Find the certification of the oil, and then find an oil that still meets that cert. If I recall from the last time I was in a 650 final drive there aren't any brass bits, so you should be okay.
As for synthetic, semi-synthetic, or conventional, either do fully synthetic or fully conventional. No real benefit to going halfway. If you do a lot of high speed riding I'd go fully synthetic, it handles heat better. Kurt On Aug 25, 2015 10:37 AM, <[email protected]> wrote: > Just had a quick question about changing the oil in my final drive. The > original recommendation is for 90w oil, for use over 40 degrees F. Since I > virtually never ride below that temperature, I figure that's the one to go > with. Is that still the case? It seems finding straight 90w is a bit > difficult - my local dealer only has 80-90w. And should I use partially, > or fully synthetic? I've got 21k on the bike, and the owner's manual says > change it ever 24k, but the Clymer says every two years, so I'm sort of > splitting the difference because I've never changed it and it's been 20 > years. Thanks for any replies. > > -- > You received this message because you are subscribed to the Google Groups > "Nighthawk Motorcycle Lovers!" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/nighthawk_lovers. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/nighthawk_lovers. For more options, visit https://groups.google.com/d/optout.
