WÖSSNER Connecting Rod Kit for YAMAHA WRF 450, YZF 450 2023-2026

On YAMAHA WRF 450, YZF 450 from 2023 to 2026, the WÖSSNER P4088-R connecting rod kit fits in place of the original part. Between the piston and the crankshaft, the connecting rod takes every combustion and every climb through the revs. Replacing the rod, crank pin and bearing in time prevents engine failure.

Specifications

• Brand: WÖSSNER
• Manufacturer part number: P4088-R
• Engine: 4-stroke

When to replace it?

• Vertical play at the big end at top dead centre.
• Side play out of tolerance, signs of overheating (bluing).
• Vibration and dull noise from the bottom end.

During a bottom end rebuild, at the intervals in the service manual, and without delay as soon as play appears at the big end.

Fitting tips

1. Replacing a connecting rod means pressing the crankshaft apart and then realigning it: with a dial indicator, you check the run-out, i.e. the deviation in rotation measured at the end of the shaft, which must stay within a few hundredths of a millimetre at most. Leave this job to a properly equipped workshop if you don't have a press and a truing stand.
2. Replace the crankshaft bearings and oil seals at the same time.
3. Check the big-end side play after assembly.
4. Close up the engine with a complete engine gasket kit and tighten to the manufacturer's torque.
5. Check the gearbox bearings, then fill up with fresh oil and fit a new spark plug.

Why WÖSSNER?

Wössner is a German family business based in Weil am Rhein and founded by Eckart Wössner, a former racer from the 1970s. It has been making its own forged pistons since 1994, from blanks produced in its own forge, and Wössner pistons are used in Supercross as well as in MXGP.

Spare parts and items to plan

• Crankshaft bearings and seals : see the selection
• Complete engine gasket kit : see the selection
• Gearbox bearings : HOT RODS TBK0068 · HOT RODS TBK0107
• 4-stroke engine oil : LIQUI MOLY 10W40 1 L · MOTUL 10W50
• Spark plug : NGK 4218 · NGK 96067

Frequently asked questions

Can I fit the connecting rod myself?
Yes, if you have a press and a crankshaft truing stand; otherwise, an engine workshop can do it for you.

What else should I plan for?
The crankshaft bearing and seal kit, the complete engine gasket kit, the gearbox bearings if required, engine oil and a spark plug.

Compatibility

Check the exact model and year of your bike in the list below before ordering.

Fits:
YAMAHA WRF 450 2025
YAMAHA WRF 450 2024
YAMAHA YZF 450 2026
YAMAHA YZF 450 2025
YAMAHA YZF 450 2024
YAMAHA YZF 450 2023