Chainsaws

Trying to drill small after tip has been assemble is asking for nothing but trouble as you can damage the pancake roller bearings and introduce metal shavings can also damage the bearings.

On a side note before I started repairing chainsaws I used for nearly 30 years and worn out plenty chains and a few bars. I never greased a tip. Since I have been working on these I have only seen two bars with bearing failure and was because the bars were completely worn out and chain had slip pass the sprocket on the tip separating the bar tip.

The best thing to do is make the chain is oiling properly, the bar groove is keep clean and that you use a good oil, none of these used motor oil tricks.