Modern Vespa

I have a vespa LX50 and it runs really well but I'd like some more power.

I'm happy with it so I don't want to upgrade to a 125

Over the next few weeks I'm going to do some work on it

I'm going to put these malossi air filter sponges in

https://www.sip-scootershop.com/en/product/air-filter-sponge-malossi-red-sponge_M1411778

https://www.sip-scootershop.com/en/product/air-filter-sponge-malossi-double-red-sponge_M1414532

My question is do I need to upjet my carb or can I just put them in.

Thanks

If your bike starts to go really fast, then stops running completely and there's a hole in the piston, you probably should have up-jetted.
Despite what some people claim, if the jetting is correct, you shouldn't have to change the jetting for an exhaust or replacement air filter that's going in the stock box. That's because the inlet for the stock box doesn't change. On many stock two strokes sold in the US during the last few years when you could get one, the jetting was so lean that if you did nothing, the scooter would burn up. After the EPA realized all the importers of Chinese two strokes were using photocopies of the exact same lab results (who could have seen that coming?), they put the guy in jail who was certifying all those scooters and made the importers re-test each individual model. One of the tests involves putting either 4000 or 6000 miles (I don't remember which) on the engine and having it still meet emissions standards. Once they were jetted correctly to meet the last US emissions standards for 2 strokes, the Chinese two strokes tended to melt down long before reaching the end of the test. That's when companies like Keeway, CPI and Binelli all vanished from the US Market. When Genuine Scooter started selling LML models, they were jetted so lean that many of them burned up before the warranty period ended. The quick and easy fix was to look up how a stock 1978 PX150 was jetted, and switch to that.
So by jetted correctly, I mean jetted with the best air fuel ratio for the motor to run correctly, not to run as lean as possible. If your scooter is jetted correctly, a new air filter in the stock filter box won't require rejetting.

Hard to believe that all those 3D fuel maps using two lambda probes with several other sensors like air temp, air pressure, airflow, etc, etc... could be easily replaced by a carb with same results regarding the best mixture. Especially while those carbs even need to be rejetted if the temp is low or elevation changed or whatever else.

Perhaps not "same results" but certainly there were and still are many carbed vehicles that run really, really well and without the added complexity and concomitant expense of vast electronics and computer control.
Like a lot of simple mechanical devices (e.g. fountain pen, watch) when it works well it's a versatile, economical pleasure and a joy to use.

The problem is that "working well" and "fits to ecological standards" are not the same. For working well the mixture should be a bit rich.

Ok guys so what should I do?

Use this one and not touch the carb
https://www.sip-scootershop.com/en/product/air-filter-sponge-malossi-red-sponge_M1411778

Or use this double one and not touch the carb
https://www.sip-scootershop.com/en/product/air-filter-sponge-malossi-double-red-sponge_M1414497

Thanks

Well, that's just uh, like your opinion, man. The way I see it is that our overlords, while preaching about simplicity, sustainability, reducing, and reusing, constantly move the goal posts to reward their co-conspirators to force us to live in an ever more technologically complex world. An engine never needs to run "slightly rich" or "very lean." It should run where it runs best.

Well, most offroad bikers know that a richish mixture makes the engine run better than a leanish one. Ask them.

Sorry guys I'm new to all of this, what should I do. I don't want to mess with the carb until I get more experienced in the summer

This
https://www.sip-scootershop.com/en/product/air-filter-sponge-malossi-red-sponge_M1411778

Or this
https://www.sip-scootershop.com/en/product/air-filter-sponge-malossi-double-red-sponge_M1414497

How would I know if it runs rich or lean?

Thanks

If only there was a site where you can put this sort of question into a search box and google a list of results and videos that would answer your questions about scooter tuning, air filters, rich vs lean running, and everything else you want to know about tuning your scooter.

I understand how you read it with the spark plug, just wondering if anyone has any knowledge specific to the lx50 2t