I can almost guarantee...
Every time you see a motocross, enduro, trail, or other off-road bike advertised for sale, it comes with those blanket statements. And what I've discovered over the years goes pretty much like this:
- It might not have been raced against other bikes, but it will have been thrashed mercilessly from day one by someone with no understanding of mechanical sympathy whatsoever.
- The "rebuilt engine" may indeed be completely accurate. It will have been stripped and inspected, parts priced up and found to be too expensive, engine subsequently rebuilt, with the old parts, and bike offered for sale as soon as an ad can be written. Now, if you're very lucky, but don't hold your breath, the "rebuilt engine" may come fitted with brand new gaskets. Ooh!
- The age of the bike, and monetary value to the owner, is uber important. It's the difference between regular oil changes and a clean, oiled air filter, and a black sludge, full of metallic particles, semi-circulating around the engine, with broken bits of dirty foam floating around the air box where an air filter used to live.
It is that simple, and brings me neatly into todays little job. The bike, an XR80A, isn't actually for sale; it was given to a mate to use but, before he does, wanted to get it looking good, and running properly. So, he says to me, "I'll clean and paint the rest, but the engine just needs a new head gasket, it's leaking oil".
Yep, all that's wrong with it - so, whip the head off, replace the head gasket, check the bore while it's apart, just in case we want new rings etc. and slap it back together. It's a walk in the park!