More power, less talking

Performance that simply works. Whether you're looking for a replacement for a production part or a solid tuning upgrade, GPO cylinders deliver exactly what you need: clean workmanship, reliable fit, and honest performance. No unnecessary bells and whistles, no marketing jargon. Just parts that work—for everyone who prefers to tinker and ride instead of talking big.

Set

Hot

GPO Ø 41 mm "Sombrero" cylinder kit | Puch X30 Velux, NG-2AH

For: Puch

34863

GPO Ø 41 mm "Sombrero" cylinder kit | Puch X30 Velux, NG-2AH

Manufacturer: GPO · Material: Gray cast iron · Area of application: Tuning · Displacement: 57 ccm · Crankshaft stroke: 43 mm · Ø piston pin (B): 10 mm · Ø piston pin (B): 12 mm · Number of fixing points: 4 pcs · Nominal diameter: 41 mm · Ø cylinder neck: 44.7 mm · Ø outlet inside: 25 mm · Ø Inlet inside: 19 mm · Thread inlet: M6x1 (standard thread) · Hole spacing inlet: 32 mm · Outlet type: straight · Hole spacing outlet: 42 mm · Thread outlet: M6x1 (standard thread) · Hole pattern [mm]: 44 x 44 · Decompressor: No · Camouflaged: No

EUR 245.20

Set

Hot

GPO 43 mm "Pomodoro" cylinder kit | Sachs 503

For: Sachs

34470

GPO 43 mm "Pomodoro" cylinder kit | Sachs 503

Nominal diameter: 43 mm · Manufacturer: GPO · Material: Gray cast iron · Displacement: 63 ccm · Crankshaft stroke: 43 mm · Ø cylinder neck: 45 mm · Ø Outlet outside: 26 mm · Ø outlet inside: 22 mm · Ø Inlet inside: 19 mm · Thread inlet: M6x1 (standard thread) · Hole spacing inlet: 32 mm · Ø piston pin (B): 12 mm · Outlet type: clamped · Hole pattern [mm]: 40 x 60 / 37 x 37 · Area of application: Tuning

EUR 275.80

GPO 41 mm cylinder | Sachs 50/3, 50/4 (square inlet) fan-cooled (DE)

For: Sachs

25623

GPO 41 mm cylinder | Sachs 50/3, 50/4 (square inlet) fan-cooled (DE)

Nominal diameter: 41 mm · Manufacturer: GPO · Material: Gray cast iron · Surface: raw · Area of application: Tuning · Displacement: 55 ccm · Crankshaft stroke: 42 mm · Ø Outlet outside: 40 mm · Hole spacing inlet: 31 mm · Number of fixing points: 4 pcs · Outlet type: Union nut · Cooling type: Fan air cooling

EUR 120.10

GPO 44 mm cylinder kit tuning 12 mm KoBo | Tomos A35

For: Tomos

19803

GPO 44 mm cylinder kit tuning 12 mm KoBo | Tomos A35

Manufacturer: GPO · Material: Aluminum · Camouflaged: No · Surface: sandblasted · Crankshaft stroke: 43 mm · Displacement: 65 ccm · Nominal diameter: 44 mm · Ø cylinder neck: 47.8 mm · Area of application: Tuning · Hole spacing inlet: 36 mm · Hole spacing inlet: 39 mm · Number of fixing points: 4 pcs · Ø piston pin (B): 12 mm · Inlet window: 35.5 x 29.5 · Thread inlet: M5x0.8 (standard thread) · Ø outlet inside: 22.8 mm · Hole spacing outlet: 42 mm · Hole pattern [mm]: 44 x 44 · Outlet type: slanted · Thread outlet: M6x1 (standard thread) · Decompressor: No

EUR 110.30

For: Puch

19545

GPO 45 mm cylinder kit 70 ccm | Puch

Manufacturer: GPO · Material: Aluminum · Camouflaged: No · Surface: sandblasted · Displacement: 70 ccm · Crankshaft stroke: 43 mm · Ø piston pin (B): 12 mm · Nominal diameter: 45 mm · Ø cylinder neck: 47.8 mm · Ø outlet inside: 23.4 mm · Area of application: Tuning · Inlet window: 21.4 x 13.5 · Thread inlet: M6x1 (standard thread) · Hole spacing outlet: 42 mm · Outlet type: straight · Thread outlet: M6x1 (standard thread) · Number of fixing points: 4 pcs · Hole pattern [mm]: 44 x 44 · Decompressor: No · Hole spacing inlet: 38 mm

EUR 122.50

Set

GPO 41 mm cylinder kit fan-cooled diaphragm | Sachs 50/2, 50/3, 50/4 (DE)

For: Sachs

27618

GPO 41 mm cylinder kit fan-cooled diaphragm | Sachs 50/2, 50/3, 50/4 (DE)

Nominal diameter: 41 mm · Manufacturer: GPO · Material: Gray cast iron · Surface: sandblasted · Displacement: 55 ccm · Crankshaft stroke: 42 mm · Thread inlet: M5x0.8 (standard thread) · Hole spacing inlet: 67 mm · Ø piston pin (B): 12 mm · Outlet type: Union nut · Thread outlet: M35x2 (standard thread) · Number of fixing points: 4 pcs · Hole pattern [mm]: 51 x 40 · Camouflaged: No · Area of application: Tuning

EUR 187.50

Set

GPO 38 mm original cylinder fan-cooled 12 mm KoBo | Velux/NG-2AH

For: Puch

21175

GPO 38 mm original cylinder fan-cooled 12 mm KoBo | Velux/NG-2AH

Nominal diameter: 38 mm · Manufacturer: GPO · Material: Gray cast iron · Area of application: Standard · Surface: sandblasted · Displacement: 50 ccm · Crankshaft stroke: 43 mm · Thread inlet: M6x1 (standard thread) · Hole spacing inlet: 32 mm · Ø piston pin (B): 12 mm · Outlet type: straight · Hole spacing outlet: 42 mm · Thread outlet: M6x1 (standard thread) · Number of fixing points: 4 pcs · Hole pattern [mm]: 44 x 44 · Camouflaged: No

EUR 153.20

GPO 41 mm "Sombrero" cylinder kit | Puch M50, MS50, VS50, DS50, VZ50

For: Puch

37468

GPO 41 mm "Sombrero" cylinder kit | Puch M50, MS50, VS50, DS50, VZ50

Nominal diameter: 41 mm · Manufacturer: GPO · Material: Gray cast iron · Displacement: 57 ccm · Crankshaft stroke: 43 mm · Ø cylinder neck: 43 mm · Ø outlet inside: 25 mm · Ø Inlet inside: 19 mm · Thread inlet: M6x1 (standard thread) · Hole spacing inlet: 42 mm · Ø piston pin (B): 10 mm · Ø piston pin (B): 12 mm · Outlet type: straight · Hole spacing outlet: 42 mm · Thread outlet: M6x1 (standard thread) · Number of fixing points: 4 pcs · Hole pattern [mm]: 44 x 44 · Decompressor: No · Camouflaged: No · Area of application: Tuning

EUR 245.20

For: Solex

15210

GPO 40 mm cylinder kit | Solex

Manufacturer: GPO · Camouflaged: No · Material: Aluminum · Surface: sandblasted · Nominal diameter: 40 mm · Ø outlet inside: 15 mm · Ø Inlet inside: 10 mm · Hole spacing inlet: 32.5 mm · Ø piston pin (B): 12 mm · Hole spacing outlet: 32.5 mm · Thread inlet: M6x1 (standard thread) · Hole pattern [mm]: 41.5 · Area of application: Tuning · Number of fixing points: 4 pcs · Outlet type: straight · Thread outlet: M6x1 (standard thread) · Decompressor: Yes

EUR 133.60

Set

GPO 41 mm cylinder kit square inlet | Sachs 50/3, 50/4 LKH

For: Sachs

27620

GPO 41 mm cylinder kit square inlet | Sachs 50/3, 50/4 LKH

Nominal diameter: 41 mm · Manufacturer: GPO · Material: Gray cast iron · Surface: sandblasted · Displacement: 55 ccm · Crankshaft stroke: 42 mm · Thread inlet: M5x0.8 (standard thread) · Hole spacing inlet: 31 mm · Ø piston pin (B): 12 mm · Outlet type: Union nut · Thread outlet: MF40x1.5 (fine pitch thread) · Number of fixing points: 4 pcs · Hole pattern [mm]: 51 x 40 · Camouflaged: No · Area of application: Tuning

EUR 187.50

Retracting cylinders – how to do it correctly

Although pistons, rings, and cylinders are manufactured with precision, they do not yet fit together perfectly. During the running-in process, they slowly grind themselves into place—and this is the only way to achieve a clean fit without material breakouts. Driving at full throttle immediately after assembly can cause serious damage.

Here's how to do it correctly:

Warm up at idle speed: After starting the engine, let it idle for about 10–15 minutes. This allows the oil to distribute evenly in the cylinder.
The first few kilometers: Only use half throttle at moderate speed (max. 5000–6000 rpm); occasional speed jumps allow the contact surfaces to run in smoothly. Avoid long hill climbs or high revs during the first 100 km.
Be patient: After about an hour of running-in time (instead of the old myths of 300 km or 10 hours of running time), you can carefully move on to longer, heavier loads. Approach more load and revs cautiously.
Take breaks: Allow the engine to rest, especially after periods of stress, as friction causes thermal build-up. This protects against heat damage and warping problems.
Additional lubrication: Add 50–100 ml of extra 2-stroke oil to the first few tank fillings – this helps with smooth running-in.

Conclusion:
Only with tact and care can you achieve long-lasting and powerful performance. The right temperature, varying speed, and gentle load ensure a cleanly run-in cylinder – and real driving pleasure without consequential damage.

New

Inox

swiing® ingenious ignition cams +/- 2° | Piaggio Ciao, SI, Bravo, Boxer

For: Piaggio

36810

swiing® ingenious ignition cams +/- 2° | Piaggio Ciao, SI, Bravo, Boxer

Manufacturer: swiing® ingenious parts · Material: Chrome steel (known as Nirosta®) · Surface: electropolished · Ø inside: 14.4 mm · Total length: 10.5 mm · Alternative version of the Piaggio OEM number: 103137

EUR 24.40

New

Inox

swiing® ingenious ignition cams +/- 4° | Piaggio Ciao, SI, Bravo, Boxer

For: Piaggio

36811

swiing® ingenious ignition cams +/- 4° | Piaggio Ciao, SI, Bravo, Boxer

EUR 24.40

New

Inox

swiing® ingenious ignition cams +/- 2° Athena / Jasil crankshaft | Piaggio Ciao, SI, Bravo, Boxer

For: Piaggio

37755

swiing® ingenious ignition cams +/- 2° Athena / Jasil crankshaft | Piaggio Ciao, SI, Bravo, Boxer

Manufacturer: swiing® ingenious parts · Material: Chrome steel (known as Nirosta®) · Surface: electropolished · Ø inside: 14.4 mm · Total length: 9.5 mm · Alternative version of the Piaggio OEM number: 103137

EUR 28.10

New

Inox

swiing® ingenious ignition cams +/- 4° Athena / Jasil crankshaft | Piaggio Ciao, SI, Bravo, Boxer

For: Piaggio

37756

swiing® ingenious ignition cams +/- 4° Athena / Jasil crankshaft | Piaggio Ciao, SI, Bravo, Boxer

EUR 28.10

New

Nos

Universal

36363

CEV lamp pot Ø 130 mm black NOS

Manufacturer: CEV · Material: Sheet metal (steel) · Color: black · Surface: varnished · Total length: 70 mm · Ø outside: 130 mm · Ø External connection: 124.2 mm · Width: 132.7 mm · Thread size: M6 · Mounting type: Screws · Number of fixing points: 2 pcs · CEV OEM number: 04601 04785

EUR 122.50

New

OMG fuel filter "T" metal 8 mm (removable)

Universal

35379

OMG fuel filter "T" metal 8 mm (removable)

Manufacturer: OMG · Outer width: 52 mm · Material: Plastic · Material: Steel · Surface: galvanized (yellow) · Color: transparent · Filter type: Plastic net · demountable: Yes · Ø fuel hose connection: 8 mm · Ø outside: 22.5 mm · Ø inside: 3.8 mm · Ø inside: 4.6 mm · Total length: 58.8 mm

EUR 14.40

New

swiing® revival wheel axle set cast rim front | Hercules Prima, Optima

For: Hercules

36493

swiing® revival wheel axle set cast rim front | Hercules Prima, Optima

Manufacturer: swiing® revival parts · Material: Chrome steel (known as Nirosta®) · Material: Steel · Surface: galvanized (blue) · Thread type: MF11x1 (fine pitch thread) · Ø shaft: 11 mm · Total length: 145 mm · Thread length: 55 mm · Thread length: 65 mm · Shank length: 25 mm · Ball bearing closed: No · Ø ball [inch] / [mm]: 1/4" (6.35 mm) · Hercules OEM number: 0871 207 100

EUR 42.80

New

ASP clutch conversion kit "sheet" 3-jaw Aramid | Puch E50

For: Puch

35760

ASP clutch conversion kit "sheet" 3-jaw Aramid | Puch E50

Manufacturer: ASP · Material: Steel · Material addition: Aramid (known as Kevlar®) · Number of jaws: 3 pcs · Number of springs: 6 pcs · Thickness: 12 mm · Area of application: Racing · Area of application: Tuning

EUR 220.60

New

ASP clutch conversion kit "sheet" 2-jaw Aramid | Puch E50

For: Puch

35410

ASP clutch conversion kit "sheet" 2-jaw Aramid | Puch E50

Manufacturer: ASP · Material: Steel · Material addition: Aramid (known as Kevlar®) · Number of jaws: 2 pcs · Number of springs: 4 pcs · Thickness: 12 mm · Area of application: Racing · Area of application: Tuning

EUR 153.20

New

Set

Air filter set swiing® ingenious SRF 17 mm | Puch X30 NS, NL

For: Puch

37793

Air filter set swiing® ingenious SRF 17 mm | Puch X30 NS, NL

Manufacturer: Made in Switzerland · Color: black · Material: Plastic · Filter type: Racing screen · Filter type: Standard sieve · Total length: 350 mm · Ø Internal connection: 27 mm · Mounting type: Plug connection clamped · Mounting type: Tab for screwing · Area of application: Racing · Area of application: Tuning · Puch OEM number: 321.2.15.270.0 · Alternative version of the Puch OEM number: 321.2.15.270.0

EUR 98.00

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