Smallframe question for curare

I need to call on your wisdom again my friend, today i bought 3 50s vespas at auction for about 2500 australian dollars (includes tax and freight etc) And i wish to sell two of them to fund building the third into the best smallframe i can. What i want to know from you is what you think would be the best and easiest modifications to do to the other two to improve performance (maybe 90kph) and handling yet keeping it as reliable as possible, and also to do this as cheaply as possible. I am wanting to build the scooters i am selling into bikes fast enough that i can sell to non scooterists as daily commuters, what cylinder kit and carb combinations do you recommend? Also will a pk electronic ignition statoe and flywheel fit a 50s at all? As i wish to convert these to electronic ignition for reliability. I am buying a malossi smallframe reed valve kit for 50 australian dollars

Is this setup any good for the faster scoot i want to build?

If you could give me a list of components i will need that would be great. So far i am thinking for the bikes i wish to sell maybe a cylinder kit (pretty fast but must be cheap and reliable) A repro ss90 exhaust (or expansion chamber if they are heaps better) Some kind of electronic ignition kit, A larger carb (what size do you recommend?) A new crank (again what is the largest stroke i can go to in a 50s?) And an uprated primary gear kit.

Of the three bikes, one has 330 km on the clock, another 8000 and the third 3000 would i need to replace all bearings in each or could i get away with just replacing the crank bearings (dodgy i know but im trying to save some dollars)

And lastly for my own smallframe i was thinking of using zirri parts, do you have any idea on prices and specs on these? I hear people talking about them alot but i dont know much about them.

Once again i gotta say that it is great having someone as knowledgable as you to ask this stuff to, as hear in australia there arent that many smallframes around let alone tuned ones.

hello ultraphine,

I will give you same more info on the alrady good advice of our friend Juank.

For the two scooter you are going to sell:

polini 102
carb 19/19 (main jet 82 , 85)
polini exhaust
24/72 gearing.

naturally if you want to have more you need crankcase matching and race crankshaft, but also in the basic set up is preatty nice and should get to 90kmh. So I would keep it simple.
Just be sure to get the timing right and correct spark grade. It is important.

For your FAST smallfram project:

Zirri kit
zirri exhaust
carb 33 keihin or 35 mikuni TMX
27/69 or if you are after top speed 24/61
zirri short 4.
full circle crank.
The cases has to be spindled (enlarged ) to fit this kit.

If you want to use the malossi reed it means you want a crank reed intake.

Then you either go for the exotic fabrizzi, on which I can’t tell you a lot but the cases has to be spindled to accept this barrel.

If you want to stay more simple get a polini 130 with Worb5 modification or with gran sport piston (but if you use this piston you have to shorten the barrel)
Then you can use, after the milling work, the malossi reed, with a special lip crank, with a keihin PWK28 or a Mikuni 27.

will update this later after you decide which set up you will prefer and which ammount of money you want to invest for.
Of course Zirri or Fabrizzi are a much more expensive way of tuning.


for the gearing:

if you use the V90 100 it is going to be too long with a Polini. They give you a ratio of 2,86 while the 24/72 give you a ratio of 3,00.

Pinasco 102 is a good kit but less powerful then the polini and it is more expensive so I would not think would be your first choice for what you intend to do.

Also, on the worb5 site i saw a liquid cooled poliuni rotax 127 kit for 199 euros, would it be possible to use this?

Also i think that i am only going to sell one for now, then build up the second with a polini 130 kit (is this cylinder inducted?)

so i guess that i will want to get the best performance possible from a polini 130 kit (preferably without needing to spindle the casings)

Which smallframe came out with a 19mm carb as standard? was it the et3?I hope so, cos i assume that it will be possible to get second hand carbs from ebay then.

Also what kind of performance is it possible to get with the dr 102 kit by matching the barrel to the casings and fitting a race crank? And after matching the kit to the casings, will it then be possible to later fit a polini 130 kit to this set of casings, or are the port layouts vastly different?

Also the gearing that you have told me for hte bikes i wish to sell, what do they come off standard? or will i need to buy off the shelf stuff? As you can probably tell i am trying to do the one i wish to sell as cheaply as possibe, so that i will have more money to spend on the faster one for myself, I am thinking of building it into an ss90 replica, although it doesnt have the same hubs (is it possible to fit the same kind of hubs from an ss90 to a scoot with pressed steel wheels?)

Also there is a dr 102 kit on ebay that is quite good value, is this a similar item to the polini 102 you mentioned? Because if possible i would like to do the first one i build as cheaply as possible.

Also the reed valve setup for sale (the one in the picture) is a three stud type will this fit a 50s or is it just for pk?

Thanks alot for your help, much appreciated, and sorry to be such a pain, but when i find a place where people know what they are talking about i try and use the resource lol

Basically I think you’ll need to lower you expectations on top speed.

What I’d suggest for the 2 „sellers“ is a V90 primary,a 19/19 carb,Polini or Leo Vinci pipe and either a Polini or Pinasco barrel.I wouldn’t mess with the cranks.

The PK 50 flywheel,stator etc should fit fine on your bikes but make sure it’s 50 stuff only you use as the rest have larger crank taper’s as far as I remember.

I’d change all bearings etc as part of the deal.

As for your own bike?From what I know Fabrizi is generaly regarded as top-dog for smallframes these day’s but I’m sure Avenger can advise you far better than me.

Have a look here and here.

Cheers mate,

                  Looks like there is a pinasco 102 kit going too, what is the concensus on this one? I spose at least its aluminum which is a plus. Also is it possible to use 22mm carbs from old lammies on smallframes or arent they set up well enuff?

Amazing how much gear there is for smallies on germanies ebay though.

Cheers fellas,

It amazes me how much info i get from this site, I bought a alu. pinasco kit off ebay for 25 euro last night so that will be goin in pretty sharpish, now all i need is an xl2 clutch a new carb (there is a 20mm dellorto goin for 20 nicker in a coupla days with manny and a sports filter) Plus i need to do the gearing as well, so a primary gear kit is the clutch part and a gear that sits on the end of the crank, is that right?

Leaving aside your kit question’s (which I’ll leave for Curare),as I remember the entire Primavera and PK 125 range used the 19/19.Apart from the ETS which used a 20/20.

Reading between the line’s,Curare doesn’t rate the DR’s,same as me.However,as a cheap kit to move on it will suffice.I wouldn’t use one for myself,you’ll be dissapointed.

I wouldn’t worry about the transfer’s as the Polini is almost certainly larger.

Off hand I can’t confirm we are talking about the same primary’s but I suggested the V90/100,perhap’s Curare will confirm this.Or not.;D

The V90/100 primary should be readily available.

You can change the hub’s no problem with new backing plate’s etc.

If building a very high performance machine I would recommend using PK100/125 fork’s with a disc brake set up too.You lose the look but the differance is phenominal.[:smokin:]

I’d forget about old Lammy carb’s,they’re total shite.[;)]