That is some great work, that thing is going to be a tiny monster when it's done.
Originally Posted by Donkey Hotey
The LC4 is known to be a paint shaker. I'd seriously rethink the design of that front mounting system.
x2, no big deal though, IMHO all those tabs need is a rib welded down one side to stop side-side flex. For a few grams of steel you'd gain a lot of strength.
On the oil system, if you are using the standard circuit, be aware that the big end bearing will be getting no oil while your tank fills up. That's why it's standard practice on the 640 to fill the frame separately & bleed out the air so the crank gets oil asap.
That cam bearing failure is a bastard, haven't seen that before. I've always replaced that bearing & the other end one on mine when doing the cam followers (which are known to wear out) cos they're cheap but they've never been worn. Good luck with getting that sorted & I look forward to further updates.