Who Needs Synthetic Oil?

[F6Dave]

This board is so quiet that I worry our sponsors will pull the plug. So I'll post results of my recent oil analysis which should interest some.

I've read that motor oil has become so standardized that brand and even type makes little difference. So I decided to switch from Mobil 1 synthetic to Rotella T-4 conventional in my '99 Valkyrie Interstate, which has a very similar engine to our F6Bs. I had the used oil analyzed for both oils to get a good comparison.

The conventional Rotella worked just fine. Wear metals were lower but that may be due to a shorter change interval. In fact they're better than the averages for GL1500 engines. The only downside was a loss of viscosity. It wasn't enough to be a real concern but I might not try running it for 8,000 miles. Have a look at the results. It's interesting that Rotella uses less moly and a different mix of anti-wear additives.

BTW I'm using those cheap Super Tech filters from Walmart.

[SpencerPJ]

I use to run Rotella dino oil in my previous bike. I tried the syn version of Rotella in my F6B did not shift smooth with it. I'm probably the outcast, I run basic Honda Gn4 oil and filter, delivered from Amazon, change at 5k, runs and shifts great imo.

[JackB]

I’ve been using Rotella for 25 years in the 1500 Valkyire up to the 1800 Valkyire and F6B no problems.

[jm21ddd15]

Plenty of good oils on the market. Some oil filters, well questionable. Personally, I run Synthethic oil, mainly because I like the viscosity in my home state of Wisconsin. I ride in cold temps, and no need to warm up the engine oil. And it does get hot here too. anyway, oil choice is a personal choice. Back to your tests on your oils, I wondered how many miles were on your air filters? Were they equal? And were they both stock air filters? This can make a difference too. Some of the "free flow" type air filters are not so good, especially if not maintained as required, such as washing them out and re oiling them at the proper intervals. Not criticizing just wondering out loud.

[F6Dave]

The air filter has run less than 20K miles so it shouldn't affect anything. But it is interesting to note that silicon was nearly 3X higher when I ran Mobil 1 than the recent run using Rotella. There's a stretch of road near my house that was unpaved until recently, so the reduced dust may have contributed to the drop in silicon. I should add that while these tests were on my '99 Valkyrie, my F6B uses an air filter of similar design and size.

I always run Honda OEM air filters. Years ago I used a K&N on a KZ-900, and an OEM wash and oil filter on a different bike. The cleaning/oiling process is a pain so I have no interest in using one again. But there are other reasons to avoid them. They let more dirt into your engine and clog up quicker. It's easy to see how the dirt gets through as they're visibly more porous. I suspect the shorter service interval is because they have fewer pleats and therefore less surface area. But that's a topic for another day!

[jm21ddd15]

I agree with your comments about the K and N oil filters. I had one on a Kawasaki, and they are a pain to maintain properly. Because they are a pain, it probably means people delay doing the proper cleaning at the scheduled times.And I also agree they let in more dirt.
I use Honda oil and air filters on my F6, and have no issues. Yes, people can save a couple bucks by buying aftermarket filters, but that is their choice.