Just to address to one-way bearing issue mention at the very beginning of this page and the tail end of the last page......

As many of us know the one-way bearing will slip from time to time, and will periodically need to be cleaned. Everyone will have their own opinion on how to do so, but the best way I've found is to pull it from the back of the engine, soak it in denatured alcohol and then blow it dry with compressed air. OR, there is a quicker way which has worked flawlessly for me each and every time I've done it, which can save you from needing to pull the engine and disassemble the backplate each time the one-way starts slipping. Pull the glow plug, and put a one to two second shot of WD-40 down the glow plug hole. Then tilt the engine/vehicle to allow the WD-40 to run down towards the backplate and one-way bearing. Let it soak for about 10-15 seconds and then try the starter/pull start, etc. It may take a few spins or pulls for it to catch but once it does it'll be good to go for a while.

Drilling holes in the "starter" backplate sounds like a good idea but if you do any off-road running at all or in any type of dirty environment, unless those holes are plugged you'll be getting dirt in there which can work it's way into the engine possibly. That can spell bad news if enough dirt gets in there.

Anyway......that's just my two cents........take it or leave it.......