
The legend is back—and bigger than ever! The legendary Metrakit racing cylinder from days gone by has risen like a phoenix from the ashes in its 45 mm version, reigniting the passion in your Puch Maxi S, N, X30 Sport NS, NL, and Supermaxi LG1 and LG2 mopeds.
The aluminum cylinder with a gray cast iron liner is an optimized replica of the original Metrakit racing cylinder. The valve timing has been revised compared to the original and features more exhaust advance, making the well-known piston seizure problem caused by high heat generation a thing of the past. In addition, the cylinder height has been precisely adjusted, so that the extra-thick base gasket previously required is now unnecessary.
This GPO racing cylinder is among the strongest and most powerful in its class and has been extensively tested. It delivers robust torque across the entire power band and offers impressively powerful performance. Thanks to the optimizations compared to the original, the cylinder also achieves a noticeably higher RPM, which provides even more power and riding enjoyment.
To get the most out of this tuned cylinder, we recommend using at least a 15-mm carburetor. However, you’ll achieve noticeably more power with a 17-mm carburetor. Thanks to the generous 19-mm intake, you’ll have plenty of headroom for optimal power delivery.
Note: The cylinder is shipped loose and without a piston, gasket set, studs, or other mounting parts.
A high-quality, affordable standard replacement part. GPO – GOOD PARTS ONLY.
| Nominal diameter | 45 mm |
| Manufacturer | GPO |
| Camouflaged | No |
| Material | Aluminum, Gray cast iron |
| Surface | varnished |
| Displacement | 70 ccm |
| Crankshaft stroke | 43 mm |
| Area of application | Tuning, Racing |
| Ø cylinder neck | 47.8 mm |
| Hole spacing inlet | 38 mm |
| Hole spacing for cylinder mounting | 44 mm |
| Outlet type | straight |
| Hole spacing outlet | 42 mm |
| Cooling type | Airstream cooling |
| Number of fixing points | 4 pcs |
| Puch | E50 ZA50 (air-cooled) Z50 (X30 Sport) |
Accessories & related products
swiing® revival Stud Bolt, Inlet/Outlet M6x30 (Grade 10.9)
Manufacturer: swiing® revival parts · Material: Steel · Surface: galvanized (blue) · Thread type: M6x1 (standard thread) · Diameter: 5.95 mm · Nominal diameter (thread): 6 mm · Total length: 30 mm · Thread length: 12 mm · Strength class: 10.9
2,10 EUR
swiing® ingenious 15 mm carburetor set camouflaged | Puch E50
Nominal diameter: 15 mm · Manufacturer: swiing® ingenious parts · Camouflaged: Yes · Component group Carburetor: Carburetor complete · Area of application: Tuning · Carburetor type: SRE · Choke control: Hand choke · Nozzle thread: M3.5x0.6 (standard thread) · Mounting type: Plug connection clamped · Mounting type: Stud bolts & nuts · Nozzle size: 62 · Ø Inside entrance: 15 mm · Ø Output inside: 15 mm · Ø Air filter connection: 20 mm · Hole spacing inlet: 38 mm · Ø Internal connection: 20 mm · Ø fuel hose connection: 5 mm · Ø fuel hose connection: 6 mm · Clamping screw torque (max.): 4 N/m
122,40 EUR
swiing® ingenious resonance exhaust set Ø 28 / 70 mm | Puch Maxi, X30 Sport
Manufacturer: swiing® ingenious parts · Material: Steel · Surface: chrome-plated · Ø outside: 70 mm · Total length: 730 mm · Color: Chrome · Ø Internal connection: 28 mm · Exhaust type: Cigar · Mounting type: Screwed clamp · Flame tube attachment: Flange
139,90 EUR
Not in stock
GPO 45 mm piston (Metrakit replica) | Puch
Nominal diameter: 45 mm · Manufacturer: GPO · Material: Aluminum · Ø outside piston (A): 44.93 mm · Compression height (C): 23.25 mm · Curvature (D): 2.85 mm · Total piston height (E): 49.6 mm · Number of piston rings (F): 2 pcs · Piston ring mold: L-ring · Piston ring mold: Rectangular ring · Piston ring impact: Internal fuse (IS) · Ø piston pin (B): 12 mm · Piston ring height: 1.55 mm · Piston ring height: 2 mm · Thick piston ring: 1.8 mm · Thick piston ring: 1.9 mm · Weight piston kit: 98 g
58,20 EUR
GPO gasket set 43.5 & 45 mm (Metrakit replica) | Puch
Manufacturer: GPO · Material: Aluminum · Material: Graphite / Graphite · Material: Sealing carton · Ø cylinder: 43.5 mm · Ø cylinder: 45 mm · Number of components: 4 pcs · Thickness: 0.4 mm · Thickness: 0.5 mm · Thickness: 2.6 mm · Ø outlet inside: 26.5 mm · Hole spacing inlet: 38 mm · Hole spacing outlet: 42 mm · Hole pattern [mm]: 44 X 44
17,40 EUR
GPO 43.5 mm cylinder kit (Metrakit replica) | Puch
Nominal diameter: 43.5 mm · Manufacturer: GPO · Material: Aluminum · Material: Gray cast iron · Surface: varnished · Displacement: 64 ccm · Crankshaft stroke: 43 mm · Ø cylinder neck: 47.8 mm · Ø outlet inside: 26 mm · Ø Inlet inside: 19 mm · Thread inlet: M6x1 (standard thread) · Hole spacing inlet: 38 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 · Area of application: Racing · Area of application: Tuning
169,10 EUR
GPO 45 mm cylinder kit (Metrakit replica) | Puch
Nominal diameter: 45 mm · Manufacturer: GPO · Material: Aluminum · Material: Gray cast iron · Camouflaged: No · Surface: varnished · Area of application: Racing · Area of application: Tuning · Crankshaft stroke: 43 mm · Displacement: 70 ccm · Ø cylinder neck: 47.8 mm · Ø outlet inside: 26 mm · Ø Inlet inside: 19 mm · Ø piston pin (B): 12 mm · Thread inlet: M6x1 (standard thread) · Hole spacing inlet: 38 mm · Outlet type: straight · Number of fixing points: 4 pcs · Hole spacing outlet: 42 mm · Thread outlet: M6x1 (standard thread) · Hole pattern [mm]: 44 x 44
186,60 EUR
GPO 21 mm intake manifold Dell'Orto PHBG | Puch E50 / Z50 / ZA50 (wind cooled) / ZA50 (Cat.)
Manufacturer: GPO · Material: Aluminum · Ø inside: 21 mm · Ø External connection: 26 mm · Hole spacing inlet: 38 mm · Total height: 68.6 mm · Mounting type: Stud bolts & nuts · Area of application: Racing · Area of application: Tuning · Number of fixing points: 2 pcs · Total length: 85.5 mm
40,30 EUR
Metrakit Air Filter, 37/32 mm, Straight, for Dell'Orto PHBG Carburetor
Manufacturer: Metracite · Material: Aluminum · Camouflaged: No · Material: Rubber · Area of application: Racing · Color: black · Color: red · Filter type: Foam · Total length: 55 mm · Length rubber part: 15 mm · Mounting type: Bride · Length of filter section: 22 mm · Ø outside: 81 mm · Ø Internal connection: 32 mm · Ø Internal connection: 37 mm
43,80 EUR
Explore categories from Cylinder
Moped fans also bought
swiing® revival Stud Bolt, Inlet/Outlet M6x30 (Grade 10.9)
Manufacturer: swiing® revival parts · Material: Steel · Surface: galvanized (blue) · Thread type: M6x1 (standard thread) · Diameter: 5.95 mm · Nominal diameter (thread): 6 mm · Total length: 30 mm · Thread length: 12 mm · Strength class: 10.9
2,10 EUR
GPO 45 mm cylinder head tuning black | Puch Maxi S, N, X30 NS, NL, N-2AH
Manufacturer: GPO · Material: Aluminum · Camouflaged: Yes · Surface: varnished · Width: 125 mm · Height: 55 mm · Total length: 135 mm · Ø cylinder: 45 mm · Area of application: Tuning · Number of fixing points: 4 pcs · Decompressor: No
50,10 EUR
swiing® ingenious 17 mm SRF carburetor camouflaged | Puch Maxi, Supermaxi, X30 NS / NL
Nominal diameter: 17 mm · Manufacturer: swiing® ingenious parts · Material: Aluminum · Camouflaged: Yes · Component group Carburetor: Carburetor complete · Area of application: Tuning · Carburetor type: SRE · Width: 47 mm · Choke control: Hand choke · Nozzle thread: M3.5x0.6 (standard thread) · Mounting type: Plug connection clamped · Nozzle size: 74 · Ø Inside entrance: 17 mm · Total length: 65 mm · Ø Output inside: 17.1 mm · Ø Air filter connection: 27.5 mm · Height: 89 mm · Height: 109 mm · Ø Internal connection: 23 mm · Ø fuel hose connection: 5 mm · Mixed oil connection: No · Vacuum connection: No · Nozzle block: 2.2 · Clamping screw torque (max.): 3 N/m · Clamping screw torque (max.): 4 N/m
139,90 EUR
swiing® ingenious intake manifold 17 mm SRF camouflaged | Puch E50
Manufacturer: swiing® ingenious parts · Material: Aluminum · Camouflaged: Yes · Ø inside: 17 mm · Number of fixing points: 2 pcs · Ø External connection: 23 mm · Total length: 38 mm · Hole spacing inlet: 38 mm · Area of application: Performance · Area of application: Racing · Area of application: Tuning · Height flange center hole: 42 mm · Total height: 53.5 mm · Mounting type: Stud bolts & nuts
52,40 EUR
GPO 45 mm piston (Metrakit replica) | Puch
Nominal diameter: 45 mm · Manufacturer: GPO · Material: Aluminum · Ø outside piston (A): 44.93 mm · Compression height (C): 23.25 mm · Curvature (D): 2.85 mm · Total piston height (E): 49.6 mm · Number of piston rings (F): 2 pcs · Piston ring mold: L-ring · Piston ring mold: Rectangular ring · Piston ring impact: Internal fuse (IS) · Ø piston pin (B): 12 mm · Piston ring height: 1.55 mm · Piston ring height: 2 mm · Thick piston ring: 1.8 mm · Thick piston ring: 1.9 mm · Weight piston kit: 98 g
58,20 EUR
GPO gasket set 43.5 & 45 mm (Metrakit replica) | Puch
Manufacturer: GPO · Material: Aluminum · Material: Graphite / Graphite · Material: Sealing carton · Ø cylinder: 43.5 mm · Ø cylinder: 45 mm · Number of components: 4 pcs · Thickness: 0.4 mm · Thickness: 0.5 mm · Thickness: 2.6 mm · Ø outlet inside: 26.5 mm · Hole spacing inlet: 38 mm · Hole spacing outlet: 42 mm · Hole pattern [mm]: 44 X 44
17,40 EUR
GPO 45 mm cylinder kit (Metrakit replica) | Puch
Nominal diameter: 45 mm · Manufacturer: GPO · Material: Aluminum · Material: Gray cast iron · Camouflaged: No · Surface: varnished · Area of application: Racing · Area of application: Tuning · Crankshaft stroke: 43 mm · Displacement: 70 ccm · Ø cylinder neck: 47.8 mm · Ø outlet inside: 26 mm · Ø Inlet inside: 19 mm · Ø piston pin (B): 12 mm · Thread inlet: M6x1 (standard thread) · Hole spacing inlet: 38 mm · Outlet type: straight · Number of fixing points: 4 pcs · Hole spacing outlet: 42 mm · Thread outlet: M6x1 (standard thread) · Hole pattern [mm]: 44 x 44
186,60 EUR
AKOA 45 mm Cylinder Head, Black | Puch E50 / Z50 / ZA50 (Air-Cooled) / ZA50 (Cat.)
Manufacturer: AKOA · Camouflaged: No · Area of application: Tuning · Material: Aluminum · Surface: varnished · Total length: 132.2 mm · Ø cylinder: 45 mm · Width: 123.2 mm · Height: 54.5 mm · Number of fixing points: 4 pcs · Hole pattern [mm]: 44 x 44 · Decompressor: No
52,40 EUR












