Yamaha R15 BS6 vs BS4 – let us list the changes in pictures and see which one looks better now.
Yamaha launched the new R15 with Bharat Stage VI compliance (launch story here) in December 2019. Here is a quick pictorial look at the old vs new colours.
Yamaha R15 BS6 vs BS4 Colour Changes
Racing Blue – Rs 1,45,900
The Racing blue colour has the maximum changes. In pics, it appears to be slightly lighter in shade; contrasted with silver coloured graphics on the fairing in place of black and comes with blue coloured alloy wheels (instead of black of the older version).

Thunder Grey – Rs 1,45,300
Thunder grey is now greyer than before. The top part of the fairing is now black coloured in place of red and this is replicated on the top of the tank as well. There are contrast red ascents on the grey coloured fairing.

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Darknight – Rs 1,47,300
Darknight appears to have received the transition almost unchanged.

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Apart from the new colours, the R15 BS6 also comes with features like side stand engine cut-off, dual horn etc.