Fe 570 rebuild

I can tell you about my 2002 650 for comparison. I did the crank bearing upgrade and DVS kit at 70 hrs and then put over 500 hrs on the bike with similar riding to you. Occasional high speed stuff but mostly calm riding. Regular oil changes and valve checks. When I sold the bike the engine was as healthy as it was 500 hrs earlier. The ONLY problem I ever had was a leaky water pump, twice.

I wonder why the original owner had a top end job done at 105 hrs? That is way too early to do under normal circumstances!!

if it helps, i have 5x 450, 2x 390 and 1x 570. all the 70º model. It obvious depends on the kind of riding and riding style but in general they are tremendous strong. overhauled one bike some time ago where the big-end bearing failed. the bigend pin surface had been worn down aprox. 0.5 mm (1 mm play) but the bike was used to the last minute.
Same goes for the timing chain, it might be in a very bad shape but it will not break. In the past I had many big fails with the old models: broke big end pin, broken timing chains. I learned the hard way.

made a very stupid mistake not so long ago and lost more than one liter of engine oil. By sheer luck (pinched tire) I noticed it. The bike is still running lovely...

If I had to namy any weakpoint it is the valve drive train, the rockerarm and roller. They tend to wear (end of the oi traject, under cirumstances poor lubrication).

cheers,
Adrian

PS most of the bikes had done more than 40.000km/ 1000 hr