Can castrol hypoy c lubricant be used in primary on roadking or sportster

You engine uses three quarts of 20W50 oil. The primary and transmission share the same oil and it uses about a quart of oil. One the late model Big Twins, you can use H-D's Syn 3 in all areas. Not sure about the Sportster. I've always used the H-D primary/transmission lubricant for Sportsters. If you wish to use any other brand of lubricant, you need to go to their website and check to see what they say use in what area. Some of the other popular lubricants are Amsoil, Royal Purple, Mobil V-Twin, and Red Line.

Good Luck
Steve

On your Sportster, the primary oil is not fed by the oil pump. It is not even part of the oiling system of your bike. You manually put the oil in the primary by pouring it in the hole where you check your primary chain tension. The maintenance schedule on your bike suggest that the oil in the primary be changed every 5000 miles. The primary holds approximately a quart of oil. The oil that lubricates your primary also lubricates your transmission. So, if your primary case was dry, your transmission was running dry as well.

Good Luck
Steve

Your bike came with H-D 20W50 Syn3 engine oil in the primary. You can run other brands as well but check the manufacturers website for compatibility. In your Sportster, the clutch and transmission share the same lubricant. You need to make sure that the oil you use has the frictional characteristics suitable for use with the wet clutch.

Good Luck
Steve

I think the later models are designed to use the same type of oil in both the engine and the prmary/transmission. But, I have never agreed with this. I use H-D Syn 3 20W50 oil in the engine but I prefer to run either Harley's primary and transmission lube or one of the other manufacturers lubricants in the transmission. If you use another manufacturer's lubricant, go to their website and check for compatibility for use in your Sportster.

Good Luck
Steve

The primary case is not marked. The book says that between 32 and 40 ounces of oil is to be used in the primary/transmission case. This oil lubricates both the primary chain and sprockets as well as all the gears in the transmission. The oil will not be visible inside the case. If it were, there would be too much oil and it would make the clutch "drag" making it impossible to find neutral with the engine running. The sprockets and chain are lubricated by a mist of oil generated by the starter ring gear on the outer clutch drum slinging the oil all in the primary case when the engine is running.

Some of the older Sportsters had a threaded hole with a screw in it towards the bottom of the forward end of the case. One would remove the screw and fill the primary until it started to run out of the hole.

Good Luck
Steve

Harley-Davidson recommends their 20W50 petroleum based oil for the engine. You can use the H-D Syn 3 20W50 synthetic oil in the engine but I don't recommend it in the primary/transmission area. You can use any 20W50 oil as long as the API rating has a "C" rating for use in diesel engines. Look for the round circle somewhere on the container that had the API initials in it. It should say something like "SJ/CG". What you're looking for the "C" rating. If you wish to use a specific brand of oil, got to their website and look for their recommendations.

In the transmission, Harley recommends their Semi-Synthetic Primary and Transmission lubricant for Sportsters. The lube lubricates both the primary and the transmission on the Sportster. I don't recommmend full synthetic transmission lube on any bike built before 1995 as it will cause the gears to run noisey. In 1995, Harley changed the back cut on the gears and this made use of full synthetic lube more quiet running. Of course, you can use the full synthetic from a lubrication view point. It's just a bit noisey for my taste.

Whatever you use, make sure you go online and check the manufacturer's suggestion for use.

Good Luck
Steve

The lubricant in the primary is also the transmission lubricant. I've always used H-D primary transmission lubricant for Sportster. It takes one quart.

The transmission and primary are lubed by the same lubricant. You pour one quart into the inspection hole at the top of the primary cover. Use H-D primary & transmission lube for Sportsters.

I assume that by the term "transfer case", you're talking about the primary drive and transmission on your Sportster. The lubricant that you pour into the primary case also lubes the transmission. Not so on a Big Twin as they each have their own lubricants.

On the Sporty, theres a drain plug on the bottom of the primary case near the rear end of it. I'm pretty sure it uses a Torx driver to remove it. Drain the oil and refill with H-D primary & trans lube for Sportsters. Remove the derby cover at the rear of the primary cover and fill the primary until the oil level is even with the clutch pressure spring with the bike standing straight up. Replace the derby cover.

10 to 50 SAE is ok