Pinasco 177cc cylinder/piston scoring

I have a scored berrel and piston on my Pinasco 177cc big bore kit fitted on my PX125. I bought the kit last year and used the scoot for a couple of months problem free before I realised that the on going problem with gearbox oil dissapearing (seperate issue me thinks).

Anyway, I decided to order a new crank, bearing and seal set in the hope that it will rectify the oil issue. To my shock the pinasco kit seems to have a score on the barrel and piston. Now this was a bit of a shock becuase the scoot had never seized during the time I had ran the kit, and I am a little concerned that because the bore is chrome plated, it could have done some irriversable damage. the kit cost me £160 (185Euros) so I am not best pleased! Has anybody else had any issues with Pinasco kits?

Also, I have always been under the impression that alli cylinders with chome plated bores had to be replaced if there are any scoring, is this true?

Hi,The kit should be ok if the scoring is not too deep, most kits will get scored at some stage and still run ok. 3% oil shoould be used instead of 2%, autolube will supply 2% so add 1% in the tank. A standard carb(si24/24e) from a px200 will compliment the kit nicely along with a sito+ exhaust. Jets should be changed to suit and ignition timing can be retarded slightly to cool the motor. Chrome or Nicasil lined barrells can not be rebored and need replacing when too badly damaged. Remember to be nice to your kit till the engine warms up properly (10-15mins)

You are scaring me! I just bought a Pinasco 177 for my 05 PX 150. Just wondering what carb and exhaust setup do you have? I am a newbe and still learning, I have been told on my posting that a SI 20/20, sito plus and unmodified engine setup will not have sufficent cooling. Its' been recomended that 24/24 is the best setup. Overheating maybe your problem. Wait... No BS, just a few minutes ago, I just got my parcel...Bye.

Hello rendersonique,

believe it or not, extra oil added to your fuel (by yourselve or your gearbox [8-|] )

Will actually make your fuel mixture more lean, thus your engine will run hotter.

The best thing in this respect you can do for your Vespa is mix your fuel yourselve (sip full synth is as good as Motul full synth, if not the same oil...)

When you use a good quality synth. oil. you can also then forget abouth cleanning piston and exhaust ports for a very very long time (depending on driving conditions)

What carb. are you using? the standard 20 mm. Si or a 24 mm. Si? again a 20 mm wil cause your engine to run hotter (combine this with an allready leaner mixture and things keep adding up)

More oil in your fuel is NOT neccecary a good thing.

So yes your damaged oil seal could also be (partial) responsible four your cylinder overheating/scoring.

Just clean the cylinder with very fine sandpaper, and if neccecary change the piston rings, and things shoud be fine.

I've been running a pinasco 177, with a 24 mm Si carb and a standard exhaust for over 3000km now, and so far no problems.

(motul full synth oil, ngk sparkplug BR8 something, standard 24 mm. jets in carb.) (both holes in airfilter above jets opened)






Hi Mchabot

Marcel, Just wondering, what size are you using for atomizer and main jet. Also what % mix are you using.

Best regards rudy812