I need help!!

Hello everybody,

I´m a new member. I´m from Seville (SPAIN) I´ve been reading this forum for a few days now and I would like some opinion…

I have 2 vespas: a PK 80S (1984) Pollini exhaust, original engine,

and a PK 125S (1986) this one is all original.

I am having both vespas painted and would like to prepare the 125´s engine, exhaust, carb, clutch…etc… What do you recomend me to do?

Regards from a new member from Sevilla!!!

Can´t wait to hear some news from you all

Isaac, very brave to go with only one persons ideas, but for a road motor this set up has a proven record. To keep your initial (first) costs down, Get the parts to do the internals so you dont have to split the cases twice, get the cases tuned symetrically to the cylinder so that it can be reversed at a later stage. Reed valve to the cylinder, but save money to start and buy a polini/ cheap exhaust. By all accounts, the expansion chamber will be the single most expensive item, ( and it may even need modifying to suit your engine/style). Ultimately justified for the power gains. I will go through the parts and check them out for you. Do you have scooter tuners in Seville to do the casings and cylinder and reed valve?

Ho oh Beerace,I think it’s time to show us a pat of all your knowledge about all this, take some pictures and show us how to do step by step, it’ll be great, guy!!![:rotate:] [:D]

… forgot,

the only thing could save you same money is the full circle crankshaft. I tryied few times comparison with standard one and I don’t think it is worthed. But this is personal. And HP 4 flywheel I bought it even though somebody here told me the downsides that I found to be true (less cooling then PK flyweel). For normal street use I would keep the PK one. You will loose some response but better cooling…it is your choise.

[:roll:]

Mikke, I have a PK125XL here waiting to have the full monty. Some parts I have, (malossi kit, hp4 flywheel etc.) But, as this engine will sit in the workshop until someone buys it, or I sell my other scoots and run my SS90, I cant commit the finance to it. Im not a dealer/buisiness yet, and disability only goes so far (food, mortgage etc.) Otherwise GREAT idea. Sorry buddy.

Isaac, parts listed are; malossi cylinder,15030000 ; Crank, 45063000 ; Primary gear-up , 15320000 ; 4plate clutch, 93490000 ; hp4, 50010000 ; THEN you need to decide whether to reverse cylinder or not, bear in mind that youll have to fabricate your own inlet from reed valve to carb, and use a bigger carb, if Not reversing cylinder then use the malossi carb/reed kit, 15120000, and either use polini exhaust off you 80 or expansion 22011 (jim lomas copy of taffspeeds exhaust)[dont go for vsp1 pipe, they are terrible build quality, or pm, too expensive jl as good.] If you ARE GOING to reverse, then use zirri exhaust, 404900, but may need added metal to parralel section. Dont forget bearings, seals, gear selector and uprated spring, gaskets, tuning to cases and cylinder. Not cheap, whaddya do win the lottery?? Oh, and use 8mm barrel studs not 7mm as standard.

Original von BEERACE: Isaac, your engine design/ layout is different to the early 150/ pX type engines. Every "Expert" has their own ideas on tuning. With that in mind, basing tuning the PK125S engine, and cost no restriction, reliability combined with acceleration/ top speed, my opinion is as follows; PK 125 XL Full-circle crank, Malossi 136cc cylinder kit, TUNED, PORTED and REVERSED, along with cases. Cylinder mounted reed valve, 24>30 Flat-slide PWK Carb, One-off/ quality Expansion chamber (biggest % gain per component per Euro). Primary drive gear-up, 4 plate clutch. Lightened PK XL / HP4 Flywheel. Very fast, good acceleration, reliable, EXPENSIVE TO BUILD. But then again..........

Beerace, Your advice sounds good so I´m going to do it!!!..
…but I have a big problem [:@] . My English for technical words is terrible.

I´ve been searching for the products that you recommend and I´m not sure if what I found is what you said, and also there´s some that I can´t find…

Following is what I found:

PK 125 XL Full-circle crank
Full circle crankshaft Vespa Art.-Nr. 45063000

Malossi 136cc cylinder kit
Racing cylinder 136cc MALOSSI Art.-Nr. 15030000

Cylinder mounted reed valve
Manifold reed-valve POLINI PK, Art.-Nr. 21502310

24>30 Flat-slide PWK Carb ?

quality Expansion chamber ?

Primary drive gear-up ?

4 plate clutch
Clutch V50/PV/PK, reinforced, Art.-Nr. 93490000

Lightened PK XL /HP4 Flywheel
Flywheel special HP4 PIAGGIO Art.-Nr. 50010000

If you don´t mind, It would be of great help if you can tell me if what I´ve found so far is ok?

As you say… IT IS EXPENSIVE but I trust the result is going to be great. I will send photos.

regards,
Isaac

hello,

I also have a PK 125 with almost the same set up only small differences here and there.
Yes, it is fast, it is reliable, it is not cheap but you won’t regreat it!

[:roll:]

Isaac, your engine design/ layout is different to the early 150/ pX type engines. Every „Expert“ has their own ideas on tuning. With that in mind, basing tuning the PK125S engine, and cost no restriction, reliability combined with acceleration/ top speed, my opinion is as follows; PK 125 XL Full-circle crank, Malossi 136cc cylinder kit, TUNED, PORTED and REVERSED, along with cases. Cylinder mounted reed valve, 24>30 Flat-slide PWK Carb, One-off/ quality Expansion chamber (biggest % gain per component per Euro). Primary drive gear-up, 4 plate clutch. Lightened PK XL / HP4 Flywheel. Very fast, good acceleration, reliable, EXPENSIVE TO BUILD. But then again…

Mikke, If you read my post on the auto’s board, youll see where the proceeds from my last exhaust sale and tuning jobs went. Just a few more bits to do to it and itll be finished. Then Ive my 210 to finish off (still waiting for a crank pin!), then my TS1… The list goes on doesnt it. In between, getting ready to start producing, (about 3-4 months at the rate im getting mobile)

Thanks Mikkke and Beerace for answering so fast!!

[:rotate:]

I think its very similar to the 150cc, try to read some older post, I own a Malossi 166 onmy PX150 with a Sip Performance exhaust and it runs very well, I need a carb (30mm), don’t worry some experts are going to aznswer you soon!!! ;D ;D ;D

No need to be sorry, guy, it’s just like most of us. I have a 1965 180 Super Sport and I bought it three years ago and I’m still waiting to buy all the parts needed to restore it so let’s dream together. I have in my mind to open a little business too because here we don’t have many tuning parts sellers and I think it would not be a risky business. So let’s continue our way to this life we live. Keep on going Beerace the road is long! [:rolleyes:]

beerace, no, I haven´t won the lottery but I have been saving some money in order to do one of my dreams: to have a super-prepared vespa!!!. I think the time has come to do it and enjoy it as I work on it and see the final result!! I think it´s going to be worth it!! I know it´s expensive but there´s worse things that people waste their money on, don´t you think?

It´s a shame that you don´t live near here in Spain, but if you sometime come near seville you are welcome to see the vespa that with your help I built!!

thanks again, and I will send photos

I agree with both comments from curare, and add that the plastic fan on the hp4 also comes loose!!! Not good, but would expect a degree of preventative maintenance that would identify this before catastophic failiure. As you have to buy either flywheel the PKXL flywheel is more of a fit and forget iyem, the hp4 is not. Also to add a standard PKXL crank will have slightly better ballance than a full circle, and power loss is minimal but again, you have to buy one or the other so giving you power version. Click on „BEERACE“ to e-mail me, Isaac.