Modern Vespa

Malossi came out with a new Big Bore kit for the Vespa GT200. It increases the displacement to 218cc, the biggest to date. They also have a kit that includes the Head, Cylinder kit and Cam that is cheaper than the old 209cc kit, which is discontinued. All the 209cc cylinder kits for the GT200 are discontinued.

218cc and more than 22 horsepower. I know what I'll be doing this Winter.

Here is a link to information about the new kit, with Dyno results.

http://storage.malossistore.com/news/pdf_prodotti%5Ccilindro%20diam.%2075.5_001.pdf

Just rebuilt my engine in my GT. Malossi crank in it now, readded the malossi camshaft. Still running the 210 kit with the V4 head. Looks like soon enough I'll be spare parting the 210 cylinder and installing the 218.

I'll have to pull out my dyno charts for my run to see the actual claimed difference.

So here is the Malossi dyno chart:



Here is my dyno chart:



Mine is Malossi 210 cylinder kit, V4 Head, Camshaft, Malossi CDI, and lots of other little mods.

Runfile_006 is a stock GTS 300
GTV 250 is obviously what it suggests a stock GTV 250.
runfile_053 is my GT200.

Torque is about 2 ft-lbs less comparing my GT to the stock GTS, but HP is where I make it up with just under 1 HP more than a GTS. So top speed wise I will beat a GTS, and have... it will outrun me in acceleration though.

So what I see what from their claims is a 6 HP increase from a stock GT 200 with the 218 cylinder, head, and cam.

Of course it is hard to compare the results of their dyno to mine as different dyno's are going to have different numbers resulting... but I would figure maybe a 4 HP increase between the two cylinders not terribly bad for $330 and a couple hours of my time.

edit: Looking at the charts again, its quite obvious their dyno is either measuring results differently than mine or they are inflating the numbers. You'll notice their stock GT reading is 16.6 HP and my modified GT is 17.6 HP so unless the cylinder, head, and cam they make results in only a 1 HP gain the dyno results vary. The true test will be to install the 218 cylinder on mine and do another dyno pull at the same shop on the same dyno to see the difference that results. My money is sitting squarely on adding at least 3-4 HP with than 8 cc increase.

Tech, you are boldly going where no man has gone before. Great charts. Too cool. Great work you are doing.

are these kits available in north America yet?

What upgrades have you doen to the variator and clutch setup? I just installed a 210cc kit w/ 4valve head and cam. My dyno run came up to 17.8-ish. I have to find the actual graph. I think if i rework my transmission setup, I may be able to get more power ATW. Is that correct? And if so, do I increase weights, or lower them? Right now it seems like its slipping a bit, but when it grabs and goes,...it goes!

Reviving this zombie as I know Motovista still roams this forum and I'm curious if he ever installed this kit and what his results were. Seems like Techenigma thought Malossi's claims a bit overblown but wasn't able to do perfect test to determine for certain.

The best I ever did on my GT 200 with the Malossi top end kit was to get the speedometer needle so it just touched the edge of the code light, riding on a flat road. I did change out the primaries and secondaries and it still wasn't hitting the rev limiter. Just ran out of horsepower.

So you're saying it was a pretty great addition, eh? Any downsides? Was that the only mod you did or did you make other tweaks as well?