Below you will find the best synthetic oil for a 1991 Harley-Davidson FLST Softail. Maximize your vehicle's potential with 100% full synthetic oil that is made in the USA! For more than the past 50 years, AMSOIL has perfected the art of maximizing efficiency and engine life. The advanced synthetic formulas deliver superior protection from heat, friction, and wear, keeping engines as good as new for miles. Upgrade to AMSOIL today and experience better performance, reliability, and reduced oil consumption. Click add to cart for more details. Sign up as a preferred customer and get discounts and more! The oil type, capacity and oil filter (if available) are listed below and verified for accuracy. Upgrade now!
Recommended oil for my 1991 Flst Softail
| Product Name | Product Description | Capacities | Product |
|---|---|---|---|
| Engine Oil 20W-50 Synthetic V-Twin Motorcycle Oil |
This 20w-50 motorcycle oil for your 1991 Harley-davidson Flst Softail is a top oil for those who want the best protection and extend the life of the engine. Top research goes into this lube to protect air cooled engines, wet-clutch lubrication, and even protects when your motorcycle is in storage. Offers great protection for short trip usage as well. Protects gears, chains and prevents rust. Meets or exceeds the requirements of both foreign and domestic motorcycles. Made in USA. |
MCVQT-EA
Add To Cart  Add To Cart |
|
| Primary Chain Case Oil 20W-50 Synthetic V-Twin Motorcycle Oil |
This 20w-50 motorcycle oil for your 1991 Harley-davidson Flst Softail is a top oil for those who want the best protection and extend the life of the engine. Top research goes into this lube to protect air cooled engines, wet-clutch lubrication, and even protects when your motorcycle is in storage. Offers great protection for short trip usage as well. Protects gears, chains and prevents rust. Meets or exceeds the requirements of both foreign and domestic motorcycles. Made in USA. |
MCVQT-EA
Add To Cart Add To Cart |
|
| Primary Chain Case Oil Synthetic V-Twin Primary Fluid |
This is an awesome fluid for bikers who want a dedicated primary chaincase lubricant. Protect your 1991 Harley-davidson Flst Softail with the best fluid made in the USA. |
MVPQT-EA
Add To Cart Add To Cart |
Recommended oil filters for my 1991 Flst Softail
| Product Name | Product Description | Product |
|---|---|---|
| AMSOIL EaOM Chrome Motorcycle Oil Filters | This is a great motorcycle oil filter for the 1991 Harley-davidson Flst Softail. Made in the USA. |
EAOM135C-EA
Add To Cart Add To Cart |
| AMSOIL EaOM Motorcycle Oil Filters | Great oil filter for your 1991 Harley-davidson Flst Softail. Check out our synthetic oil for your motorcycle as well. |
EAOM135-EA
Add To Cart Add To Cart |
Synthetic engine oils keep your engine cool and clean, decreasing friction with low viscosity lubricants and detergents and antioxidants to keep gunk and corrosion at bay. Check out this testimonial by Tim on July 13, 2023. "My FLHTCU now has 72000 miles on it. From the first 600-mile oil change, this is the only oil I have used. My oil is changed every 5000 miles. Every time I change the oil, I submit a sample for analysis. Each time, it comes back clean. At my last full service, I did a cylinder leak-down test, and the results returned 5%. Outstanding for an air-cooled engine at 70000 miles! Best oil on the market."
