My wifes GD did almost 90K and mine did over 110K and never had tappets looked at, I suspect recommending tappet adjustment every 25K at over 300 notes a pop was a work creation scheme to keep Honda workshops busy in the absence of regular work from cambelt changes (Honda cars are so reliable that it must be hard to keep their staff busy).
You can read posts on forum from way back about people checking bolts that would need to be removed to do tappets and seeing that dirt on bolt head had not been disturbed by application of any spanner by Honda. IMHO they just leave the car in the workshop all day, clean it and give it back to you with a bill for lots of money.
If tappets went very quiet because gap had closed (rather than noisy because gap too big) the result would be a burnt out valve and massive drop in performance.
Unfortunately you cannot check if Honda did anything for the money you paid them, as no visible signs of whether work was carried out - and even more telling is that I have never seen a post on this forum of anyone having an engine fail due to not having tappets adjusted - Honda say vehicle may fail MOT emissions check if tappets not done, can anyone tell us if their GD failed MOT in this way, and if tappet adjustment made emissions good enough to pass ?
