Determining the design of the counterbalance shafts and the crankcase
NOTE:
TECHNICAL INFORMATION
There are two different designs of the mass balance and the crankcase.
It is imperative to determine the designs because the assembly procedures differ.
When replacing, it is permissible to install the mass balance mounted on the wire spring in a crankcase with a bore of 13 mm for the intermediate gear.
There are two different designs of the mass balance and the crankcase.
It is imperative to determine the designs because the assembly procedures differ.
When replacing, it is permissible to install the mass balance mounted on the wire spring in a crankcase with a bore of 13 mm for the intermediate gear.
- Determine the design of the counterbalance shafts using the table.
Design of the counterbalance shafts Use of the counterbalance shafts Fixed counterbalance shaft 1 B48 technical update 0/1 Spring-loaded counterbalance shaft 2 B48 technical update 2 Spring-loaded counterbalance shaft 2 Possible in case of replacement for B48 technical update 0/1 - Read off the engine identification.
The last letter code of the engine identification (1) determines the design of the crankcase.
Engine identification Engine B48A20 A - B48A20 G B48 technical update 0/1 B48A20 P - B48A20 XXX B48 technical update 2 - Determine the diameter of the bore in the bushing (1)
for screwing on the idler gear.
- Prepare a commercially available caliper gauge (1)
.
- Measure the diameter of the bore with the caliper gauge (1) .
- Use the table to select the installation method.
| Design of the counterbalance shaft | Measured bore | Installation method |
|---|---|---|
| Fixed counterbalance shaft | 13.0 mm | Installing the counterbalance shafts (B48 technical update 0/1) |
| Installing the crankshaft (B48 technical update 0/1) | ||
| Spring-loaded counterbalance shaft | 13.0 mm | Installing the counterbalance shafts (B48 setting with spring balance) |
| Installing the crankshaft (B48 setting with spring balance) | ||
| Spring-loaded counterbalance shaft | 12.3 mm | Installing the counterbalance shafts (B48 technical update 2) |
| Installing the crankshaft (B48 technical update 2) |