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One of the baffles in the exhaust is collapsing and the dealer said this is cause, sounds a bit dodgy to me. Any one any ideas. TBA is 4 year old and has not that many miles on.



Good word, yeah that all sounds strange to me. They did all that work to the top end of a motor with low miles? Did they check the coil pickup gap? My bike exhibited symptoms like yours. I pulled the cover, check the gap and found it in the new factory spec (it's wrong in the manual, well updated). I put it back together and it hasn't had an issue since.
Last year, my kickstand spring was weak, causing it to bounce down over big whoops, bridges, etc which turned the bike off. A new spring solved that one.

Al