For a true progressive-rate spring, the Progressive Suspension 03-1394B and 03-1368B are the clearest matches in this selection; both are sold as pairs and list two spring-rate values. The Progressive Suspension 11-1527 is a progressive fork spring, not a coil-over spring. Hyperco’s coil-over options provide specified dimensions and single spring rates, so they are alternatives for buyers prioritizing coil-over specifications rather than progressive action.
| Product | Type | Key listed specification |
|---|---|---|
| Progressive Suspension 03-1394B | Progressive spring pair | 75/120 lbs./in |
| Progressive Suspension 03-1368B | Progressive spring pair | 105/150 lbs./in |
| Progressive Suspension 11-1527 | Progressive fork spring | 18.5-inch designation |
| Hyperco 1810B0350 | Coil-over spring | 2.5-inch ID, 10-inch length, 350 lb rate |
| Hyperco 1812B0125 | Coil-over spring | 2.5-inch ID, 12-inch length, 125 lb rate |
Progressive Suspension 03-1394B Spring Pair
This is a true progressive-rate spring pair, with a listed spring ratio of 75/120 lbs./in and a black finish. The two-rate specification makes it a better match for shoppers specifically seeking progressive springs than the fixed-rate Hyperco coil-over options below.
Best for: Buyers whose suspension setup calls for this spring’s two listed rates and who need a pair. Confirm the required dimensions and vehicle or suspension application before purchasing; those details are not provided in the supplied product features.
Progressive Suspension 03-1368B Spring Pair
The 03-1368B is another black progressive-rate spring pair, with a listed ratio of 105/150 lbs./in. Compared with the 03-1394B, its stated rate values are higher, making the listed specifications the most useful distinction between these two options.
Best for: Buyers whose application calls for the 105/150 lbs./in ratio and a pair of springs. Choose this over the 03-1394B only when its rate specification better matches the suspension requirements. The product details provided do not identify fitment or spring length, so verify those before ordering.
Progressive Suspension 11-1527 Fork Spring
This is a progressive-rate fork spring rather than a coil-over spring. Its listed features include a 18.5-inch designation, precision winding, and high-quality chrome silicon wire. Those details make it relevant to buyers looking for progressive front-fork springs, but not a direct substitute for a coil-over unit.
Best for: Riders shopping for a progressive fork spring whose application matches the product. Check dimensions and fitment against the suspension before buying; the supplied features do not list a vehicle application or spring-rate ratio.
Hyperco 1810B0350 Coil-Over Spring
The Hyperco 1810B0350 is a steel coil-over spring with a 2.5-inch inner diameter, 10-inch free length, and 350-pound spring rate. Unlike the Progressive Suspension products above, its listed specification gives one spring-rate value, not a progressive-rate range. It is useful as a dimensional and rate-specific coil-over option.
Best for: Buyers whose coil-over setup requires the listed diameter, length, and 350-pound rate. Avoid choosing it solely because you want progressive action; the supplied product information does not describe it as progressive. Confirm the required spring dimensions and rate for the intended suspension.
Hyperco 1812B0125 Coil-Over Spring
This Hyperco steel coil-over spring has a 2.5-inch inner diameter, 12-inch free length, and 125-pound spring rate. Its longer listed free length and lower listed rate distinguish it from the 10-inch, 350-pound Hyperco spring. The supplied details identify a single rate, not a progressive rate.
Best for: Buyers whose coil-over application calls for the listed 12-inch length, 2.5-inch inner diameter, and 125-pound rate. It is not the right choice for someone who requires documented progressive-rate behavior. Verify fit and suspension requirements before selecting it.
Buying Guide: How to Choose a Progressive Spring
Do you need a progressive spring or a coil-over spring?
These terms describe different things. “Progressive rate” refers to a spring whose resistance changes as it compresses. “Coil-over” describes a spring used around a shock absorber. The supplied listings include progressive suspension springs and separate coil-over springs with single listed rates. Do not assume every coil-over spring is progressive.
How should you compare spring rates?
Compare the rate specification with the requirements for your suspension, not just with another product’s number. The Progressive Suspension pairs list two values, while the Hyperco coil-over products list one. These formats do not provide enough information to establish that one spring is a direct replacement for another.
Which dimensions should you verify?
For the Hyperco options, compare the 2.5-inch inner diameter and the 10- or 12-inch free length with the application’s requirements. For products without supplied dimensions or fitment information, check the manufacturer’s application details before ordering. Also verify whether the listing is for a pair or a single spring.
What is the difference between a fork spring and a coil-over spring?
The 11-1527 is identified as a fork spring, while the Hyperco products are identified as coil-over springs. Select by the suspension component and application, not simply by the word “spring.” A fork spring is not automatically interchangeable with a coil-over spring.
Frequently Asked Questions
Which listed product is explicitly progressive rate?
The Progressive Suspension 03-1394B, 03-1368B, and 11-1527 are described as progressive-rate products in the supplied features.
Are the Hyperco coil-over springs progressive rate?
The supplied Hyperco features list single spring-rate values and do not describe progressive-rate behavior.
Which Progressive Suspension pair has the lower listed rates?
The 03-1394B lists 75/120 lbs./in, lower than the 03-1368B’s listed 105/150 lbs./in.
Is the 11-1527 a coil-over spring?
No. It is listed as a progressive-rate fork spring.
What should I check before buying?
Confirm spring type, dimensions, rate, quantity, and application fitment against your suspension requirements.