Rear Suspension Adjustments; Rear Suspension Spring Pre-Load - Honda CRF450RX 2020 Owner's Manual & Competition Handbook

Rear Suspension Adjustments

Rear Suspension Adjustments

The rear suspension can be adjusted for the rider's
weight and riding conditions by changing the
spring pre-load and the rebound and compression
damping.
The rear suspension assembly includes a damper
unit that contains high pressure nitrogen gas. Do
not attempt to disassemble, service, or dispose of
the damper; see your dealer. The instructions
found in this owner's manual are limited to
adjustments of the shock assembly only.
Puncture or exposure to flame may also result in an
explosion, causing serious injury.
Service or disposal should only be done by your
dealer or a qualified mechanic, equipped with the
proper tools, safety equipment and an official
Honda Service Manual.
If your CRF is new, put enough part-throttle break-
in time (about 1 hour) on it to ensure that the
suspension has worked in.
146
Adjustments for Competition

Rear Suspension Spring Pre-Load

Pre-load should be adjusted when the engine is
cold because it is necessary to remove the muffler.
An optional pin spanner is available for turning the
shock spring lock nut and adjusting nut to adjust
spring pre-load.
1. Place your CRF on an optional workstand or
equivalent support with the rear wheel off the
ground.
2. Remove the subframe (page 39).
3. Remove the right muffler joint pipe
(page 129). (CRF450RWE only)
4. Check that the spring pre-load is adjusted to
the standard length. Adjust as necessary by
loosening the shock spring lock nut (1) and
turning the adjusting nut (2).
Each complete turn of the adjusting nut
changes the spring length by 0.06 in (1.5 mm).
After adjustment, hold the adjusting nut and
tighten the shock spring lock nut to the
specified torque:
32 lbf·ft (44 N·m, 4.5 kgf·m)
(3)
(1)
(2)
(1) shock spring lock nut (3) pin spanners
(2) adjusting nut (4) spring length
Refer to the following pages for the installation
procedure of the removed parts:
• air cleaner case and air cleaner connecting
tube: page 41
• subframe: page 40
To increase spring pre-load
Loosen the shock spring lock nut using the
optional pin spanners (3) and turn the adjusting nut
to shorten the spring length (4). Do not shorten to
less than:
(CRF450RX)
Standard (Medium) spring (296.9 lbf/in (52 N/mm)):
8.94 in (227.0 mm)
Optional Soft spring (285.5 lbf/in (50 N/mm)):
8.94 in (227.0 mm)
Optional Stiff spring (308.3 lbf/in (54 N/mm)):
9.07 in (230.5 mm)
(CRF450R/RWE)
Standard (Medium) spring (319.8 lbf/in (56 N/mm)):
9.06 in (230.0 mm)
Optional Soft spring (308.3 lbf/in (54 N/mm)):
9.07 in (230.5 mm)
Optional Stiff spring (331.2 lbf/in (58 N/mm)):
9.13 in (232.0 mm)
(4)