The output shaft spacers help keep the play between the gear cogs, otherwise known as the end float, to a minimum to help the gears engage cleanly. The spacers on pre EFL PX motors only have 1 stabilising tab and the later spacers (post Lusso) have 4. The later EFL version can be retro fitted to the earlier PX motors.
The PX EFL output shaft requires the use of at least 2 spacers and also 2 circlips, one of each being at either end of the gear cluster. The more stable PX EFL gearbox parts are usually used in tuned PX motors. Due to the higher power levels produced by the more performance orientated motors the correct clearances between the gear cogs becomes essential.
To enable a more precise shaft end float distance, to the hundredths of a millimetre, to be achievable SIP have produced finer grades of gear box spacer to complement the existing range of sizes produced by PIAGGIO.
Unfortunately the dimensions of PIAGGIO standard sizes vary widely and the same part number often times comes in 3-4 different material thicknesses. To stay clear of unwanted variances we now also manufacture standard sizes. Your gear box will thank you in the end for the quieter (and longer) life.
Helpful Hint: The end float distance of your output shaft assembly should be between 0.15 and 0.4mm when it is newly put together. If you are checking it during a major service it should till be under 0.5mm otherwise you will require new (thicker) spacers...
SIP-TIP: The feeler gauge to measure the end float of your output shaft makes this job a lot easier. It is available at our shop, Art.-Nr.60824000. Do not forget to order a new cruciform, selector rod and fresh gear box oil to complete the job properly.