Any omissions or errors please use the contact form to let me know! There’s still some to add…
These tables are sortable if you click on the heading in each table.
The "Available Size" column are sizes which have been found to work and may be easier to source from a non-genuine O-ring supplier than the genuine sizes.
Shaft seal List – Honda CX500, GL500, CX650, GL650
Shaft seals sizes have three measurements; inside, outside and width.
Seal | Size | Honda Part No. | Notes |
---|---|---|---|
Camshaft rear oil seal | 18x28x6 | 91202‑283‑013 (eBay US, eBay CA, eBay UK, eBay AU |
One required |
Gear shift shaft oil seal | 14x26x6 | 91251‑ZW5‑003 (eBay US, eBay CA, eBay UK, eBay AU) |
One required |
Clutch shaft oil seal | 12x18x3 | 91201‑951‑003 | One required |
Tacho drive seal | 6×14.5×5 | 91211‑415‑003 | One required |
Rear shock seal, CX500E Sports | ? | 91257‑MC7‑003 | One required |
Rear shock seal, GL500 and GL500I | ? | 91257‑MA2‑003 | One required |
Oil-related O-rings List – Honda CX500, GL500, CX650, GL650
O-ring | Size | Available size | Honda Part No. | No. Req’d | Notes |
---|---|---|---|---|---|
Block oil passageways – see notes | 14×2.5 | 14×2.5 | 91301‑268‑020 (eBay US, eBay CA, eBay UK, eBay AU) |
4 | This covers: Oil pump to front cover Front cover to block Block to crank support plate Camshaft holder O-ring |
Manual cam chain tensioner bolt | 6.5×3.1 | 6x3mm | 91312‑415‑000 (eBay US, eBay CA, eBay UK, eBay AU) |
CX/GL500s with manual tensioner setup only | |
Oil orifice – between block and head | 6.9×1.5 | 6.5×1.5 | 91302‑044‑013 (eBay US, eBay CA, eBay UK, eBay AU) |
2 | **Viton recommended. See note below. |
Oil filter to front cover | 81×4.5 | 81×4.5 or 80×4.5 | 91311‑415‑000 91315‑MA6‑003 (eBay US, eBay CA, eBay UK, eBay AU) |
1 | |
Oil filter bolt | 15×2.5 | 15×2.5 | 91302‑377‑000 (eBay US, eBay CA, eBay UK, eBay AU) |
1 | Viton recommended |
Oil pump pickup arm to pump body – early style (CDI typically) |
11.8×2.4 | 11.8×2.4 | 16997‑357‑003 91320‑HA5‑000 91320‑HA5‑003 91302‑ZE9‑000 91302‑ZE9‑003 91320‑MJ6‑003 (eBay US, eBay CA, eBay UK, eBay AU) |
1 | Viton recommended |
Oil pump pickup arm to pump body – later style (TI typically, some ’81 CDI?) |
15×2.5 | 15×2.5 | 91302‑377‑000 (eBay US, eBay CA, eBay UK, eBay AU) |
1 | Viton recommended |
Starter motor | 24.4×3.1 | 24.4×3.1 | 91309‑300‑000 91309‑425‑003 (eBay US, eBay CA, eBay UK, eBay AU) |
Where it fits into the rear cover | |
Starter motor body | 60×1.4 | 60x 1.4 |
31206‑415‑000 31206‑402‑008 |
1 | So it’s not oil related but it’s with the other starter O-ring… |
Dipstick O-ring | 21.5×3.2 | 22×3 | 91301‑250‑000 91307‑425‑003 |
1 | Consider Viton. Superseded part no. is 22×3. Up to serial #2000256 use 94608‑50000 (23×2.8) |
Oil orifice to gearbox holder | 8×2 | 8×2 | 91303‑001‑000 91306‑HB3‑003 |
1 | Consider Viton. 500 and 650 are the same |
Inspection covers | 27.5mm | 91302‑001‑000 91302‑001‑710 |
3 | One on final drive, one on front of engine, one on rear engine cover | |
Front cover oil transfer pipe | 11.8×2.4 | 11.8×2.4 | 16997‑357‑003 91320‑HA5‑003 91302‑ZE9‑000 91302‑ZE9‑003 91320‑MJ6‑003 |
2 | Viton recommended |
Crank plate oil jet | 8.2×1.5 | 8.2×1.5 | 91308‑MC7‑000 | 1 | Viton recommended. 650s only |
Oil pickup screen to pickup arm | 15.3×3.5 | 15.3×3.5 | 91363‑MC7‑004 | 1 | Viton recommended. 650s only |
**Honda’s part no. in the fiches appears incorrect here (91302-044-003, 91302-044-003 – 8.7x 1.8, 91302-GE0-000 – 8.8×1.9), correct is above.
Coolant-related O-rings List – Honda CX500, GL500, CX650, GL650
O-ring | Size | Available size | Honda Part No. | No. Req’d | Notes |
---|---|---|---|---|---|
Coolant Temp Sender O-ring | 13.5×1.4 | 13.5×1.6 | 91307‑PH7‑660 | 1 | Originally listed as 12.5×1.4 – 91307‑611‑000 |
>Water pipes near thermostat + water pump to external pipe |
21.9×2.5 | 91302‑371‑013 91302‑371‑023 91301‑MB6‑003 |
5 | 650s need only 4, they have a separate O-ring for the water pump to pipe |
|
Coolant passageways under rear engine cover | 23×2.8 | 23×2.8 | 94608‑50000 | 2 | |
Thermostat housing | 53.8×3.1 | 54×3 | 91302‑657‑000 (eBay US, eBay CA, eBay UK, eBay AU) |
1 | Genuine available |
Water pipe elbows to head | 23×2.8 | 23×3 | 94608‑50000 | 2 | |
Metal water pipe to water pump housing – 650s | "Seal" | – | 91302‑415‑003 | 1 | Not an O-ring in shape. No idea why it has a 415 product code… |
Water pump cover O-ring | Saturn-shaped… | 127×3, 126×3 | 11396‑415‑000 | 1 | Regular O-ring conforms to fit just fine in the above sizes |
Carb-related O-rings – Honda CX500, GL500, CX650, GL650
O-ring | Size | Available size | Honda Part No. | No. Req’d | Notes |
---|---|---|---|---|---|
Carb idle mixture screw | 2.8×1.1 | 3×1 | Part of 16016‑410‑601 kit or 16010‑415‑003 kit | 2 | |
Carb float bowl drain screw | 4.2×1.3 | 3/16"x1/16" | 2 | ||
Carb vacuum slide plug | 6.9×1.3 | 7×1.5 | 16010‑415‑003 – part of kit | 2 | Inside vacuum slide |
Carb Accelerator Pump passage | 5.0×1.3 | 5×1.2 | Part of 16010‑MA1‑671 kit? | 2 | At float bowl. Many models do not have an acc. pump |
Carb fuel transfer tube | 5.8×2 | 5.8×1.9 | Part of 16010‑415‑003 kit | 2 | |
Accelerator pump fuel transfer tube | 3.8×2 | 3.8×1.9 | Part of 16010‑MA1‑671 kit | 2 | |
Inlet manifold – carb to head side | 40×2.5 | 40×2.5 | 91325‑567‑005 91325‑413‑830 |
2 | Superseded part no. was 40×2.4 |
Chassis, Brake and Misc O-ring List – Honda CX500, GL500, CX650, GL650
O-ring | Size | Available size | Honda Part No. | No. Req’d | Notes |
---|---|---|---|---|---|
Final drive spline | 62.7×4 | 63×4 | 91356-415-003 | 1 | Between final drive and rear wheel |
Final drive spline | 96.5×2 | 96×2 | 91355-371-003 | 1 | Rear wheel |
Final drive spline | In the final drive | ||||
Fuel tank level sender | 1 | Sports and Eurosports, also Turbos? | |||
Rear brake master cylinder | 14.8×2.4 | 14.8×2.4 | 91212-422-006 | 1 | CX500E Sports, CX650E Eurosport, Turbos |
Rear monoshock upper mount | 14.5×1.5 | 14.5×1.5 | 52478-MC7-003 | 2 | CX500E Sports |
Fork cap bolt, 33mm | ? | ? | 94608-30000 (eBay US, eBay CA, eBay UK, eBay AU) |
2 | |
Drive shaft, larger ID | 53.6×2.4 | 53.6×2.4 | 91354-415-003 | 1 | |
Drive shaft, smaller ID | 49.6×3.5 | 49.6×3.5 | 91353-415-003 91353-415-004 |
1 |