The Long Haul Part 2: Servicing the Engine
Texas to Ohio to Minnesota and Back Again on a 1974 Honda CB450
Section 1: The Bottom End
The heart of a motorcycle is its engine, and is naturally the first place to start when making your way through the overhaul process. Different bikes require removing different parts to access the bottom of the motor.
- Oil Drain Plug
- Gas Tank
- Shift Lever
- Kick Start Lever
- Left Foot-Peg
- Mufflers & Header Pipes
- Chain Cover & Clutch Cable
- Rotor Cover
- Right-Side Engine Cover
- Carb & Intake Manifolds
- Valve Covers
- Points Cover
Once all the oil was drained and the engine covers were removed we could tend to the lower parts of the engine starting with the right side - specifically the clutch and the oil filter. We fitted the clutch with new friction disks and springs and we gave the oil filter a thorough cleaning. The engine covers were then reassembled with fresh gaskets and a set of stainless steel Allen-head bolts.
Rebuilding the clutch on a Honda CB450 is a fairly straightforward process, and is similar to most bikes of this era. Although the centrifugal oil filter is found on a number of early Honda CB models, this feature is fairly unique to these bikes. To see how it’s done in detail, watch our video showing how to clean centrifugal oil filter.
Section 2: The Top End
Once the bottom end was buttoned up we moved on to the top side of the engine, specifically the cam-chain adjustment, cam lobe inspection, and valve tappet clearance check and adjustment. No special tools are required for this part of the procedure other than a set of feeler gauges. These maintenance procedures are standard and should be carried out at Honda’s recommended service interval. Instructions can be found in the Honda Factory Service Manual
The last step in the engine tune-up process is setting the ignition timing, but before we do that we will inspect and/or replace all of the major electrical components on the bike. So stay tuned for the third installment of our Long Haul CB450 Project: The Electrical System