As some of you know, I had major work done on the bike. I'm wondering at what point (if ever) should I switch to synthetic oil? I have put 3500 mi. on Honda GN4 oil with one change at 1000 mi. Should I make a switch? If so, what are the pro's and con's? How many miles after break in, is it normal to make that switch?

 

From what I have heard, running regular oils, or blends are better then full synthetics as long as they are changed more frequently. The pros for synthetics are more consistent viscosities over a broader temp range, so thinner when cold (better for cold starts). Less molecule breakdown over longer periods of time, still gets dirty just as quick as regular oil though. And that's about it. It's more money, as for engine wear, i've heard that petro based oils do provide a better lube when new (something to do with inconsistent molecule size) . However, they do break down faster.

I think it's really personal preference. If you change your oil a lot anyway, i would run regular, or semi. Don't waste your money.. However, if you are one of those lazy maintainers and do your minimum, run synthetic.

 

Since synthetics first came out in the 1970's, I've never seen a reason to spend the extra cash. I've had engines go over 330,000 miles and still run great with petroleum oil. My '98 4Runner has 265,000 miles and is still at the full mark on the dipstick when I change it every 3,000 miles, using 10W30 Castrol GTX.

As far as viscosity goes, any oil rated at 10W40 has to meet the low temp flow requirements for 10W (W = winter) as well as the high temp "summer" requirements of 40 viscosity. The oil is tested for how long it takes a certain volume of oil to flow through a certain size orifice at a certain temp. All oils have to pass this test according to their viscosity rating.

I use Honda GN4.

 

I'm not sure if you put new rings in. Seating the rings is the main reason for not running synthetic at break-in. I don't know for sure, but I think you want to run ~5k miles before running full syn, with new rings.

I run HP 4 in my bikes and full synthetic in my truck. I run synthetic, because I believe it has better film strength and gives better startup protection, which is when the majority of engine wear occurs, especiall in cold weather. I know dyno oil is almost as good, but I just do it anyway. I change it myself and spend the money on oil. Doesn't make me any smarter, though.

Synthetic oil is not a valid reason to run longer between oil changes. Combustion products collect in the oil, including abrasive carbon particles and corrosive chemicals. The filter ony removes the big particles. When the oil turns brown, you need to change it.

 

I only recently switched to synthetic on my bikes. I've run dino for the past 25 years, and even automotive oil. I don't go longer than a 2500 mile interval between changes. In one of my bikes, I'd noticed a good bit of top end clatter with dino, but noticably quieter with synthetic. I'm at the change interval with that bike, and the engine is still much quieter.

Having said that, I believe that being consistant with oil changes is far more important that what type of oil you are running.

As for your mileage, you should be fine to switch to synth by 3500. I know a number of guys who bought new bikes and switched as soon as the breakin interval was met. You're well beyond that. JMHO...

 

I run rotella and have used both the synthetic and the regular. I generally change when i notice shift feel degrading - usually at a little over 2000 miles regardless of which I'm using. I think shifting is a bit smoother and stays smoother longer with the synthetic. But who knows. Mostly it comes down to how much money I have when I am wandering the oil aisle at wally world

 

I have run synthetic blends after the break in period in most of my engines and never had any issues. This year though I tried the Rotella in the bike and I must say it does shift much nicer and seems quieter with that oil in it. Just my $.02