You can switch over to Michelin's, I am running my Alto on it and it is just 250km old, absolutely no noise and great handling...
As far as the correct upsize, I suggest some experts (like Samurai, rks) can provide u with details on it...
Since u r changing tyres I suggest u upsize and change to Alloys... Alloys with Tubeless works the bet....still, in steel rims tubeless tyres will be fine too....
PM Samurai, he can help u with the correct upsize for Santro Xing...
Abhi
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2003 Bajaj Caliber115 | 2006 Alto LXi
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