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Honda Technical Information

Notes on maintenance (frame)
RS125R / RS250R
Body maintenance
  Frames should be checked if the machine was subjected to a large impact force when fallen down. Even slight falling down events may result in exposure to impact force higher than expected.
In particular, careful check should be made for cracked weld or deformed parts.

Wheel bearings
  Wheel bearings should be so installed that the wheel turns smoothly when mounted in vehicle, instead of when not. It is recommended that the distance collar be slightly stiff between inner bearings at the both sides when the wheel is not mounted in vehicle. The distance collar should not be free inside the hub.  

Caliper cleaning
  Calipers should be cleaned using household detergent, instead of brake cleaner or gasoline. Use of brake cleaners or gasoline would cause swelled or deformed caliper seals, resulting in stuck caliper pistons.  

Tightening engine mounts (RS125R)
  Tightening engine mounts (RS125R)
The year 1998 and later RS125R has changes to engine mount upper and lower adjust bolts/lock nuts tightening torque in order to improve rigidity.

Description -'97 '98-
Adjust bolt (upper/lower) 0.4kgf.m 1.5kgf.m
Lock nut (upper/lower) 2.6kgf.m 4.0kgf.m
  The year 2000 and later RS125R has an alteration to rear swing arm pivot bolts (increased wall thickness) with torque remaining unchanged. The year 2001 and subsequent RS125R has an alteration to rear arms, ribs behind pivots, and rear suspension mount shape in order to improve overall rigidity.  

Front suspension inner pressure adjustment
  Repetitive suspension strokes will cause air ingress into the inside from the seals. This will result in increased inner pressure, leading to suspension which gives counter-force as compared with the (in particular initial) stroke.
To solve this problem, it is recommended that the suspension covers be removed with the stand raised to release suspension inner pressure. This gives the suspension willingness to move from the beginning to run.

(Colder ambient temperatures cause harder fork oil, resulting in degraded driving comfort in the beginning of riding. In this case, it is recommended that suspension damping be reduced by 2 to 3 notches for both compression and elongation sides to create riding comfort from the beginning.
Also, when increased vehicle speeds is making fork oil softer, your standard settings should be restored, and then your setting be sought.)


Front axle torque management
  Adjustment should be made so as to secure proper torque put onto the axle.
Insufficient tightening torque on axle split-tightening bolts or insufficient torque to the axle caused by ingress of foreign matter to axle holder splits largely degrade the front stability.
If you are faced with a problem as to where to proceed in suspension setting, check should be made.
Top and bottom bridges, handle holders, and steering damper holders securing the front fork should be tightened to a specified torque. Extremely high or low tightening torque will greatly change suspension feeling, making setting impossible.
Toque values specified in the manual should be strictly followed.
Item RS125R RS250R
Axle shaft split tightening 2.2kgf.m 2.2kgf.m
Top bridge split tightening 2.3kgf.m 2.3kgf.m
Bottom bridge split tightening 2.3kgf.m 2.3kgf.m
Handle holder bolt 2.2kgf.m 2.2kgf.m
Steering damper clamp bolt 1.0kgf.m 1.0kgf.m
  *Specified torque above is given for dry conditions. Do not tighten under wet conditions.  

Rear axle shaft installation/removal
  With the changes to rear swing arms, the 250 class also has changes to rear axles employing self-locking nuts like the 125 class.
These self-locking nuts provide higher tightening torque, so care should be exercised not to destroy threads. Any dirt or foreign particle should be removed from threads before tightening.
(tightening torque: 7.0kgf.m for RS125R and 8.2kgf.m for RS250R)

Coupler cleaning
  Especially in older machines, corrosion or dirt inside the couplers in the electrical system may cause electrical disconnection.
One example of these problems is engine misfires which may occur after rainfall.
To avoid these problems, couplers should be periodically removed for cleaning (especially after rainfall).

When couplers are replaced, they should be inserted until click noise occurs. Unless secured, they may come off because of vibration during running.


For driving safety
  The 2001 and later year 125 and 250 has had caliper bolts holed for wire locking.
Wire lock should be made before running. Wire lock does not prevent loose bolts from loosening further, but if you have a usual practice to do wire lock, you are likely to find loose fasteners before running.
If brake calipers should fall off during running, serious crashes will result. Consumers owning 2000 and earlier year models should have their calipers replaced with new ones holed for wire locking.
  Wire lock holed bolts (common to the 125 and 250)  
Part number Discription
90111-NX4-710 Bolt, flange 10x31

Note on RS250R
Position changes
  The 2001 year RS250R has positions largely changed. Use of the shorter tank in length and narrower clearance between the handle and the seat allows riders of any physique to aggressively control the machine.
However, a rider of large physique would have a difficulty in holding the lower half of the body during braking, leading to excessive force applied to the handle and degraded turning ability. To solve this problem, pads or something should be attached to the tank to secure that the rider can hold his/her lower half of the body during braking.

Ride height
  For the 2001 year model, since the engine is mounted at a height about 50mm higher than the 2000 year model, the center of gravity is 40 to 50mm higher than the previous model.
For setting a ride height, lowered ride height at the front and rear would provide nimble steering feeling like the 2000 year model. However, significant lowering of vehicle height should not be done in order to obtain the 2001 year model's turning ability.
The 2001 year model is designed to provide turning ability taking into consideration center of gravity , dimensions, and body rigidity, so care should be exercised to greatly alter the specifications.