go-kid wrote:was told air filter and plugs were changed and got charged for them.
I'd be straight back round there and ask them to show you one of the filters they sell, as well as the plugs (part numbers on the invoice?) Get them to compare them with what's on the bike, naturally in your presence.
That info on the counter and visually checked, I'd then ask the service manager to (quote) "start explaining himself prior to you asking for advice from the Thousands of members of Visordown, MCN, RiderSite and the Bandit Owner's Club"
That will usually help the said manager to understand the position he is in.
Worked wonders at Kwikfit for me some years ago when I suffered something similar
Seems a bit harsh. 
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