Description
RFX Pro Series Armalite Rear Sprocket Yamaha YZ125-250 YZF250-450 99-23
RFX Pro Series Armalite sprockets are designed and tested at the highest level by top World and British championship race teams.
New dual ring design gives the ultimate sprocket performance, reduced weight thanks to a 7075-T6 aluminium centre and long lasting teeth life thanks to the high carbon steel outer.
Armalite sprockets also feature a hexagon drive interface between the inner and outer ring, this is revolutionary technology for sprockets and maximises drive between the two parts and reduces the force on the rivets to zero unlike the competition.
Pro Series Armalite Sprocket Features:-
- CNC 7075 Aerospace aluminium Inner ring
- HCS Outer Ring
- Hex-Drive location between inner & outer ring
- CAD designed profile for lightness.
- New style mud clearing grooves to reduce wear.
- Rigid design increases torsional strength.
- Colour anodised for that factory bike look.
| Bike | Year | Pitch | Part Number |
| YZ 125 | 99-01 | 520 | FXRS 31-48 |
| YZ 125 | 05-20 | 520 | FXRS 31-48 |
| YZ 125 | 02-04 | 520 | FXRS 31-49 |
| YZ 250 | 02-05 | 520 | FXRS 31-49 |
| YZ 250 | 99-01 | 520 | FXRS 31-50 |
| YZ 250 | 05-20 | 520 | FXRS 31-50 |
| YZF 250 | 01-04 | 520 | FXRS 31-48 |
| YZF 250 | 05-11 | 520 | FXRS 31-49 |
| YZF 250 | 12-20 | 520 | FXRS 31-50 |
| YZF 400 | 99 | 520 | FXRS 31-48 |
| YZF 426 | 00-02 | 520 | FXRS 31-48 |
| YZF 450 | 03-04 | 520 | FXRS 31-48 |
| YZF 450 | 10-13 | 520 | FXRS 31-48 |
| YZF 450 | 06-09 | 520 | FXRS 31-49 |
| YZF 450 | 14 | 520 | FXRS 31-49 |
| YZF 450 | 05 | 520 | FXRS 31-51 |
| YZF450 | 15-20 | 520 | FXRS 31-48 |
| WRF 250 | 07-14 | 520 | FXRS 31-50 |
| WRF 250 | 01-06 | 520 | FXRS 31-52 |
| WRF 400 | 99-01 | 520 | FXRS 31-50 |
| WRF 426 | 00-02 | 520 | FXRS 31-50 |
| WRF 450 | 03-20 | 520 | FXRS 31-50 |
Fitting Instructions
- Start with bike on a stand with the rear wheel raised from the ground.
- Remove chain and wheel from bike.
- While holding the Hex key loosen the nuts with a spanner.
- Remove all nuts and old sprocket.
- Clean around the hub making sure clean and free of debris.
- Take the new sprocket and place on hub ensuring a nice snug fit making sure the bolt holes are in position.
- Clean sprocket bolts & nuts.
- Apply Blue Loctite to each bolt and insert in the holes.
- Thread nuts on to bolts by hand ensuring locking seals are intact and in good condition.
- Hold Hex key in place and tighten nuts even pattern.
- Torque nuts and bolts in accordance to your owner’s manual.
- Put wheel back in bike making sure chain is corrected aligned and tightened to manufacturer’s specification.