Looking to buy a injected 4 stroke need advice

[kirah65]

Right as the title says, I'm currently on the lookout for a fuel injected 4stroke, however I only have experience with pre 2000s 2stoke scoots.

I know 2 strokes are generally faster and all that, but I'm just done dealing with carburetors and all their tomfoolery.

Anyway, so what I have available locally (brand new) is either the Kymco Super 8R 50i, Kymco Agility City 16+ 50i, PGO/MOTOCR R9 SP 4T EFI EURO 5 or the Piaggio Zip 50 S Euro 5.

I also like really like the Honda Ruckus / Zoomer, and it has a direct injection version, but I have not found any Swedish retailers that sell it.
I have only been able to find them used and only one of them is the fuel injected model from 09 so if anyone know of any places in Sweden that sells the Zoomer / Ruckus / NPS50 feel free to let me know about it.

(I wish bikes were named the same worldwide, makes shopping for stuff confusing like how the Zuma is sold as the BWs50 or the Ruckus as zoomer / NPS50 just why)

Also, generally, how difficult are these types of bikes to tune? I know It's not as easy as a 2-stroke bike, but as they come a tad too slow from factory (45km/h/28mp/h) to keep up with traffic on some roads around here where bike paths are not available, how difficult would a relatively minor(?) tune be?

Keep in mind, I'm a large dude, at currently 110 kilos/240punds. (I'm working on it) Reason I say minor tune as most 2 strokes simply getting an unrestricted drive boss and pulling the plug out of the exhaust is generally enough to get a significant bump in speed.

I have heard that exhaust replacements / mods don't do much on 4 strokes but what about the variator drive boss?
Although any cheap / easy ways to get some more speed out of these, would be greatly appreciated I only need a like a 10-15km/h/5-10mph bump which is really easy and cheap on a 2stroke, but I have no idea if it's the same on a 4stroke

Any advice, tips, and recommendations are greatly appreciated.

[GrumpyUnk]

In case you have not gotten the clue, most on site don't fiddle with injected machines in attempts to increase their performance. So I volunteer to let you know what I think is the expected response.
Anyway, I do not see how you can increase performance other than simple things like a variator block that limits motion, or a rpm sensor that cuts ignition/fuel/? at some limited rpm.
The injectors are set to deliver a specific amount of fuel that may be diddled with adjustments indicated by an O2 sensor in the exhaust stream.
If you could replace the piston/cylinder with a larger size, the injector may/may not add sufficient fuel based on how it determines fuel flow. If it measures airflow, it knows gm/second of air... and adds roughly the correct amount of fuel to match. If it measures manifold pressure(MAP system) it knows ballpark fuel for the given manifold vacuum and throttle position. Air volume changes on a MAP system are more difficult as the table of injector pulse width & rpm & manifold & TPS & ambient air & ??? are fixed, without knowledge of the amount of air ingested. It assumes the amount based on the volume of the factory cylinder/piston. A MAF is more able to compensate for increased engine displacement, as it measures the airflow RIGHT NOW, and adds fuel it thinks appropriate... Dunno if it considers rpm, but likely considers ambient, tps, etc.
tom

[aeroxbud]

I know a few companies here offer big bore kits for the newer Euro 5 Chinese fuel injected scooters. They require switching from injection to a carb as part of the kit.
It means always having a warning light on the dash.
Vespa scooters are offered kits by Malossi which has a new ECU for the injection. Not cheap.