Part: Piston Rings (Standard / 0.5 mm over size / 1.0 mm over size) for Honda CL350 Scrambler / SL350 / CB350 – Sold Individually
Why You Need This: The Honda CB350 / CL350 Scrambler / SL350 engines are tough little machines, and we know of some 350's with thousands of miles on the clock that still run strong. Yet all engines need to be overhauled eventually as oil leaks happen and compression numbers drop. Many Honda CB350 / CL350 / SL350 engines do not need an overbore on the cylinders as they are within the factory service limits for a re-ring. If your cylinders measure up to be within the service limits (page 26 in the Honda Factory Service Manual), then a light hone followed with a fresh set of standard piston rings will get your Honda CB350 / CL350 / SL350 back to factory spec. However if you find the cylinders are over service limit (or are very close to being there), the cylinders will need to be bored oversize. This will require new oversize pistons and matching oversize piston rings along with a new wrist pin and retaining clips in order to correctly finish your rebuild. Luckily, in both cases, we got you covered with our modern piston rings designed to improve sealing, ease of install and ensure long service life.
Piston Ring kits are offered in three different sizes for the CB350 family of engines:
Standard (64 mm bore)0.5 mm Over Size1.0 mm Over Size
Standard (64 mm bore)
0.5 mm Over Size
1.0 mm Over Size
Our standard piston ring kit is designed to fit the factory Honda pistons in standard size (64 mm) used in the Honda CL350 Scrambler / SL350 / CB350 twin cylinder engines.
Oversize piston ring kits are available in 0.5 mm and 1.00 mm oversize, designed to fit factory Honda oversize pistons as well as our very own "Pulsar" series oversize pistons.
Each ring set includes:
A gas nitride coated forged steel top ring (silver). This is a hard coating on all surfaces of the ring which gives it increased wear resistance and a lower coefficient of friction on the cylinder walls.
Steel phosphate 2nd ring (black).
An easy-to-install modern nitride three piece oil ring, which makes installation onto the piston and cylinder assembly a LOT easier than the old style brittle cast iron one piece oil rings.
Piston ring sets are sold individually. One set is needed per piston, two sets per engine. We highly suggest adding the optional new wrist pin end clips and a fresh overhaul gasket kit to finish the rebuild right.
Installation Tip: Make sure to check the piston ring end gap on the compression rings prior to installation. Average gap is 0.008" (0.2 mm) to 0.016" (0.4mm) with a maxim gap of 0.032" (0.5 mm). The three-piece oil ring is installed with the wavy ring first then the thin rails are placed on the top and bottom of the spacer. The top two rings are specific to each groove, the shiny chrome ring goes in the top and the black ring is the second; these do not have an up or down and can be installed either way. Once on the piston, rotate the open ends of all the rings 120 degrees apart from one another. Thoroughly oil the rings and the cylinders prior to installation.
