2 or 3 port PKXL cylinder

what is the difference and how do I notice?

No, if you have correct tools and enough time to do a good job…! You need a „Fräskopf“ which you use in connection with an electric machine which makes in rotate… I don´t know how to explain that in english, but I don´t mean a drill…
And: You have to disassemble your engine completely…

Manuel

Smallframes sind die geilsten Roller!

Original von Manuel: Of course! You have to differenciate between an open 3rd port and a 3rd port which is closed at the bottom of the cylinder. You can tune further when you open up a 3rd port in your crankcase, which fits exactly to the size of your cylinder-port...

Manuel

Smallframes sind die geilsten Roller!

my vespa is an 1983 pk50xl… it problably has 2 ports then. is it difficult to make an extra port in the crankcase?

Original von Manuel: Never heard of that, sorry! Where in Holland are you from? In Germany it´s absolutely no problem to find such an engine...!

Manuel

Smallframes sind die geilsten Roller!

im from the achterhoek, thats doetinchem, nearby emmerich.

Of course!
You have to differenciate between an open 3rd port and a 3rd port which is closed at the bottom of the cylinder. You can tune further when you open up a 3rd port in your crankcase, which fits exactly to the size of your cylinder-port…

Manuel

Smallframes sind die geilsten Roller!

hmm, to change the krukas [:)] on a vario scooter it was a hell of a job… so maybe i should keep std. transmission, but top speed would be terribly low then, right?

Right, a maximum of 70kmph, and a cylinder 85cc and higher does not work quite good with std. transmission because it rotates and rotates (you know what i mean) but transmission is much to short! Quite bad for the condition of your cylinderkit.
Alternative for you: A used PK125XL engine. Mostly between 200 and 220 euros, Vmax 90-100kmph, BEST quality! And if you want more, here you can drop a Polini 133 for example right out of the box. 125cc std. engine includes 19/19 carb and 2.54 transmission, exhaust looks like original 50cc-exhaust.

Manuel

Smallframes sind die geilsten Roller!

Original von Manuel: No, if you have correct tools and enough time to do a good job...! You need a "Fräskopf" which you use in connection with an electric machine which makes in rotate... I don´t know how to explain that in english, but I don´t mean a drill... And: You have to disassemble your engine completely...

Manuel

Smallframes sind die geilsten Roller!

something like a dremel or so [:)]

is it difficult to seperate the crankshaft like with a variomatik scooter?

Never heard of that, sorry!
Where in Holland are you from?
In Germany it´s absolutely no problem to find such an engine…!

Manuel

Smallframes sind die geilsten Roller!

Hi,

you can notice the 3-port cylinder by the third port :slight_smile: Which is situated towards the front of the engine…

Manuel

Smallframes sind die geilsten Roller!

can I replace a 2 port cyl with a 3 port like a 75cc polini?

Yes, Dremel for example. Thats not perfect, but „for beginners“ and small modifications absolutely okay! What do you mean by „to separate“? To disassemble the engine? It´s not that different, but for the first time, I would do that together with a friend who has already some experience.
So or so, you have to disassemble your complete engine to change your transmission.

Manuel

Smallframes sind die geilsten Roller!

Talk to [email protected] - he has several PK125 engines on sale… Believe me, it´s best choice in regarding price and reliability. Acceleration and „Drehmoment“ (Newton, know what I mean?) is much better than on every 100cc-engine i rode so far - really!
Time 2 sleep for me, know.
See you and stay tuned!

Manuel

Smallframes sind die geilsten Roller!

Original von Manuel: Right, a maximum of 70kmph, and a cylinder 85cc and higher does not work quite good with std. transmission because it rotates and rotates (you know what i mean) but transmission is much to short! Quite bad for the condition of your cylinderkit. Alternative for you: A used PK125XL engine. Mostly between 200 and 220 euros, Vmax 90-100kmph, BEST quality! And if you want more, here you can drop a Polini 133 for example right out of the box. 125cc std. engine includes 19/19 carb and 2.54 transmission, exhaust looks like original 50cc-exhaust.

Manuel

Smallframes sind die geilsten Roller!

hmm, dont think it would be easy to find such an engine [:)] im a doing a litte browsing, and i find polini 105cc 5port cylinders. These cylidners require the crankshaft to be adjusted?