INTAKE MANIFOLDS
Intake manifold conveys the air-fuel mixture to the engine by means of reed valve.
The total efficiency of an engine is calculated as the product of various partial efficiencies, such as:
- volumetric efficiency
- thermodynamic efficiency
- mechanical efficiency
Volumetric efficiency is the ratio between the quantity of fuel that can enter the combustion chamber and the displacement of the engine.
One of the main factors affecting volumetric efficiency is loss due to friction that the fluid encounters (air-fuel mix) when feeding from the air filter to the combustion chamber. Therefore, one of the components that greatly influences this loss is the intake manifold, since all of the mix has to travel through it with the minimum possible loss. For this reason, sudden increases in section and corners along the mix path must absolutely be avoided.
The intake manifold also acts as an accumulation tank for the fresh load, since the mix, travelling at a certain speed, requires time to stop when the reed valve closes. Therefore, mix collects in the manifold and exerts pressure against the reeds. For this reason, each manifold has a well-defined range of revolutions within which it provided maximum efficiency (tuned manifold).
In addition, the manifold supports the carburettor by connecting it to the engine casing or to the cylinder, damping vibrations between casing and carburettor and preventing emulsion of gas and air in the carburettor tank.
This apparently simple component therefore requires a great deal of study in order to take full advantage of all of its qualities.
Malossi engineers have achieved this to perfection. Malossi, with decades of experience in engine fuelling systems, has created a new line of manifolds in rubber and aluminium alloy for the new generation of scooters, and has tested and developed the line on roads and race tracks.
Malossi rubber manifolds feature a composite structure. Their construction begins with an aluminium insert that is encased in a special plastic material that is impervious to oils and fuels, guaranteeing increased rigidity at the point of attachment to the casing and greater flexibility of the manifold body.
Derbi - Minarelli engines : APRILIA - HONDA - PIAGGIO
| Code | Material | INTER-AXIS mm | Ø hole | Ø manifolds | Ø inlet | total lenght | carburettor applications | Note |
| 02 6639B | NBR | 61x40 | 6,5 | 30 | 35 | 27 | PHBH 26-30 VHST 26-30 | Not suitable for original air box filter |
Piaggio - Gilera 2T 50 engines : APRILIA - DERBI - GILERA - ITALJET - PIAGGIO
| Code | Material | INTER-AXIS mm | Ø hole | Ø manifolds | Ø inlet | total lenght | carburettor applications | Note |
| 02 7528B | NBR | 52 | 6,5 | 26 | 30 | 31,5 | PHBL | Not suitable for original air box filter |
| 02 8480B | NBR | 52 | 6,5 | 22 | 28 | 26 | PHVB 22 | For original air box filter |
| 02 5733B | NBR | 52 | 6,5 | 20,5 | 23 | 26 | ORIGINALS PHVA 12-17,5 PHBG 15-21 | Original spare Ø 20: for original air box filter |
Yamaha - MBK - Minarelli horizontal 2T 100 engines : APRILIA - BENELLI - ITALJET - MBK - YAMAHA
| Code | Material | Ø hole | Ø manifolds | Ø inlet | total lenght | carburettor applications | Note |
| 02 8399B | NBR | 6,7 | 22 | 28 | 24,5 | PHVB 22 | For original air box filter |
| 02 8481B | NBR | 6,7 | 21 | 23 | 24 | ORIGINALS PHVA 12-17,5 PHBG 15-21 | Original spare Ø 20: for original air box filter |
Yamaha - MBK - Minarelli vertical 2T 50 engines : APRILIA - ITALJET - MBK - YAMAHA
| Code | Material | INTER-AXIS mm | Ø hole | Ø manifolds | Ø inlet | total lenght | carburettor applications | Note |
| 02 8400B | NBR | 58x35 | 6,5 | 20,5 | 23 | 19 | ORIGINALS PHVA 12-17,5 PHBG 15-21 | Original spare Ø 20: for original air box filter |
| 02 8479B | NBR | 58x35 | 6,5 | 21 | 27 | 19 | PHVB 22 | Not suitable for original air box filter |
Products reserved exclusively for racing in specifically designed locations according to the provisions of the competent sporting authorities. We disclaim all liability for improper use
Vehicle compatibility (56 vehicles)
Aprilia(7)
- MOJITO CUSTOM 50 2T
- SPORTCITY ONE STREET 50 2T euro 2
- SR (carb.) 50 2T LC 2004→ (PIAGGIO)
- SR MOTARD 50 2T euro 2
- SR R (carb.) 50 2T LC (PIAGGIO)
- SR R 50 2T LC euro 4 2018→ (PIAGGIO CA81M)
- SR Street 50 2T LC euro 2
Derbi(5)
- ATLANTIS - BULLET 50 2T 2003→
- GP1 50 2T LC
- GP1 OPEN 50 2T LC
- GP1 REVOLUTION 50 2T LC
- VARIANT Sport 50 2T
Gilera(10)
- DNA 50 2T LC
- EASY MOVING 50 2T
- ICE 50 2T
- RUNNER 50 2T LC
- RUNNER SP 50 2T LC 2006→ (C451M)
- RUNNER SP 50 2T LC ←2005
- STALKER 50 2T
- STORM 50 2T
- TYPHOON 50 2T
- TYPHOON X 50 2T
Italjet(2)
- JET SET 50 2T
- TORPEDO 50 2T
Piaggio(26)
- DIESIS 50 2T
- FLY 50 2T
- FREE 50 2T
- LIBERTY 50 2T
- NRG 50 2T LC
- NRG EXTREME 50 2T
- NRG EXTREME 50 2T LC
- NRG MC2 50 2T LC 1998→
- NRG MC2 50 2T LC ←1997
- NRG MC3 DD 50 2T LC
- NRG MC3 DT 50 2T
- NRG Power 50 2T LC euro 4 2018→2020 (CA71M)
- NRG Power DD 50 2T LC
- NRG Power DT 50 2T (C453M)
- NTT 50 2T LC
- QUARTZ 50 2T LC
- SFERA 50 2T
- SFERA 75 2T
- SFERA RESTYLING 50 2T
- TYPHOON 50 2T 2007→2010
- TYPHOON 50 2T euro 2 2011→2017 (C421M)
- ZIP 50 2T 2000→ (C25EM)
- ZIP 50 2T ←1999
- ZIP Fast Rider 50 2T
- ZIP SP 50 2T LC 2001→
- ZIP SP 50 2T LC ←2000
Vespa(6)
- ET2 50 2T 2000→
- ET2 50 2T ←1999
- LX 50 2T
- Primavera 50 2T euro 2 (C533M)
- S 50 2T euro 2 (C381M)
- Sprint 50 2T euro 2
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