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Honda Pistons - RS125 and RS 250

piston cir-clip installing tool. You will want one of these!
No more wrist-pin woes!
C-Clipper install wrist-pin clips in seconds CLICK HERE for more information

For some basic information on installation of pistons and rings and notes on our
findings on the RS250 p
iston/ring failures. CLICK HERE

Wossner - High Performance Pistons

As we all are aware Honda OEM pistons for our 2-stroke GP machines have doubled in price and then doubled again and some racers have had issues with the new OEM pistons especially in the RS250 Honda. We have been looking for a solution.

W�ssner manufacturers German engineered high quality forged pistons for 2-stroke and 4-stroke competition engines. Piston kits which include rings, clips, and pin.
4-stroke pistons are supplied with custom DLC (Diamond-Like Carbon) coated wrist pins, providing anti-friction, high RPM motors.

Honda RS125 and RS250
WOS-8244DA Wossner Honda RS125 GP Domed top 53.94mm piston

These pistons now only available with the WPC-TREATMENT - Metal Surface treatment that we started having done on our Wossner Pistons. Yamaha has been having this done to all there TZ pistons since 2003 Check out

WOS-8244DB Wossner Honda RS125 GP Domed top 53.95mm piston
WOS-8244DC Wossner Honda RS125 GP Domed top 53.96mm piston

WOS-8245DA Wossner Honda RS125 GP Flat top 53.94mm piston
WOS-RSA5400 Wossner Honda RS125 GP Ringset 54.00 X 0.8mm

We have received positive results form these pistons installed in both the RS125 and RS250 Honda machines.
For install of coated piston it has been recommended to lightly red Scotch Brite the pistons skirt in a cross hatch, properly dress ring groove, measure end gap, clean and assemble. Properly warm up engine at low RPMs for 2 heat cycles and always be sure motor is completely warmed before heading out to the track and properly setup either with duct tape or a thermostat system to stay at proper operating temperature.

Honda CRF250 & CRF250X
Wossner Honda CRF250 & CRF250X 13.5:1 '06- "09, 77.95mm #8656DA Piston kit (rings- 780XAS, PIN- WP959, CLIP- CW16) Clearance:0.04mm

For all those racers that have been looking for
Domed Top "A" pistons for your 125 motor!

Honda RS125 new dome piston are now available with 0.8mm flat piston ring.
The position pin is in the middle.
Piston kit includes
a ring, ris pin and circlips.

VT23105A Vertex 23105A Honda RS-GP95-97 125cc D. 53.94mm (02V) Piston w/ring (53007805400),
pin (711127) and clips ( 72071)

VHM Solid Billet Piston for Honda RS125/RS250

With many years of experience in research and design in 2 stroke piston, has lead us in the development and manufacturing of piston machined from a solid billet material. This gives us the great possibility to change quickly to any shape. Other improved material properties can be tested quickly without high cost and we have great control over dimensional accuracy.

VHM billet pistons are 100% CNC machined from high quality solid billet material specially manufactured according our specifications and material properties. The piston feature internal and external machining to unique shapes for an increased rigidity.

The billet piston are machined on every surface allowing for all unnecessary weight to be removed. It can deliver the highest uniformity of material thickness on skirts and the general body. The piston features a special skirt shape which will result in a cylindrical shape during operating temperature with the optimum clearance for less friction giving the best performances.

VHM solid billet piston kits come completely with piston, piston ring, piston pin and clips.


  • Fully CNC machined
  • Precision machined ring grooves
  • Bottom oilers for pin lubrication
  • Precision machined for exact pin clearince
  • VHM special high quality billet aluminum alloy
  • Unique internal shape for increased rigidity and optimum strength in critical stress areas
  • Cylindrical shape during operating temperature
  • Tapered piston pin for reduced weight

Model � piston
VHM piston kit
Honda RS125/RS250 53,94 APHO12511693B 53.94mm Piston,
with APR540.8 Piston ring, APP1545 Piston Pin,
APC151.0 Piston clip

PI13116-01 VHM piston kit flat �53.94-�53.95 for 0.7 mm piston ring

New flat top piston with 0.70 mm piston ring.

Must be used with short piston pin, PIP711162!
Can be used for Honda RS125 and RS250.
Piston weight 117 gram.

Content: Piston + 0.7 mm piston ring + 2 clips

PIP711162 Piston pin �15 short 41 mm special

Piston pin weight 28,2 gram.

HRC Flat Top "A" Kit Pistons SOLD OUT No Longer Available from HRC

HRC-NX4-0601 NX4/NX5/NXA FLAT PISTON-C 0.7 - use 13121-NJBA-003 FLAT PISTON RING $328.13

13121-NJBA-003 FLAT PISTON RING .07mm