Im 6 feet tall guy planning to buy r15 v2 .I heard it causes backpain in tall guys like me is it true??

Yes that is true, better go for Bullet 350/500

Rubbish. Learn to sit correctly on the bike and you will never have back pain. The R15 is designed to be used on the track and therefore it's riding posture will never be as comfortable as streetbikes like the Unicorn, Pulsar, Bullet etc. But it's not so bad. take a test ride and see how well the riding posture suits you before you buy it.

Trust me that it totally depends on your riding posture and also how far you are going to ride. If you are planning to use this bike for long rides better take a test ride before you buy it and if you have already purchased than you need to learn the correct riding posture as suggested by Sam Dinkar.

I own it and backache problem is bulls@@t.