D. Gas Valve Inner Seal Disks


OMG 12x1 left front view

OMG front

OMG 12x1 L back

OMG rear

Inner Seal Discs

These rubber disks are hard and deteriorated after 30 years. The rest of the petcock is metal and lasts forever, or has round seal rings that are relatively easy to find.

Cross Referencing Hopes: The sizes, applications, and possible sourcing of these vital rubber disks is being studied. It is hoped that some of the common moped gas valves might use the same rubber seal as some kinds of Honda, Kawasaki, Suzuki, Yamaha, or others. When that information becomes available, it will be posted here. Then anyone could order a seal disk for a small brand name bike from a big brand name parts supplier. 

Flipping: Old rubber inner seal disks get hard, shrink, and become deformed. Some can be flipped over to expose a fresh unused side.

Karkoma 16x1 spigot back with decomposed urethane disk

Karkoma 16×1 spigot back with decomposed disk

Vintage Karcoma: Left, an actual original 1970’s Karkoma (Germany) gas valve from a 1979 Kynast moped, with only 50 miles of use. 30+ years of sitting with old, rotten gasoline premix has completely clogged the passageways with hard tar, and decomposed the seal disk to where it broke when the valve was disassembled. Part of the seal disk shaped like a smile broke off and stuck to the movable plate with handle. Usually when these get sticky the handle ends up getting snapped off, in addition to the seal disk crumbling and the holes clogged.  This is the kind that uses a 3.3mm tall lip on the outer edge of the 2.0mm tall by 13.7mm diameter seal disk D4. Later 1980’s Karkoma valves did not have the lip. For those the D4 early seal disk lip must be carefully ground off. Even the last few new old stock 1970’s Karkoma seal disks, once clear orange, now cloudy gold, are brittle and crack and crumble easily in your fingers. Too bad. That is why disk D4 is N/A not available.





Seal disks D1 to D6

Seal disk D8

OMG seal disk 13.9 x 1.6 3 rings stick up from holes they fit inside valve holes

D9 OMG seal disk 13.9 x 1.6
3 rings stick up from holes
they fit inside valve holes
to keep disk from rotating










 #  price  OD x thickness  style   Fuel Petcock Inner Seal Disks
N/A    19.3 x 3.0  8 holes Honda 16115-001-004 60’s Cub
D2x $$8   16.3 x 3.0  4 holes Honda 16957-ZE1-812 replaces 16955-011-010, 16955-028-004
D2x $00   16.3 x  3.0 4 holes fits 60’s-70’s Honda’s and Trac Eagle (Korea), Angel (Taiwan)
D2a N/A    15.8 x 2.8  4 holes very shrunk D2 from ’65 Honda CA200
D2b N/A    16.2 x 2.8  4 holes shrunk D2
D2c $22   16.3 x 3.0  4 holes D2 with the 4 holes widened
D3x $$7   22.0 x 2.3  2+2 holes Piaggio 013836 vintage Vespa scooters
D4x N/A    13.7 x 2.0  3.3 outer lip, 70’s Karkoma (Germany)
D5x N/A    14.0 x 2.0  3 ∅3.5 holes 70’s Paioli for valve A33
D5a N/A    14.9 x 3.2  3 holes shrunk unknown
D6a N/A    13.4 x 2.3  3 holes shrunk aftermarket
D7x N/A    13.7 x 2.0  3 holes no outer lip, 80’s Karkoma (Germany)
D8x $12   18.8 x 3.1  3 holes blue Derbi (Spain) valve=18.5
D8a $$5   18.6 x 3.0  3 holes shrunk D8
D9x $13   13.9 x 1.6  3 holes 3 lips OMG (Italy) for most replacements
D10 $$9   20.4 x 3.3  4 holes Honda 16955-268-020 another view
 $$$   20.5 x 3.2  4 holes Indian (Taiwan) for valve A35
D11 N/A    22.3 x 3.5  4 holes General (Taiwan) for valve A28
D16 N/A    28.5 x 2.4  5 holes KL-18-6643 Kawasaki 11009-1194
D17 N/A    22.6 x 2.4  5 holes KL-18-6644 Kawasaki 11009-1188
D18 N/A    23.0 x 2.4  2 holes + slot KL-18-6645 Kawasaki 43049-1066
D19 N/A    18.8 x 2.4  4 holes KL-18-6646 Kawasaki 43049-1017
D21 N/A    00.0 x 0.0  Honda 17993
D22 N/A    00.0 x 0.0  Honda 16955-HA2-005  close up view
D24 N/A    00.0 x 0.0  Kawasaki 92065-094
D25 N/A    00.0 x 0.0  Kawasaki 92065-055
D26 N/A    00.0 x 0.0  Suzuki 44341-18450
D27 N/A    00.0 x 0.0  Suzuki 51455-010
D28 N/A    00.0 x 0.0  Yamaha 47X-24523-00
D29 N/A    00.0 x 0.0  Yamaha 137-24523-00

KL Supply seal disks scaled

Seal disks D16 to D19:
These four KL Supply petcock inner seal disks have dozens of motorcycle and ATV applications, and hopefully some mopeds.

Valve A33 with disk D5

D5 seal disk