Modern Vespa

I have over 11,000 miles on my kit now with no problems whatsoever, including a 4,000-mile-long tour from Maryland to Colorado and back.

Still have the stock main jet, and it seems to be happy with that, although I may try one size larger just to see what happens.

60 to 65mph is a more realistic cruising speed over varied terrain and wind conditions, although a 65-68 cruise certainly is possible on flatter ground with light winds.

yes the stock belt suffers with heat stress, contrary to popular belief that the standard belt is better than Malossi, that I agree with but only on the larger GTS250/300. On the leader 125/150 I believe Malossi is the much better option and it gives you a slight upgear which is an added bonus.

hey guys got a needle inside my gear box i need to dismantle the gear box in order to get it out i know how to remove the rear wheel but need help on the brake disc and gearbox part

Can u use a polini primary up gear kits in my et4 190 with already installed malossi secondary gear upgrade kit???

Greetings:

I can see the thread is from the past, but here goes...

The secondaries you have replaced the small countershaft gear (let's call it #3) and the large one (#4) on the axle. The stock Large countershaft (#2) gear is pressed onto the aftermarket countershaft.

Now if you get the Primaries, the Clutch shaft (Gear #1) goes away along with the Stock (#2) you kept when installing the Secondaries. It should all work together, EXCEPT that you now have Taller x Taller, and I'm guessing something like a 4.5 to 5.5 : 1 overall ratio. This can be expected to make your 0-10 MPH takeoffs a painful, clutch-abusing ordeal, even with appropriate variator modifications. And without substantial power improvement, it's not certain that your engine will have the drive to max out the variator, which is important because that's where belt tension is highest and so minimum slippage. You may even go slower on top speed.

For the record, the overall Clutch Shaft to Rear Axle ratio on the U.S. ET4 150 is about 7.83:1. The 17/44 Primary set reduces that to something around 6.6. I did the math from the gear table found Here.

You might be better off finding a slightly taller set of secondaries - if they exist for our scooters - or primaries. This assumes you didn't discard the stock gears when the secondaries went on. Even Mighty Malossi has its limits. Just suggesting.