Old Britts – Cylinder Head Rebuild Information
Download the complete PDF version using the green download button at the top right of this page for a detailed Old Britts technical article covering Norton Commando cylinder head rebuild information. This workshop reference discusses rocker arm spindle removal and installation, valve selection, lash cap use, valve stem preparation, leakage testing, valve lapping and practical methods for keeping parts organized during cylinder head service work.
This illustrated guide explains how rocker arm spindles are removed and installed with the cylinder head heated, including use of the factory slide hammer and an alternative spindle puller when the spindles are especially tight. It also covers correct spindle orientation for Commando and Atlas cylinder heads, along with a simple safety-wire checking tool used to confirm oil hole alignment in the rocker spindle flat.
Further sections provide valve information for Norton Commando 750 and 850 engines, including intake and exhaust valve sizes, lash cap purpose, the need to shorten valve stems when fitting caps and methods for checking final valve length. The article also covers valve leakage testing before dismantling, lapping valves with coarse and fine compound, manual and drill-assisted lapping methods, and the importance of keeping each valve matched to its freshly lapped seat.
Contents Include
- Rocker arm spindle removal and installation
- Heating the cylinder head before spindle work
- Factory slide hammer and spindle puller use
- Correct rocker spindle orientation for Commando heads
- Safety-wire tool for checking spindle oil hole alignment
- Norton Commando intake and exhaust valve information
- Valve lash cap purpose and valve stem shortening notes
- Valve leakage testing before and after service
- Valve lapping methods and compound selection
- Keeping valves, springs and seats correctly organized
