I think if they were to change laws it would have to be to anything forward of that date.

Same with everything else. Old cars don't require seat belts or fog lights or airbags if they weren't fitted before hand. And would be in the same way that ABS on bikes from 2016 won't affect bikes that are released now.

Also allowing the bike to breath more and adjusting the fueling shouldn't increase the emissions. If it's done properly you should get a more complete burn.

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Yamaha XT660X '08' Blue | DNA Stage 1 | MTC 2 into 1 Carbon Oval | OTR Tail Tidy | Engine Painted Black |