Valve Clearance help

Hello again

Getting to know my 1999 610E SM by taking things apart and back together!
Have got starting issues and although she will start in the end, it is a long and painful process!
Will do a check list (spark plug, compression etc) but also want to check valve clearances.
Can't I just check the valves by taking off fuel tank or do I need to dismantle the cooling system as well?
Also I read somewhere that you need to drain the oil, surely this is not necessary???
I am sure there is a guide of how to somewhere on here (found the you tube vid for other bike), could someone point me in the right direction please?
Thanks
Chris

Check your pilot jet first, easiest. It should have a perfect concentric circle when held up too light, no fuzzy.

I am not sure on the older models, but on the newer, it's unplug the hoses and bend things out of the way. You can hold things with a bungee cord or zipped zip tyes.