Progressive Suspension has focused exclusively on American V-twin suspension since 1982, and its Monotube fork cartridges and 400/970/970G shock series are among the most common upgrades on baggers and Softails. For most riders the stock rear shock is the single worst part on the bike — this is the fix.
Elevate your Harley-Davidson's ride quality with Progressive progressive-rate fork springs, engineered to deliver a superior suspension experience. These springs efficiently absorb minor road imperfections while providing the necessary resistance to minimize front-end dive during braking, ensuring a more stable and comfortable journey.
Why riders pick this
Progressive-rate design for balanced feel
Reduces front-end dive during braking
Precision wound for consistent performance
Improves overall ride stability and comfort
Progressive's progressive-rate fork springs are a smart upgrade for any Harley-Davidson rider looking to improve their bike's handling and comfort. The precision-wound design means you get a consistent and reliable performance that adapts to various road conditions. This technology translates into a more controlled feel when cornering and a significant reduction in the unsettling front-end dive often experienced under hard braking, boosting rider confidence.
Superior Front-End Control
Progressive-rate spring design handles both small and large impacts
Actively reduces front-end dive under braking for better stability
Precision wound construction ensures consistent and reliable performance
Available in different versions to match rider weight and load
Setting Up Your Suspension
Optimizing your Harley-Davidson's front suspension is key to a better ride. These Progressive fork springs offer a tangible upgrade, but selecting the correct version (Standard or Heavy Duty) for your specific model and riding habits is essential. Always consult your bike's specifications or our Shop by Bike tool to ensure perfect compatibility and performance.
Specifications
Brand: Progressive
Manufacturer Part #: 11-1578
Weight: 4.8 lb
Category: Suspension / Fork Springs
WARNING: Cancer and Reproductive Harm — California Prop 65. www.P65Warnings.ca.gov
Common questions
What is the difference between Standard and Heavy Duty springs?
Standard springs are designed for typical rider weight and load, while Heavy Duty versions are stiffer to accommodate heavier riders, passengers, or loaded touring.
Will these springs reduce the front-end dive under braking?
Yes, the progressive rate design resists initial compression, which minimizes dive while still absorbing road imperfections for a smoother stop.
Do these springs require a special fork oil?
While not strictly required, using fresh, high-quality fork oil with the recommended viscosity for your model will complement these springs and optimize your front suspension's performance.
Ordering from Vtwinbikers
Brand new, sourced through authorized US distribution — never used, never grey-market.
Not sure it fits? Use Shop by Bike to filter by your year and model, or email us and we will confirm before you order.
Harley-Davidson and Indian Motorcycle is all we do, so you are talking to people who ride what you ride.
BRAND
Progressive
TYPE
Fork Springs
SKU
T14-669304
WEIGHT
4.8 lb
Please contact us to confirm fitment for your specific motorcycle, or check the product title for compatibility notes.
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May 6, 2018
Great Stock Replacement
Great replacement for stock, I ride an 05 XL that was clapped out in the front and when sat on the drop was close to bottoming out. I had to cut the PVC spcer in half to get the cap back on the top of the fork, but other than that the product is great. I replaced out with 20WT and when sitting on the bike it drops 11/2. Bike doesnt dive under breaking and handles far better. Best bang for the buck without a total rebuild or spending thousands on inverted forks.
Progressive Progressive-Rate Fork...
$510.000,00
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