Vypínání motoru, špatné startování, nedostatečný přívod paliva a další problémy s palivem často způsobuje poškozený ventil paliva.
| ATU-Race GT50 | | | |
| ATU-Spin 50 GE | | | |
| Adly (Her Chee)-Air Tec 50 | | |
| Adly (Her Chee)-Noble 50 | | |
| Adly (Her Chee)-Panther 50 | | |
| Baotian-BT49QT-18C1 B010 (1E40QMA) | |
| | | | | |
| Baotian-BT49QT-18E1 Rocky (1E40QMA) | |
| Baotian-BT49QT-18F1 Tanco (1E40QMA) | |
| Baotian-BT49QT-20C (1E40QMA) | |
| Baotian-BT49QT-28A (1E40QMA) | |
| Benelli-49X QuattronoveX 50 | | |
| Benzhou-YY50QT-27 | | | |
| CPI-ARAGON | | | |
| CPI-ARAGON GP | | | |
| CPI-BINGO / TENNESSE do 2003 | |
| | | | | |
| CPI-FORMULA R od 2008 | | |
| CPI-FREAKY | | | |
| CPI-HUSSAR (E1) do 2003 | | |
| CPI-HUSSAR (E2) od 2003 | | |
| CPI-MARS/POPCORN (E2) od 2003 | |
| CPI-MARS/POPCORN (E1) do 2003 | |
| CPI-OLIVER (E1) do 2003 | | |
| CPI-OLIVER (E2) od 2003 | | |
| CPI-OLIVER City 50 od 2005 | | |
| | | | | |
| CPI-OLIVER Sport 50 ab 2005 | | |
| Generic-Ideo 50 | | | |
| Generic-Spin 50 GE | | | |
| Generic-XOR 50 | | | |
| Honda-Vision 50 SA50 AF29 | | |
| Keeway-ARN 50 2009-> | | |
| Keeway-EASY 50 2009- | | |
| Keeway-F-ACT 50 2009- | | |
| Keeway-F-ACT 50 NKD Naked | | |
| | | | | |
| Keeway-F-ACT 50 Racing SP 2009- | |
| Keeway-FLASH 50 | | | |
| Keeway-FOCUS 50 | | | |
| Keeway-GOCCIA 50 | | | |
| Keeway-HACKER 50 2009- | | |
| Keeway-HURRICANE 50 | | |
| Keeway-MATRIX 50 -2008 (V1, V2) | |
| Keeway-MATRIX 50 SP 07-08 (V3) | |
| Keeway-MATRIX 50 SP 2009- (V4) | |
| | | | | |
| Keeway-PIXEL 50 2009- | | |
| Keeway-RY6 50 -2008 | | |
| Keeway-RY6 50 -2008 | | |
| Keeway-RY8 50 -2008 | | |
| Keeway-RY8 50 EVO | | |
| Keeway-RY8 50 Racing | | |
| Keeway-RY8 50 SP | | | |
| Keeway-SWAN 50 2009- | | |
| Keeway-Venus 50 2T | | |
| | | | | |
| Longjia-LJ50QT-F | | | |
| Longjia-LJ50QT-F-01 | | | |
| Longjia-LJ50QT-K | | | |
| Malaguti-F12 Phantom 50 AC (od 2007-) motor CPI |
| Mawi-Desire Race 50 2T | | |
| Mawi-Power Star 50 2T | | |
| Mawi-Racing Power 50 2T | | |
| Motofino-MF50QT-2 50 2T | | |
| Motomojo-Roadster 50 2T | | |
| | | | | |
| Motomojo-Uptown 50 2T | | |
| Motorro-City Hooper 50 | | |
| Motorro-Polly 50 | | | |
| Motorro-Sprint 50 | | | |
| Motorro-Tria 50 | | | |
| MuZ / MZ-Moskito Classico 50 2T | |
| MuZ / MZ-Moskito FB50 Base 2T -2002 | |
| MuZ / MZ-Moskito FB50 Base 2T 2003- | |
| MuZ / MZ-Moskito RX 50 2T -2002 | |
| | | | | |
| MuZ / MZ-Moskito RX 50 2T 2003- | |
| MuZ / MZ-Moskito SX 50 2T -2002 | |
| MuZ / MZ-Moskito SX 50 2T 2003- | |
| Powersports Factory-Viaggio RX8 50 2T | |
| Qianjiang-B-05 50 2T | | | |
| Qianjiang-B-08 50 2T | | | |
| Sachs-Eagle 50 | | | |
| Sachs-SX1 | | | |
| Sachs-Speedforce R | | | |
| | | | | |
| Sachs-Speedjet 50 | | | |
| TNG-LS49 50 2T | | | |
| TNG-SS49 50 2T | | | |
| TNG-Venice 49 50 2T | | |
| Tank-Classic 50 2T | | | |
| Tauris-MAMBO 50 | | | |
| Tauris-SAMBA 50 | | | |
| Vento-Triton 50 2T | | | |
| Vento-ZIP 50 2T | | | |
| | | | | |
| Yamati-RX8 50 2T | | | |
