Modern Vespa

I currently purchased a GTS 150 3V i.e.

Pretty happy with the ride and looks but not satisfied with the engine performance. Upgraded the variator and clutch but it still felt sluggish.

What I am looking for (if it makes any sense):
- Accelerate fast and smoothly from 0 to 85kph.
- Cruise between 90 - 110kph without making the engine scream.


Need your knowledge and suggestions, please.


Would it make a huge difference if I upgrade to a Polini 177 or Malossi 185 considering the small cc increase from 150cc?

With a difference of 8cc between the tuning kits, would there be a big difference in performance?

And if I purchase the kit. Besides port and polish, ECU and exhaust upgrade, up gear, what else would I need?

Your help is greatly appreciated. Thank you!

Couple informative threads on kitting the 3V 150:

Malossi Big Bore Kit on my 946!!!
Malossi big bore tear down for 3v

You don't need to port and polish, and don't need to do anything to the ecu other than installing the forcemaster if you go with the Malossi kit. Then go with a good pipe and get the right weights in your variator. Your bike is massive for the engine, and if you install an upgear kit without the right variator weights, it's going to be even slower. Upgear kits work well when you have too much power for the stock gear ratio. Until you get the horsepower way up, your bike is going to struggle to pull the upgear.
Go with the Malossi top end, a good aftermarket pipe, and find the right weights for the variator to make the scooter do what you want.

Thank you for the link, bluecloud.

Motovista, thank you for your suggestions.

I am still unsure yet if an increase of 30cc would make a huge difference.

I put the Malossi 190 kit on my leader 150 along with a GPR pipe and Polini upgear. I also changed weights to 12g in a Malossi variator.

My top speed increased slightly, I can now hit a gps read 68 mph on a flat stretch.

Where I really notice these mods is when accelerating from 0-55 mph almost effortlessly. Once at speed, I can keep the throttle at barely 1/3rd and I can hold 50mph very easily. The real world driveability is greatly improved with an increase in the torque.

The 3V engine will likely behave very similarly to the carb'd Leader 150 to the same types of mods.

How would an air cooled leader engine perform in a GTS body? That's what the OP has, so gearing is going to be a bit trickier than in a modern smallframe.
It's not just the extra 35ccs that makes installing the Malossi kit worth the money, it's that combined with an increase in compression that makes the real difference in performance. That's why the 200cc OEM Leader kits haven't worked as well as the smaller Malossi and Polini kits for the air cooled engine. As far as the choice between Polini and Malossi, Polini usually hits the market first, but over time people end up installing Malossi kits, because it's a bigger, more complete and better performing kit.

Thank you for your insights CrazyCarl and Motovista. Greatly appreciated.