Allen Bolt Kit (Upper) | Honda CB350 / CL350 / SL350

Description

Upper Allen Bolt Kit | Honda CB350 / CL350 / SL350

The factory Phillips head screws on the Honda 350 upper engine covers strip out — it’s practically inevitable. Every time you pull a cover to get at the cam, the points, or the tach drive, you risk rounding another head. This stainless steel Allen bolt kit replaces the upper engine cover fasteners with socket head cap screws that won’t strip and look clean doing it. Allen wrenches are included.

Why You Need This

Honda used Phillips head screws across the 350-series engine. They corrode, they strip, and they make routine work harder than it needs to be. Allen (socket head) bolts grip positively with an Allen wrench — no cam-out, no stripped heads, no frustration. Stainless steel resists corrosion and keeps your engine looking sharp.

This is the Upper kit — it covers the cam end holders, intake manifolds, cam box to cylinder head, points cover, tach drive cover, and tach cable. The matching Lower Allen Bolt Kit is available as a checkbox add-on and covers the side covers (left and right), chain cover, oil pump cover, and electric starter.

Specifications

Spec	Detail
Replaces OEM Parts	93500-06020-0A, 93500-06020, 93500-06050, 93500-06050-0A, 93700-05020-0B, 93700-05022-0A, 93700-06010-0B, 93700-06010-02, 93500-06016-0A, 93500-06016
Material	Stainless steel
Fits Models	CB350 K0–K5 (1968–1973), CL350 K0–K5 (1968–1973), SL350 K0–K2 (1969–1973)
Sold As	Complete upper kit with Allen wrenches

SL350 Owners: The Upper kit fits all SL350 years (K0–K2). Only the matching Lower kit splits by year — the SL350 K0 uses our Lower Allen Bolt Kit (CB350 / CL350 / SL350K0), while the SL350 K1/K2 use the Lower Allen Bolt Kit for SL350 K1/K2 (the later side covers were recast without electric start).

What’s in the Kit

• Cam end holder bolts
• Intake manifold bolts
• Cam box to cylinder head bolts
• Points cover bolts
• Tach drive cover bolts
• Tach cable bolt
• Allen wrenches

Optional Add-On (Lower Kit) Includes:

• Side cover bolts — left & right
• Chain cover bolts
• Oil pump cover bolts
• Electric starter bolts

Installation

Difficulty: Beginner

1. Remove the old Phillips screws with an impact driver — this prevents stripping the heads on removal.
2. Clean the threaded holes in the engine cases.
3. Apply anti-seize compound to the threads of the new Allen bolts.
4. Thread the bolts in by hand first, then tighten with the included Allen wrench.
5. Snug evenly and do not over-tighten — these thread into aluminum cases.

Tip: If you’re pulling covers for service, grab a CB350 Service Gasket Kit so you have fresh gaskets ready to go.

Frequently Asked Questions

Does this kit cover all the engine bolts on my CB350?

No — this is the Upper kit only. It covers the cam end holders, intake manifolds, cam box to cylinder head, points cover, tach drive cover, and tach cable. The Lower Allen Bolt Kit (available as a checkbox add-on) covers the side covers, chain cover, oil pump cover, and electric starter. To convert every exterior fastener, get both.

Does this fit my SL350 K1 or K2?

Yes — the Upper kit fits all SL350 years (K0–K2). Only the Lower kit splits by year: the SL350 K0 uses our standard Lower kit, and the SL350 K1/K2 use the SL350 K1/K2 Lower kit.

Does this fit the CB350F (four-cylinder)?

No. The CB350F is a four-cylinder with a completely different engine. This kit is for the CB350 / CL350 / SL350 twins only.

Does this fit an XL350 or another Honda model?

No. This kit is sized specifically for the CB350 / CL350 / SL350 twins. We make separate kits for the CB175 / CL175, CB200 / CL200, CB360 family, and CB450 family.

You Might Also Need

• Lower Allen Bolt Kit — CB350 / CL350 / SL350K0 — side covers, chain cover, oil pump cover, electric starter
• Carb Allen Bolt Set — CB350 / CL350 / SL350K0 — stainless replacement for the carb float bowl and diaphragm cover screws
• Lower Allen Bolt Kit — SL350 K1/K2 — the correct Lower kit if you have the later SL350
• Service Gasket Kit — CB350 / CL350 / SL350 — fresh gaskets for routine cover work
• Impact Driver Tool — the right way to remove stuck Phillips screws
• Anti-Seize Lubricant — on the threads keeps the Allen bolts from galling next time

Last updated: June 2026