as we speak. Will let you know ok ?



glad to hear you're almost back on the road!(the new px200 sounds great.) - take it easy with her. and, R.I.P. orange px. [:'(]

later, heggie

cool. if that don't work, maybe try a 50/140. (sip has that size.) later...



as far as the ratios go... when i had my stella built up with  DR 177cc kit and a sito+ exhaust. the only time i really needed 1st gear is if i was starting up hill or with a passenger. i knew some people that had the same DR/sito+ set up for use with a side car. and, i have the lml 200cc engine in it now. either engine i think i could run a 20 tooth clutch and a T5 4th gear to lower the ratio before the 12" wheels raise the ratio. and i think it would be alright. (power/gearing wise.) plus, SIP is selling the conversion and mention nothing about the need for more power in the "tips" part of the part/item description. (though i know it would need more power.) (plus, vespa was running a 200cc, a 250cc and a 300cc 4stroke to power the 12" wheels on the GT, GTV and GTS. ) also, you can buy a modifed lml star 150 at www.vivoscooters.co.uk with their 12" conversion (their conversion dosn't use SIP parts, i asked them.)brand new and ready to roll. (if only i lived in the UK.)

i know SIPs "glorious basterd" is running a tuned lml 125cc engine and i've heard it is very fast. i also know that it's using a SIP rev. counter/speedo but i have no idea how (with what parts and part numbers) they got it to work correctly. (or if it even works correctly.)

anyways... a 12" stella is my stupid dream. i'm just having trouble finding every single part in need. and like i said - not to modify the body, not the parts for scooters other then a 09 stella 2stroke, just the parts with part numbers so i can have a fully functioning stella 2t with 12" wheels (rear drum brake econo version) and a working (in m.p.h.) speedo.

thanks for listening hamer. later, heggie

Also carb , airbox and crank case external inlet port matched


good luck trying to get a sip tech to help - i never seem to get answers. maybe they're just trying to catch up. :) i've been trying to get a complete parts list with part numbers for the gts 12" conversion for my stella 2t and more info about the water cooled p200 head since before the internet was invented.

www.scoot.net has a jetting base that you could try. or, you could post something over there.

do you have a big bore cylinder kit on it? i didn't see that listed?

hope that points you in the right direction. later...

p.s. i love the orange on the px!


Thanks for the kind comments dude, the orange PX was in its original Piaggio Red (go figure eh) and died a sad and horrible death last year almost taking me with it [;)] and I am now just about back on the road with a 1997 Electricstart PX200. The cylinder is stock but has been ported and the piston cut to match. Its tuning on a budget but should be good for a genuine cruising speed of 70mph and a top end of maybe 77/78mph.





Tech guy,

I thank you for the guide

I have been adjusting and have got quite near to that spec so am really happy with that.

danke shoen,



i didn't see a 55/140 either. only found 52/140 # 40265214 and 50/140 # 40265014 .

good luck. heggie

2 hours of welding and 3 and a half hours on the CNC Mill, the casings are being fitted with the bearing in the morning and then either the laughter or tears or both can begin LOL