ONE MORE TIME - RE-FORMULATION: The EPA specs have changed recently and the mileage for cager's Catalytic Converters has been doubled and some oil manufactureres have changed their specs circa 2000. Here is a comprehensive short article on the subject.
April 25, 2001
"Oil, oil, toil and trouble"
You can just about see the old witch stirring her caldron as she brews up the latest batch of brew. Only in this case, it's motor oil.
Never has there been a more controversial subject when it comes to infernal combustion engines! It could be your car, your lawn mower, or in this case, your motorcycle. So what's the big deal?
Well, the first problem is they keep reformulating motor oil for one reason or another. This would be fine except most of it is aimed at car engines and most motorcycles got a couple of other considerations. This would be the shared transmission and wet clutch.
So, as the oil companies have reformulated car oil to keep it from contaminating the catalytic converters, they've cut way down on historic extreme pressure/wear additives such as zinc. They've also gone to thinner viscosities in an effort to increase gas mileage through decrease pumping losses. Hence, the new 0W-30 oils and what not. As a result, some people have observed increase wear in the transmissions, especially the gear's tooth surfaces.
Next, in an effort to gain back some of the extreme wear protection, some oil producers have started adding other additives such as Molybdenum Disulfide, commonly referred to as just plain Moly. (Frankly, I had to look up the spelling myself for this article!) The stuff is really great for some applications such as an initial surface for new piston rings and for making motor oil more slippery. It may have some consequences for motorcycle wet clutches, especially in higher powered bikes.
Now, let's revisit good old Honda, maker of our beloved Valkyries and assorted other gasoline engine devices. Honda is huge and high tech when it comes to gasoline engines, right? And they offer their own line of chemicals including motorcycle motor oil, so they must be right on top of things, right? I mean if Honda isn't, who is? This is where it gets scary boys and girls.
For some time, Honda has offered two basic motor oils for bikes, GN4, a conventional dino oil and HP4, a dino/synthetic blend. Honda doesn't actually produce the oil but has it made to their specifications by regular oil companies. This is a common practice through out the industry by the way.
In recent years, Honda has established guidelines for their motorcycles whereby they recommend either GN4 or GN4/HP4. The latter designates you can use standard GN4 or the synthetic blend, HP4. If your bike is designated as GN4 only, Honda does not recommend HP4 be used in it. This would imply that other synthetics/synthetic blends might not be appropriate either. One of my motorcycles, a '94 Honda CB1000F falls into this category. And we've found this particular bike to have a somewhat weak clutch in that it won't take a lot of abuse. My VTR1000F was rated for GN4/HP4 and so is the Valkyrie. Both are considered high torque engines so we could also assume that Honda feels the clutches on them are up to use of HP4.
Now we'll drop the bombshell Honda has just announced a reformulated HP4 for use in the new 1800 Gold Wing.
It has no Moly additive.
I don't know what other changes it has over the older HP4 with Moly, which is still listed. I also know the 1800 GW has more torque than the 1500 GW and Valkyrie engines while sharing the same basic clutch. We'll get more information as it's released.
What does all this mean? Too soon to tell really. My experience has been that if you have a basically stock Valkyrie, you should be able to get by just fine with any good motorcycle rated motor oil, dino or synthetic, as well as a lot of others. There's a ton of reports out there on this subject, but be warned again, they are constantly reformulating the stuff. So, what's hot this week may be less than optimal the next.
If you have bolted a blower on the old dear or like to drag race a lot and do burnouts at every other intersection, you may also experience clutch problems on your Valkyrie that are exacerbated by the type of motor oil and any oil additives you use.
Now, I know I can't leave without a recommendation or some of you will hound me for weeks. I've only got one, it's entirely personal preference, and it works for me, OK. As always your own mileage may (and most likely WILL) vary.
I use Honda GN4 in all my bikes. I buy it by the case so that it's cheaper and I try to change it, along with the filter, every 3,000 or so miles. I know this is a conservative approach, but it has never let me down. In the past I've used other stuff including HP4 and full synthetics with varying degrees of success. I also don't abuse the clutch as a rule but have been known to light the tire up occasionally. Hey, I'm only human!
Now, I also know this post is going to start a ton of differing opinions and anecdotal experiences that will run the entire spectrum. So be it, cause like I said at the beginning, there ain't nothing more controversial than a man's (or woman's) choice of motor oil. You at least have the latest news as I know it.