A bottom end rebuild is not as difficult as it seems. Yes take your time, do a lot of reading, and video review. If you think about it, its a mechanical machine, it's just nuts and bolts. Follow the manual and you will be fine. I have my son's KTM 250F which I've split the cases and removed the crank I'm waiting on the parts to arrive so we begin the rebuild. Yes there are a few specialty tools needed like a flywheel puller. I took the engine to a local shop and they pulled the flywheel for $5.00 I was able to split the cases without a case splitter.
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