CMS-Japanese Motorcycle Supply Parts

Honda CX500, GL500, CX650, GL650 Oil Seal and O-ring list

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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 USeBay CAeBay UKeBay AU
One required
Gear shift shaft oil seal 14x26x6 91251‑ZW5‑003
(eBay USeBay CAeBay UKeBay AU)
One required
Clutch shaft oil seal 12x18x3 91201‑951‑003 One required
Tacho drive seal 6x14.5x5 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 14x2.5 14x2.5 91301‑268‑020
(eBay USeBay CAeBay UKeBay 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 6.5x3.1 6x3mm 91312‑415‑000
(eBay USeBay CAeBay UKeBay AU)
CX/GL500s with manual tensioner setup only
Oil orifice - between block and head 6.9x1.5 6.5x1.5 91302‑044‑013
(eBay USeBay CAeBay UKeBay AU)
2 **Viton recommended. See note below.
Oil filter to front cover 81x4.5 81x4.5 or 80x4.5 91311‑415‑000
(eBay USeBay CAeBay UKeBay AU)
Oil filter bolt 15x2.5 15x2.5 91302‑377‑000
(eBay USeBay CAeBay UKeBay AU)
1 Viton recommended
Oil pump pickup arm to pump body - early style
(CDI typically)
11.8x2.4 11.8x2.4 16997‑357‑003
(eBay USeBay CAeBay UKeBay AU)
1 Viton recommended
Oil pump pickup arm to pump body - later style
(TI typically, some '81 CDI?)
15x2.5 15x2.5 91302‑377‑000
(eBay USeBay CAeBay UKeBay AU)
1 Viton recommended
Starter motor 24.4x3.1 24.4x3.1 91309‑300‑000
(eBay USeBay CAeBay UKeBay AU)
Where it fits into the rear cover
Starter motor body 60x1.4 60x1.4 31206‑415‑000
1 So it's not oil related but it's with the other starter O-ring...
Dipstick O-ring 21.5x3.2 22x3 91301‑250‑000
1 Consider Viton. Superseded part no. is 22x3.
Up to serial #2000256 use 94608‑50000
Oil orifice to gearbox holder 8x2 8x2 91303‑001‑000
1 Consider Viton. 500 and 650 are the same
Inspection covers 27.5mm 91302‑001‑000
3 One on final drive, one on front of engine, one on rear engine cover
Front cover oil transfer pipe 11.8x2.4 11.8x2.4 16997‑357‑003
2 Viton recommended
Crank plate oil jet 8.2x1.5 8.2x1.5 91308‑MC7‑000 1 Viton recommended. 650s only
Oil pickup screen to pickup arm 15.3x3.5 15.3x3.5 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 - 8.8x1.9), 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 13.5x1.4 13.5x1.6 91307‑PH7‑660 1 Originally listed as 12.5x1.4 - 91307‑611‑000
>Water pipes near thermostat +
water pump to external pipe
21.9x2.5 91302‑371‑013
5 650s need only 4, they have a separate O-ring
for the water pump to pipe
Coolant passageways under rear engine cover 23x2.8 23x2.8 94608‑50000 2
Thermostat housing 53.8x3.1 54x3 91302‑657‑000
(eBay USeBay CAeBay UKeBay AU)
1 Genuine available
Water pipe elbows to head 23x2.8 23x3 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... 127x3, 126x3 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 2.8x1.1 3x1 Part of 16016‑410‑601 kit or 16010‑415‑003 kit 2
Carb float bowl drain screw 4.2x1.3 3/16"x1/16" 2
Carb vacuum slide plug 6.9x1.3 7x1.5 16010‑415‑003 - part of kit 2 Inside vacuum slide
Carb Accelerator Pump passage 5.0x1.3 5x1.2 Part of 16010‑MA1‑671 kit? 2 At float bowl. Many models do not have an acc. pump
Carb fuel transfer tube 5.8x2 5.8x1.9 Part of 16010‑415‑003 kit 2
Accelerator pump fuel transfer tube 3.8x2 3.8x1.9 Part of 16010‑MA1‑671 kit 2
Inlet manifold - carb to head side 40x2.5 40x2.5 91325‑567‑005
2 Superseded part no. was 40x2.4

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 62.7x4 63x4 91356-415-003 1 Between final drive and rear wheel
Final drive spline 96.5x2 96x2 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 14.8x2.4 14.8x2.4 91212-422-006 1 CX500E Sports, CX650E Eurosport, Turbos
Rear monoshock upper mount 14.5x1.5 14.5x1.5 52478-MC7-003 2 CX500E Sports
Fork cap bolt, 33mm ? ? 94608-30000
(eBay USeBay CAeBay UKeBay AU)
Drive shaft, larger ID 53.6x2.4 53.6x2.4 91354-415-003 1
Drive shaft, smaller ID 49.6x3.5 49.6x3.5 91353-415-003

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