Description

Honda CB250, CL250, CB350, CL350 Workshop Manual

I’ve seen too many backyard rebuilds where a guy pulls a head bolt to 50 ft-lbs because “it felt tight.” Then the head warps, gasket blows, and four hours of labor go into fixing what a number in a book would have prevented. That’s why this manual exists. It’s the original Honda factory publication for the CB250, CL250, CB350, and CL350—not a third-party rewrite, not a scanned copy that lost half the numbers. 219 pages of the real deal.

The foreword says it plain: this manual is a guide to inspection and servicing of the Honda 250/350 models. The CL350 is used as the base for photographs, but every procedure applies across all four bikes. Codes in the manual flag differences: CB250/350 vs CL250/350. You don’t guess which carb setting belongs where. Page 16 in the Tech Data chapter lists the exact carburetor adjustments for each model. No interpretation needed.

Tech Data and Spec Tools – What You Actually Need

Section C.1 (Tech Data) and C.2 (Spec Tools) are where you start before turning a wrench. Honda lists every critical spec: valve clearance, ignition timing, compression pressure, transmission oil capacity. The special tools section names the tools you need for the eccentric rocker arm pin adjustment. You can’t set tappet clearance without that pin spanner. The manual tells you the tool number and where to get it. If you’re a home garage guy, you can improvise—but at least you know what you’re fighting.

Engine Section – The Heart of the Manual

The engine is a 4-stroke air-cooled side-by-side vertical twin with overhead cam. Honda uses a hydraulically operated cam chain tensioner. That tensioner fails if you don’t prime it after an engine rebuild. The manual covers the priming procedure in Section C.3 on engine disassembly. Engine rebuild sequence is laid out step by step: cam chain removal, cylinder head torque pattern, piston ring fitting. The torque values are in inch-pounds for small fasteners and foot-pounds for head bolts. Don’t trust a generic table. These numbers are specific to the CB/CL 250-350 castings.

7 Systems Covered – Wiring and Electrical Diagnostics

Section C.5 Electrical and C.7 Wiring Diag are gold. Honda’s ignition system uses points and condensers on these models. The manual shows you the timing marks, dwell angle specs, and the test procedure for the ignition coil. The wiring diagram in section 7 is a full schematic with color codes. I’ve chased more shorts on old Hondas than I care to count. Having the factory diagram means you trace the wire back to the main switch, not guess. If you’re working on a CL350 that’s been chopped, the Wiring diagram saves you from burning out the rectifier. There’s also an SL350 supplement at the end—same engine family, different frame and electrical routing.

Does This Manual Cover the Frame and Suspension?

Yes, Section C.4 Frame includes steering head bearing preload, swingarm pivot torque, and fork disassembly. The CL models have a different frame from the CB—the manual flags those differences using the codes (CL250/350). If you’re rebuilding the front forks, you get the oil viscosity and quantity. Not “use fork oil.” It says “ATF or SAE 10W-20, 165 cc per leg.” That level of detail prevents seal leaks and handling issues.

3 Reasons to Use OEM Documentation

First, aftermarket manuals reprint torque values that are averaged across years. Honda changed the cylinder head bolt torque for the 1971 CB350—the OEM manual has the revised spec. Second, aftermarket wiring diagrams often miscolor wires. Third, the troubleshooting flowcharts in Section C.6 Insp/Adjust come directly from Honda’s service bulletins. You get factory recalls included. I don’t trust aftermarket documentation on principle. It’s faster to open this manual than to second-guess a forum post.

FAQ

Can I use this manual to rebuild the top end of a CB350?

Yes. Section C.3 covers cylinder head removal, valve lapping, cam chain timing, and torque specs. You need the special tool for the rocker arm pin or a fabricated socket. The manual lists the tool number.

Does it include the SL350 supplement?

Yes. The supplement is 14 pages at the end covering SL350-specific frame and electrical routing. Same engine specs apply.

What torque value is listed for the CB250 flywheel nut?

Page 73 in the Tech Data section: 32–36 ft-lbs. That’s for the CB250 and CL250. The CB350 uses 40–45 ft-lbs. Always check the model code table in the foreword.

I’m a beginner with no shop experience. Will this manual help me?

It assumes you know how to use basic hand tools. But the steps are descriptive, and there are photos for every major procedure. Start with the Insp/Adjust chapter—tappet adjustment and carb sync are two good first jobs. Read the safety notes: Honda warns about engine oil hot draining and chain tensioner spring pressure.

This manual isn’t a quick read. It’s a reference you keep on the bench with greasy hands. You look up the spec, torque it once, and move on. If you’re rebuilding one of these twins—CB250, CL250, CB350, CL350—this is the only paper you need. Access the Factory Manual and keep a rag handy. You’ll spend more time working than wondering.

Related manuals you may need: Honda CB250 CB400N 1978-1984 Workshop Manual, HONDA CB/CL/SL 250/350 Shop Manual, Honda CB250, 360, CL360, CJ250T, CJ360T 1975 Workshop Manual – OEM Specs. For industry context, see Automotive Industry Overview and Manual Transmission.