Indeed I had been doing my research too. The tyre vendors were pushing me hard towards 185/65-R15 but I insisted on 185/65-R15. Had this been a 1.3L Vitz, I would have went with 195/55-R15 hands down but in this case I don't want to put unnecessary burden on the engine. Also as @VCheng very validly said that unsprung weight has to be catered for which Alhamdolillah I did when I bought the light weight alloys with acceptable offset. That's how you can check the unsprung mass else with that engine displacement and type of suspension, you're inviting trouble that will show up anytime after 8-10 months down the road. Nevertheless, if someone could convince me on 195/55-R15, I'd be happy to put in some narrow sidewalls with those nice set of Lenso Project D Spec F.
I've tried and tested these tyres. To be perfectly honest with you its a tyre that Yokohama aimed at placing between the various series of A Drive and Advan. And trust me, the C Drive proved to be a jackpot for them. Its an all-round performer and is very consistent with what Yokohama claims (provided you get the genuinely fresh stuff). And yes, such things in life do cost an arm and a leg. Presently, the I've bought these Kumho TA31 tyres (manufactured 2015) on the insistence of a friend who has claimed that they will satisfy my driving requirements or my money back (with Rs.1500/- depreciation). But in return I have to write down a professional review for them. He clearly knows what I've been using in the past and my experience with Michelin, Continental, Dunlop, Pirelli and Bridgestone (Ultra High Performance or Performance tyres from every brand mentioned). So lets see.
Other options were the Nankang NS-2, Yokohama Blue Earth, Jinyu in 195-55-R15 but like I said earlier, I'm not sure with this profile. Anybody who has been through this rut? Would greatly appreciate if he could share his experiences in that profile. I surely wont like to compromise and settle with a slightly heavier EPS and the ABS kicking in earlier than usual apart from a wrecked suspension in the future.
Car manufacturers always keep wheel plus sizing as future possibility, may it be the company itself or the customer. The suspension is tested on various sizes and car handling/response, other performance and fuel efficiency. Having said that, its not just the overall diameter or going up from 14" to 15" to 16" (+1, +2, +3) . The weight, correct offset and width are of paramount importance too. In my case I knew 6.5" wide rims would be hard to come by specially in the choice that I made. So, discussed with the vendor at length and did some googling. Went ahead happily with 7" and trust me I don't regret it all since the profile is nice and balanced. Stretching becomes a problem when you go beyond the specified/allowed widths.
I had almost struck a deal for a set of great condition Suzuki Swift rims but they weighed more than these Lenso PD-F and looked less striking.