A reader asks:
“I’thousand looking to switch my Harley-Davidson Street Glide Special over to AMSOIL. Evidently the engine volition accept your synthetic 20W-50, but I’chiliad curious about what to employ in the primary and transmission. There are a lot of different combinations put out there on the internet. Some use gear lube in the transmission and chaincase. Some even use ATF in chaincase and claim they have great results. What is the best combination for my bike?”
For any Harley Twin-Cam engine, we highly recommend using AMSOIL Synthetic 20W-50 in “all three holes” (as they put it) for two essential reasons.
AMSOIL now offers defended fluid for Harley Davidson primary chain-cases and transmissions. These are called AMSOIL V-Twin Primary Oil and AMSOIL V-Twin Transmission Oil. Should one use these dedicated fluids? Or is AMSOIL V-Twin 20W-50 acceptable for principal and transmission utilise? There truly is no wrong answer. AMSOIL V-Twin 20W-50 is designed for engine, primary and transmission employ. It is certainly a highly competent and convenient option for all 3 components. For those that adopt a specialized fluid, the Five-Twin Primary and 5-Twin Transmission Fluids will certainly provide outstanding performance and protection.
See All Of Our Manufactures On Harley-Davidson Motorcycles And Synthetic Oil
AMSOIL V-Twin 20W-fifty Works (and works very well indeed)
AMSOIL 20W-fifty Synthetic Motorcycle Oil is specifically designed to withstand the rigors of engine, transmission and primary chaincase utilize. Look smooth, tranquillity shifting with maximum component life. It is contains additives to forestall wear and the 100% synthetic base oil will not shear downwards (sparse out). Therefore, it will not go out transmission or primary components vulnerable to accelerated wear.
AMSOIL has secondary recommendations of AMSOIL Severe Gear 75W-110 for the transmission and Astringent Gear 75W-140 for the primary, but the company themselves will tell y’all that there is absolutely no upside to using gear oil in these components rather than the 20W-l. Some may call back that they are using a thicker oil past using a gear lube. But call up that engine oils and gear lubes use different viscosity scales to preclude confusion.
What Most Gear Oil?
Allow’s wait at the bodily viscosity numbers of AMSOIL 20W-fifty Motorcycle Oil and AMSOIL Severe Gear 75W-90, 75W-110 and 75W-140. The manufacture standard for measuring viscosity is in “centistokes” at 100°C.
- “MCV”AMSOIL 20W-50:
- “SVG” Severe Gear 75W-90:
- “SVT” Severe Gear 75W-110:
- “SVO” Severe Gear 75W-140:
Every bit y’all tin can see, the 20W-l motorbike oil is relatively close to the 75W-110 in terms of actual viscosity. So those opting for a gear lube thinking that they are using thicker oil, really are non. Those using an 80W or 75W-90 in their transmissions are actually using a much thinner oil. The 20W-50 motorbike oil’southward viscosity is right in the “sugariness spot” for optimum operation in all three holes and the volumes of positive reviews nosotros receive back this up.
Gear lubes do contain heavy doses of “extreme pressure” additives which many believe preclude transmission wear and provide quieter operation. Again, AMSOIL 20W-50 Motorbike Oil is packed with additives specifically designed to preclude wear in clutches, gears, bondage and sprockets. At that place is absolutely no downside to going the 20W-50 route.
Some tout the use of automatic transmission fluid (ATF) in Harley master chaincases. Nosotros practise not recommend this choice. Over again, let’south look at actual viscosity numbers to dorsum this up. The viscosity of a typical ATF at 100°C is vii.5 centistokes. We submit that ATF viscosity is far too sparse for this application and think that the risk of long term wear is far too slap-up. AMSOIL 20W-50 has a viscosity of 18.5 centistokes.
Convenience: Ane Effective Product For Everything
The second principal reason that nosotros recommend using 20W-l motorcycle oil in the engine, transmission and primary chaincase is that yous can buy one product for everything. Therefore, you tin go along one product on mitt and bring one oil along on trips for pinnacle-ups. In determination, just does AMSOIL Synthetic 20W-fifty work exceptionally well in all 3 holes, information technology keeps things simple.