I am surprised and disappointed at the hostile responses.
Deepak is not evading tax, he is minimizing his tax payments. You seem to be unaware that Indians have the pleasure of paying a customs duty ranging from 40% to 50% of cost of (bike + shipping).
Deepak: As suggested, file a dispute with the payment processor and contact the German Embassy in India for alternatives. Leaving a negative feedback at
Trusted Shops | seal of approval, seller rating and buyer protection for online shops may help.
Germany also has effective consumer forums and filing a dispute should help. Google.
Btw, tourists are out of luck with respect to sales tax. No refund.