Part Number	Description	Skirt	Crown Type	Ring Pack	Barrel Type
K 27	Piston K standard size for use with petrol	Full skirt	Cone	Two compression, one oil control	Iron
K 27R	Piston K  standard size 8:1 compression ratio for use with alcohol fuel	Full skirt	Cone	Two compression, one oil control	Iron
K 27/ 0	Piston K +1/2mm for use with petrol	Full skirt	Dome with valve cut outs	Three compression	Iron
K 27/ 2	Piston K 6:1 +1/2mm compression ratio				Iron
K 27/ 3	Piston K 7:1  +1/2mm compression ratio				Iron
K 27/ 4	Piston KTT MK I-III standard size 7:1  compression ratio for use with 50/50 petrol benzol mixture	Full Skirt	Dome with valve cut outs	Two compression, one oil control	Iron
K 27/ 5	Piston KTT standard size 6:1 compression ratio for petrol	Full Skirt	Dome	Two compression, one oil control	Iron
K 27/ 6	Piston KSS standard size for use with 50% petrol benzol mixture	Full Skirt	Dome with valve cut outs	Two compression, one oil control	Iron
K 27/ 6/0	Piston KSS +1/2mm for use with 50% petrol benzol mixture +1/2mm	Full Skirt	Dome with valve cut outs	Two compression, one oil control	Iron
K 27/ 7	Piston KTT MKI-III 8.5:1 standard size compression ratio for use with Discol PMS2	Full Skirt	Dome with valve cut outs	Two compression	Iron
K 27/ 8	Piston KTT MKI-III standard size 10.25:1 compression ratio for use with Discol RD1	Full Skirt	Dome with valve cut outs	Two compression	Iron
K 27/10	Piston K from KSS3800 standard size	Slipper	Dome with valve cut outs	Two compression, one oil control	Iron
K 27/10/0	Piston K from KSS3800  +1/2mm	Slipper	Dome with valve cut outs	Two compression, one oil control	Iron
K 27/11	Piston K 8.75:1 standard size for use with alcohol from KSS3800	Slipper	Dome with valve cut outs	Two compression, one oil control	Iron
K 27/12	Piston KTT400-on standard size for use with 50/50 petrol benzol mixture	Slipper	Dome with valve cut outs	Three compression	Iron
K 27/13	Piston KTT400-on standard size for use with Alcohol Fuel	Slipper	Dome with valve cut outs	Three compression	Iron
K 27/14	Piston KSS Ring Below Pin standard size to engine number KSS7475. 6.8:1 compression ratio. Replaced by K27/17	Full Skirt, ring below pin	Dome with valve cut outs	Two compression, two bevel oil control	Alloy
K 27/14/0	Piston KSS  Ring Below Pin +1/2mm to engine number KSS7475. 6.8:1 compression ratio. Replaced by K27/17/0	Full Skirt, ring below pin	Dome with valve cut outs	Two compression, two bevel oil control	Alloy
K 27/15	Piston KTT MK VI,Vll,Vlll standard size	Slipper	Dome with valve cut outs	Two compression, one slotted control	Alloy
K 27/16	Piston KTT MK Vl,Vll,Vlll standard size	Slipper	Dome with valve cut outs	Two compression, one slotted control	Alloy
K 27/17	Piston KSS MKII standard size slipper type used from KSS 7476. 7.5:1 compression ratio, 8.4:1 with compression plates removed	Slipper	Dome with valve cut outs	Two compression, one slotted control	Alloy
K 27/17/0	Piston KSS  MK II +1/2mm slipper type used from KSS 7476. 7.5:1 compression ratio, 8.4:1 with compression plates removed	Slipper	Dome with valve cut outs	Two compression, one slotted control	Alloy
K 27/17/1	Piston KSS MKII +1mm slipper type used from KSS 7476. 7.5:1 compression ratio 8.4:1 with compression plates removed	Slipper	Dome with valve cut outs	Two compression, one slotted control	Alloy
K 27/26	Piston K standard size 7:1  compression ratio	Slipper	Dome with valve cut outs
X8	PistonKTT MK1-III standard size 12:1 compression ratio for RD1 or methanol	Slipper	Dome with valve cut outs	Three compression	Iron
M 27	Piston MOV, MAC  standard size, 6 to  6.75:1 compression ratio depending on compression plates fitted in year	Slipper	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/  AS/WS	Piston MAF  standard size complete with W.S. ring				Iron
M 27/ 0	Piston MOV, MAC + 0.020" 6 to  6.75:1 compression ratio depending on compression plates fitted in year	Slipper	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/0AS/WS	Piston MAF  +1/2mm. complete with W.S. ring				Iron
M 27/1	Piston MOV, MAC  + 0.040" 6 to  6.75:1 compression ratio depending on compression plates fitted in year	Slipper	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/1AS/WS	Piston MAF  +1mm. complete with W.S. ring				Iron
M 27/ 2	Piston Iron MSS standard size, ring below pin stepped oil ring used up to MSS 3689 replaced by M27/3 with SL3/23 (slotted oil control ring) 6 to  6.4:1 compression ratio depending on commpresiion plates used	Full skirt, ring below pin	Slight dome	Two compression, two stepped oil control	Iron
M 27/2/0	Piston Iron MSS  + 0.20" ring below pin stepped oil ring used up to MSS 3689 ring replaced by M27/3/0 with SL3/41(slotted oil control ring) 6 to  6.4:1 compression ratio depending on commpresiion plates used	Full skirt, ring below pin	Slight dome	Two compression, two stepped oil control	Iron
M 27/3	Piston Iron MSS  standard size, ring below pin std, slotted oil control ring 6 to  6.4:1 compression ratio depending on commpresiion plates used	Full skirt, ring below pin	Slight dome	Two compression, one slotted oil control, one stepped oil control	Iron
M 27/3/0	Piston Iron MSS  +.020"  ring below pin std, slotted oil control ring 6 to  6.4:1 compression ratio depending on commpresiion plates used	Full skirt, ring below pin	Slight dome	Two compression, one slotted oil control, one stepped oil control	Iron
M 27/3/1	Piston Iron MSS  +.040" ring below pin std, slotted oil control ring 6 to  6.4:1 compression ratio depending on commpresiion plates used	Full skirt, ring below pin	Slight dome	Two compression, one slotted oil control, one stepped oil control	Iron
M 27/4	Piston Alloy MAC  standard size, 6.75:1 compression ratio, split skirt slipper piston	Split skirt slipper	Dome with valve cut outs	Two compression, one oil control	Alloy
M 27/5	Piston Alloy MAC +.020" , 6.75:1 compression ratio, split skirt slipper piston	Split skirt slipper	Dome with valve cut outs	Two compression, one oil control	Alloy
M 27/6	Piston Alloy MAC +.040" , 6.75:1 compression ratio, split skirt slipper piston	Split skirt slipper	Dome with valve cut outs	Two compression, one oil control	Alloy
M 27/7	Piston Alloy  MAC +.060" , 6.75:1 compression ratio, split skirt slipper piston	Split skirt slipper	Dome with valve cut outs	Two compression, one oil control	Alloy
M 27/9	Piston Alloy MSS   standard size, 6.8:1 compression ratio, split skirt for Alfin barrel	Full split skirt	Slight dome with valve cut outs	Two compression, one oil control	Alloy
M 27/10	Piston Alloy MSS +.020", 6.8:1 compression ratio, split skirt for Alfin barrel	Full split skirt	Slight dome with valve cut outs	Two compression, one oil control	Alloy
M 27/11	Piston Alloy MSS +.040", 6.8:1 compression ratio, split skirt for Alfin barrel	Full split skirt	Slight dome with valve cut outs	Two compression, one oil control	Alloy
M 27/13	Piston Viper standard size, 8.5:1 compression ratio, split skirt piston Alfin barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Alloy
M 27/14	Piston Venom  Standard size, 8:1 compression ratio, split skirt piston for Alfin barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Alloy
M 27/17	Piston Viper, Scrambler Standard size 9.3:1 compression ratio, solid skirt for iron barrel	Full skirt	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/18	Piston Viper +.020" 8.5:1 compression ratio, split skirt piston Alfin barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Alloy
M 27/19	Piston Viper +.040" 8.5:1 compression ratio, split skirt piston Alfin barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Alloy
M 27/20	Piston Venom +.020"  8:1 compression ratio, split skirt piston Alfin barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Alloy
M 27/21	Piston Venom +.040"  8:1 compression ratio, split skirt piston Alfin barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Alloy
M 27/22	Piston Viper, Scrambler +.020" 9.3:1 compression ratio, for iron barrel	Full skirt	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/23	Piston   Viper, Scrambler +.040" 9.3:1 compression ratio, for iron barrel	Full skirt	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/24	Piston Viper, Scrambler standard size 9.3:1 compression ratio, solid skirt for iron barrel	Full skirt	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/25	Piston Viper, Scrambler +.020" 9.3:1 compression ratio, solid skirt for iron barrel	Full skirt	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/26	Piston Viper, Scrambler +.040" 9.3:1 compression ratio, solid skirt for iron barrel	Full skirt	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/27	Piston Viper, Standard size, 9.3:1 compression ratio, split skirt for iron barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/28	Piston Viper, Scrambler +.020" 9.3:1 compression ratio, split skirt for iron barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/29	Piston Viper, Scrambler +.040" 9.3:1 compression ratio, split skirt for iron barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/30	Piston Alloy MSS   standard size, 6.8:1 compression ratio, split skirt for iron barrel	Full split skirt	Slight dome with valve cut outs	Two compression, one oil control	Iron
M 27/31	Piston Alloy MSS +.020", 6.8:1 compression ratio, split skirt for iron barrel	Full split skirt	Slight dome with valve cut outs	Two compression, one oil control	Iron
M 27/32	Piston Alloy MSS +.040", 6.8:1 compression ratio, split skirt for iron barrel	Full split skirt	Slight dome with valve cut outs	Two compression, one oil control	Iron
M 27/33	Piston Venom  standard size, 8:1 compression ratio, split skirt piston for iron barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/34	Piston Venom  +.020", 8:1 compression ratio, split skirt piston for iron barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Iron
M 27/35	Piston Venom  +.040", 8:1 compression ratio, split skirt piston for iron barrel	Full split skirt	Dome with valve cut outs	Two compression, one oil control	Iron
MAS 97	Piston, complete. MSS Standard size, for Alfin barrel
MAS 97/2	Piston, complete. MSS +.020", for Alfin barrel
MAS 97/3	Piston, complete. MSS +.040", Alfin barrel
MAS 97/4	Piston, complete. 500cc Scrambler, Clubman, Standard size for Alfin barrel
MAS 97/5	Piston, complete. Viper  Standard size, for Alfin barrel
MAS 97/6	Piston, complete. Venom Standard size, for Alfin barrel
MAS 97/7	Piston, complete. 500cc Scrambler, Clubman +.020", for Alfin barrel
MAS 97/8	Piston, complete. 500cc Scrambler, Clubman +.040", for Alfin barrel
MAS 97/9	Piston complete   Viper Scrambler, Clubman Standard size  for Alfin barrel
MAS 97/10	Piston, complete. Viper +.020", for Alfin barrel
MAS 97/11	Piston, complete. Viper +.040", for Alfin barrel
MAS 97/12	Piston, complete. Venom +020", for Alfin barrel
MAS 97/13	Piston, complete. Venom +.040", for Alfin barrel
MAS 97/14	Piston, complete   Viper Scrambler, Clubman +020"  for Alfin barrel
MAS 97/15	Piston, complete   Viper Scrambler, Clubman +.040" for Alfin barrel
MAS 97/16	Piston, complete   Viper Scrambler, Clubman Standard size  for iron barrel
MAS 97/17	Piston, complete   Viper Scrambler, Clubman +.020" for iron barrel
MAS 97/18	Piston, complete   Viper Scrambler, Clubman +.040" for iron barrel
MAS 97/19	Piston, complete. Viper standard size for iron barrel
MAS 97/20	Piston, complete. Viper +.020" for iron barrel
MAS 97/21	Piston, complete. Viper +.040" for iron barrel
MAS 97/22	Piston, complete. MSS Standard size for iron barrel
MAS 97/23	Piston, complete. MSS +.020" for iron barrel
MAS 97/24	Piston, complete. MSS +.040" for iron barrel
MAS 97/25	Piston, complete. Venom standard size for iron barrel
MAS 97/26	Piston, complete. Venom +.020" for iron barrel for iron barrel
MAS 97/27	Piston, complete. Venom +.040" for iron barrel for iron barrel
MAS 97/28	Piston, complete. Scrambler, Clubman, Thruxton, Endurance  standard size for iron barrel
MAS 97/29	Piston, complete. Scrambler, Clubman, Thruxton, Endurance   +.020" for iron barrel
MAS 97/30	Piston, complete. Scrambler, Clubman, Thruxton, Endurance   +.040" for iron barrel
T2/2	Piston, cast iron U, USS, 32
RT 27 U	Piston, aluminium U, USS, 32	Two Stroke	Deflector	Two compression	Iron
RT 27/2	Piston 1930 GTP standard size	Two Stroke	Deflector	Two compression	Iron
RT 27/2/0	Piston 1930 GTP +1/2mm	Two Stroke	Deflector	Two compression	Iron
RT 27/3	Piston GTP standard size	Two Stroke	Deflector	Two compression	Iron
RT 27/3/0	Piston GTP +1/2 mm	Two Stroke	Deflector	Two compression	Iron
RT 27/3/1	Piston GTP +1 mm	Two Stroke	Deflector	Two compression	Iron