Get one while you can. The Dolmar/Makita 401s have been discontinued in favor of the new, heavier 420.
I bought another 401 used, and reputed to be scored. Finally I had an excuse to pull the top end and see what they look like inside. True, the conrod is flat with uncaged rollers, but rather sturdy looking, more so than a Stihl 024. The piston is 40mm, single 1.5mm thick ring. Transfers are open into the crankcase.
The saw had 120# compression cold, but the ring was stuck, and I couldn't free it without breaking it.
The cylinder has a just a thin vertical line of aluminum transfer, so will clean up beautifully.
I checked squish, and it would have been .037" with the .015" fiber base gasket. I will delete the gasket, and this should boost compression by 20# in that size bore.
Recommended max rpm is listed at 12K. The stock muffler is restrictive. With a minimal mod to the muffler outlet and retune, my "runner" was turning just shy of 13K. With another mod to the internal baffle It turned 14.2K+, but seems strongest 13.6K-13.8K tested "in the wood". This was muffler modded and carb tuning only, so no porting or removal of the base gasket was required.
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Not sure if I will mod it but I did buy it!!