Progressive Springs increase in rate late in stroke to provide additional bottom-out support and open up the use of coil shocks on frames previously only suited to air shocks.
MRP - PROGRESSIVE SPRINGS
PROGRESSIVE SPRINGS
Progressive Springs increase in rate late in stroke to provide additional bottom-out support and open up the use of coil shocks on frames previously only suited to air shocks.
As with our Enduro SL springs, these springs are offered in a single free length per rate that fits most shocks from 200 (7.875") to 230mm. They accomodate up to 65mm of shock stroke. A 38mm ID fits our Hazzard shock and Rock Shox models natively, and spacer kits are available to use with other makes and models.
Please refer to our Technical Features tab for Spring Rate and Length Information
See compatibility on MRP's Coil Spring Spacer page. Some shock length and spring rate combinations require spacers to increase the total effective spring length and engage the threading on the shock body and to account for allowable max preload. Reference the listed free lengths and measure your shock to make sure any spring will fit.
MRP - PROGRESSIVE SPRINGS
SPRING RATE AND LENGTH INFO
300+
Effective base rate: 300 lb/in
Approximate linear-spring rate equivalent at 25% sag (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 275
...on 55mm / 57mm (2.25") stroke shock: 275
...on 60mm stroke shock: 300
...on 63mm (2.5") / 65mm stroke shock: 300
Approximate linear-spring rate equivalent at 90% travel (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 325
...on 55mm / 57mm (2.25") stroke shock: 325
...on 60mm stroke shock: 400
...on 63mm (2.5") / 65mm stroke shock: 400
Dimensions:
1.5" ID, 126mm
350+
Effective base rate: 350 lb/in
Approximate linear-spring rate equivalent at 25% sag (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 350
...on 55mm / 57mm (2.25") stroke shock: 350
...on 60mm stroke shock: 350
...on 63mm (2.5") / 65mm stroke shock: 350
Approximate linear-spring rate equivalent at 90% travel (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 375
...on 55mm / 57mm (2.25") stroke shock: 400
...on 60mm stroke shock: 400
...on 63mm (2.5") / 65mm stroke shock: 400
Dimensions:
1.5" ID, 129mm
400+
Effective base rate: 400 lb/in
Approximate linear-spring rate equivalent at 25% sag (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 400
...on 55mm / 57mm (2.25") stroke shock: 400
...on 60mm stroke shock: 400
...on 63mm (2.5") / 65mm stroke shock: 400
Approximate linear-spring rate equivalent at 90% travel (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 450
...on 55mm / 57mm (2.25") stroke shock: 450
...on 60mm stroke shock: 450
...on 63mm (2.5") / 65mm stroke shock: 475
Dimensions:
1.5" ID, 129mm (+/- 2.5mm) length
450+
Effective base rate: 450 lb/in
Approximate linear-spring rate equivalent at 25% sag (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 425
...on 55mm / 57mm (2.25") stroke shock: 425
...on 60mm stroke shock: 425
...on 63mm (2.5") / 65mm stroke shock: 425
Approximate linear-spring rate equivalent at 90% travel (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 500
...on 55mm / 57mm (2.25") stroke shock: 500
...on 60mm stroke shock: 500
...on 63mm (2.5") / 65mm stroke shock: 525
Dimensions:
1.5" ID, 134mm (+/- 2.5mm) length
500+
Effective base rate: 500 lb/in
Approximate linear-spring rate equivalent at 25% sag (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 475
...on 55mm / 57mm (2.25") stroke shock: 475
...on 60mm stroke shock: 475
...on 63mm (2.5") / 65mm stroke shock: 475
Approximate linear-spring rate equivalent at 90% travel (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 575
...on 55mm / 57mm (2.25") stroke shock: 575
...on 60mm stroke shock: 600
...on 63mm (2.5") / 65mm stroke shock: 600
Dimensions:
1.5" ID, 137mm(+/- 2.5mm) length
550+
Effective base rate: 550 lb/in
Approximate linear-spring rate equivalent at 25% sag (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 525
...on 55mm / 57mm (2.25") stroke shock: 525
...on 60mm stroke shock: 525
...on 63mm (2.5") / 65mm stroke shock: 550
Approximate linear-spring rate equivalent at 90% travel (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 650
...on 55mm / 57mm (2.25") stroke shock: 650
...on 60mm stroke shock: 675
...on 63mm (2.5") / 65mm stroke shock: 675
Dimensions:
1.5" ID, 141mm (+/- 2.5mm) length
600+
Effective base rate: 600 lb/in
Approximate linear-spring rate equivalent at 25% sag (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 550
...on 55mm / 57mm (2.25") stroke shock: 550
...on 60mm stroke shock: 550
...on 63mm (2.5") / 65mm stroke shock: 575
Approximate linear-spring rate equivalent at 90% travel (rounded to nearest 25 lb. increment):
...on 51mm (2.0")stroke shock: 675
...on 55mm / 57mm (2.25") stroke shock:700
...on 60mm stroke shock: 700
...on 63mm (2.5") / 65mm stroke shock: 725
Dimensions:
1.5" ID, 143.5mm (+/- 2.5mm) length