Allen Bolt Kit | Honda CT90 / Trail 90

Description

Allen Bolt Kit | Honda CT90 / Trail 90

The factory JIS screws holding your CT90 engine covers together are soft, and they strip the first time you fight one with the wrong driver. After decades of service, most Trail 90s show up with at least one rounded-out cover screw. This full stainless steel Allen bolt kit replaces the soft factory screws across the engine with socket head cap screws that won’t strip and look clean doing it. Allen wrenches are included.

Why You Need This

Honda used soft JIS cross-head screws all over the CT90 engine covers. They strip, they corrode, and they make every oil change and tune-up harder than it needs to be. Allen (socket head) bolts grip positively with an Allen wrench — no cam-out, no stripped heads. Stainless steel resists corrosion and keeps your engine looking sharp. This kit covers all the normally serviced engine sections short of a full teardown.

Specifications

Spec	Detail
Material	Stainless steel
Fits Models	CT90 / Trail 90 (1966–1979)
Sold As	Complete kit with Allen wrenches

What’s in the Kit

• Left crankcase cover bolts
• Right crankcase cover bolts
• Stator cover bolts
• Points cover bolts
• Points base cover bolts
• Low gear box cover bolts
• Camshaft cover bolts
• Oil filter cover bolts
• Allen wrenches

Not included: the screws that hold the crankcase halves together, the oil pump bolts, and the clutch basket bolts. This kit covers the bolt-on engine covers, not the internal teardown hardware.

Installation

Difficulty: Beginner

1. Remove the old JIS screws with an impact driver — this prevents stripping the heads on removal.
2. Work one cover at a time so the bolts don’t get mixed up.
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: Some covers use bolts of different lengths — the right crankcase cover, for example, takes longer bolts at the dowel-pin positions. The kit’s bolt-placement diagram shows which bolt goes where. Have fresh gaskets ready before you pull any cover.

Frequently Asked Questions

Does this kit replace every bolt on the engine?

It replaces the bolts on all the normally serviced engine covers — the left and right crankcase covers, stator cover, points and points base covers, low gear box cover, camshaft cover, and oil filter cover. It does not include the internal teardown hardware: the crankcase-half screws, oil pump bolts, and clutch basket bolts.

Are the Allen wrenches included?

Yes — the kit comes with the Allen wrenches you need to install the new hardware.

Why switch from the factory screws?

The factory JIS screws are soft and strip easily, especially after decades of service with the wrong driver. Stainless Allen bolts grip positively, won’t cam out, and resist corrosion — so the next time you pull a cover, it comes apart clean.

You Might Also Need

• Ignition Points & Timing Plate Screw Set — CT90 — the matching stainless Allen set for the points and timing plate
• Impact Driver Tool — the right way to remove stuck JIS screws
• Anti-Seize Lubricant — on the threads keeps the Allen bolts from galling next time

Last updated: June 2026