Chainsaws

Mark, I am kind of curious about your bar problem. I have two Husqvarna 455 chainsaws and three bars, one 24 inch and two 20 inch, and have No wear or replacement issues.  I just finished cutting up five black oak 2 ft in diameter 70 ft trees with no problem, and at my current wear rate, they will out last my use. Oregonchain.com has a site that will help you select the correct bar, chain, and sprocket, and a good crossreference at your favorite chainsaw chain and bar supplier will easily crossreference you to any bar manufacturer that you would like. Also, I have never heard of drilling a tension hole in a bar unless you are trying to fit a bar that does not fit your saw, which i definitely would not recommend. Remember the drive sprocket, chain, and bar must work together, and be matched to work together, Again "Oregon" does a great job of doing this match for you. Some individuals don't take much time doing bar maintenance, they sharpen the chain and then put it back on the bar with No further Maintenance. Here are some suggestions that I do everytime, I sharpen my chain or replace a chain.

Step 1: Inspect the Bar, chain, and sprocket everytime, it takes about 2 minutes, On the bar your looking to see If the bar has any burrs or sharp rollover on the guide edges, If it does take a flat file and at a slight chamfer angle file the bar on all four edges. In-addition, set the bar on a real flat smooth surface, and make sure the bar will stand straight on both edges, kind of like standing a quarter up on edge.  Also any damage to the bar, like a bend or crack near the lube holes, and If you use a sprocket nose that it turns freely. The chain sharpen and inspect links for wear and damage, and finally the Sprocket to see If it is worn, I might also add lubricating the sprocket bearing, or occassionally removing and replacing, they are way cheaper than a sprocket or bar.

Step 2: Thoroughly clean the Bar, chain, sprocket, and clutch cover housing, I use compressed air to blow out all the saw dust, then I wash the bar and chain down with Water and Amonia cleaner (1 cup ammonia to 1 Gal. Water ), soaking the chain first, It works great and in about 5 minutes its sparkling clean, I also use a stiff bristle brush like a small tooth brush for stubborn pitch, but it all comes off. Cleaning the bar, I use a groove cleaner and make sure there is no lumps of grease, sawdust or anything in the grooves. After cleaned I again blow off any moisture with compressed air, followed by spraying down the chain and bar with WD40 lubricant.

Step 3: I would definitely recommend the "Power Mate Sprocket system", The initial cost is replacing the clutch drum, but there on after you just replace the rim and not the entire sprocket, when the drive sprocket starts to wear. Also just the rims are reasonable, compared to an entire Drum Sprocket  spur replacement.

Step 4: And finally when I put everything back together, I put lots of barchain oil on everything, run the saw too, and make sure the oiler is putting plenty of oil on your chain, If your using a 20 inch bar and have an adjustable oiler, then crank the oiler all the way up for max oiling. The difference of saving a few ounces of barchain oil is Not worth the price of a bar either.

Its a little wordy but I hope this helps, and it really only takes a few minutes, to Maintain your Bar, Chain, and Sprocket. Oh, If you don't do your own saw maintenance then take it to your Authorized repair center, and periodically tell them this is what you want done. I could also probably write the chapter of a book on maintaining Bar, chain, and Sprocket but I believe these tips will help save your bar from continuous replacement.

PS. Here is a picture of a Homelite Super 2 (1978 model) saw that I recently cleaned, So Your saw should look like this or better. Oh, Its the Original Bar too!