Re: Oil Change - the Good part and the Bad part
 

I use 20W50, mainly because the previous owner was. That and, as you mentioned, the heat down here. Mine's pretty much a daily driver, only about 20 miles or so a day, from Beachside over to FIT and back, plus running out for lunch, all in what passes for traffic in Melbourne.

As for Semi vs Full Syn? I dunno, full synthetic is probably better, especially if you go past the recommended intervals for oil changes, I do mine at 1500 miles, and, as the manual calls for, change the filter every other oil change.

The Castrol Actevo really looked better at 1500 miles than the Castrol (Not sure which blend) the previous owner used when I changed it right after buying the bike. It was still pretty golden colored, the stuff she used (about 2000 miles, according to her) was pretty dark. Really, though the semi syn gives me a nicer shifting feel, and seems robust enough to handle the wear and tear.

Re: Oil Change - the Good part and the Bad part
 

Here's the web address for that article on oil from Calsci.com if you want to read it: http://motorcycleinfo.calsci.com/Oils1.html very informative from a guy with no money stakes in the oil industry as far as I can tell. He's certainly not going to make a ton of money just by getting bikers to change their oil choices even if he only recommended one oil, which he doesn't and we all changed to it, which we won't, so I thought it was pretty unbiased in that aspect.

By the way, a few years ago I did some work for a company that tested motor oils and lubricants, mostly for cars not bikes, and it was very interesting to see how much better most of the name brands did than stuff that you got off the shelf at the 7-11 in a generic container. It was also interesting to see how much better all the synthetics I saw tested outperformed every conventional oil and not all synthetics tested the same, although all of the synthetics that I saw still outperformed conventional in things like film strength and thermal breakdown. I also observed that additives added to almost any motor oil changed the performance characteristics for that oil (not always for the better) and outside of the difference in base oils (syn vs conventional) that made the most difference in performance. Some of the no name brands were really poor in film strength and thermal breakdown and I mean REALLY poor, so please don't put those in anything you care about lasting. Now having said that, this was over 15 years ago and motor oils have changed immensely in that period of time but the main thing I took away from the experience was that not all motor oils perform the same and the synthetics always outperformed conventional under stress and duress.

Re: Oil Change - the Good part and the Bad part
 

For anyone interested, I went and bought a gallon of Rotella-T synthetic today for my Kat. Last time I went to Walmart, a gallon of the stuff was $23 (IIRC). Today it was $19. I was happy. :)