I checked mine myself at 6k because I thought it was noisier than it should be - both set of valves were too loose, the exhaust side slightly worse. Motor was much quieter as a result, not silent, but a noticeable difference.

Checked them again at 12k. Both sets spot on (exactly as I set them at 6k). Also checked at 24K and 36K. No need for adjustment, still unmoved!

As has been mentioned above, unless your bike has a noisy, rattly and tappety top end or, is suspiciously too quiet, then leave the valves alone until at least the 12K recommended interval.

Remember, too quiet is potentially more destructive than too loose.

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