39 Responses

  1. Markus
    Markus at |

    Very nice listings, but HEBO and Metrakit went out of businnes. Its impossible to order these parts anymore. You shoud update it. The 28mm & 30mm OKO / KOSO carbs (PWK type) you should better replace to the new generation of PWK carbs with modified bell mouth (availble from Polini, Naraku & Stage6 brands) these are working ways better.

  2. tom
    tom at |

    are you sure that for race will work fine with 4 profiles ?

  3. Tristan
    Tristan at |

    I am a little confused about the placing of the Stage 6 Racing MKII in Profile 4, mainly considering the matched exhausts. On Tuning Matters article “News: Stage6 Sport Pro MKII and Stage6 Racing MKII”
    (https://www.tuningmatters.com/2012/03/16/news-stage6-sport-pro-mkii-and-stage6-racing-mkii/) it states “In combination with an R1400 or Yasuni C21 and a 24mm+ PWK you will exceed the 18hp” neither are in the comparison chart. Some websites even compare the R1400 to the C30 power curve. I am up to purchase an exhaust for my Stage 6 Racing MKII, but have no idea. This is for a new-build spare engine for balls-to-the-wall 70cc fun!

    1. pauls6
      pauls6 at |

      What combo ended up working for you with the Stage 6 Racing MKll ? I bought it and the Polini evo 2 after running an Airsol 70cc Alum. kit for almost 3 yrs (4500 mi.) Not sure how to tell which kit it is but ordered the t-6 R piston for it. I relied on others for all my work and have since moved. I have several projects to complete. Is there a pipe that would work well on the Polini Evo 2 and the Stage 6 MKll? I have a technigas next R I ran on airsol and loved it. Bought Laser X Pro and the evo 2 was 15-20 m.p.h less with it. Bought a Yasuni off dealer in Md. who races and sold me many parts… Not sure what model or how to identify it. Also, I have a Molossi MHR Replica kit that was not enough for the Vento R4 but I now have 3 Yamaha Jog’s.. I have lots of questions..hope you and Daniel can guide me

  4. thomas
    thomas at |

    hi i have found that a pmtuning aluminium x-tech 70 cc big bore kit work incredibly well with the pmtuning x-tech 360 expansion champer pipe also know as the pm71rc pipe and a 21 dellorto carb

  5. Jakob Andersen
    Jakob Andersen at |

    I’m riding a Polini Evo 3 with a Stage6 R1400 and 28mm stage6 pwk.
    And a teamspeed 2 with a C30 and Keihin 28mm pwk both delivering more than 21hp

  6. rb
    rb at |

    i have got a aprillia sr 50 i fitted a stage 6 rep exhaust, now my bike doesnt go above 10mph what do i need to do?? do i need new rollers and air filter?? thanks

      KLOSELINE at |

      You need lighter roller most likely. Is your engine reving very high or very low?

    2. peter
      peter at |

      i would check everything ,,sounds like the exhaust has killed the engine to me ,,

  7. peter
    peter at |

    peugeot ludix ,stage 6 airsal 70cc with up jetted standard carb and motad exhaust,,loads of power ,,hard to run in under 40 mph ,,just wants to go so fast,,i would think good for 55mph cruise all day at 45mph

  8. JK
    JK at |

    What about fitting the Yasuni C16 under a 70cc Polini Corsa (Piaggio)? Atm I have a Gianelli Shot, but it just won’t work that well on that high revs as the Corsa produces, it starts to move better when the rpm’s go lower at about 60km/h. I would really like to have a slightly better acceleration than I have atm.

  9. Harley
    Harley at |

    i recently bought a 21mm tnt carb and artek reeds for my yamaha spy it has an airsal80’s kit and a technigas powerpipe with a polini air filter when i ride to the top of my rode it bogs and dies then if i keep pulling the throttle and letting it of it sometimes stays running then dies again at full throttle any clue to what it could be i have tried changing the jet (standard jet-75-80-85-95-100) and the problem is still the same?. Help would be really appriciated

  10. harley
    harley at |

    also should add of the line it wheelies and has alot of power until about 40!?

  11. Jorge Miranda
    Jorge Miranda at |

    Hi I have an airsal 70cc kit with a 21mm OKO carb… what exhaust is better for me? Yassuni R or yassuni carrera 16?

    1. Jared K
      Jared K at |
    2. Jared K
      Jared K at |


      70cc exhaust shootout with the ones you’re looking at.

    3. Jared K
      Jared K at |

      Also what rpms are you running up into? The stage 6 pro or pro replica i forgot which one is the one that has one of the highest hp but if you are really revving your engine out the it is the clear winner because it keeps on making power while many others fall off hard.

    4. Jared K
      Jared K at |


      Here is a very good write up on testing many pipes and cylinders.

  12. Jorge Miranda
    Jorge Miranda at |


  13. Jared K
    Jared K at |

    Where would a Arrow Extreme exhaust fall into these categories?

  14. j.larsen
    j.larsen at |

    hope you can help me
    i have a piaggio zip 50 t2 2013 model
    it have 2300 km on the clock
    i fitted a arrow exhaust to it now it go 80 kph for 1 km then slow down to 45 kph i shout of for a few minutes and go again 80 kph and start all over
    this is the only modification i have don

  15. pauls6
    pauls6 at |

    Will the C-21 work for the Stage 6 MKll Racing and Polini Evo 2 ?What type of Fuel will I need to run with these kits? 93 octane unleaded is top around here but VP race fuel and general aviation gas is available.. Use? Precautions ? How do I hide all the wires when Changing handlebars and controls. Better brakes and suspension for the Jog (’00). I have the 24mmPWK by S-6R, 21mm Del black edit. and 19mm Arrechi. Get back with me and I will get my stuff sorted and hopefully you can guide me.

  16. Dieter
    Dieter at |

    Hi Daniel,
    Great site mate!
    Good information with a good range of data backing the claims too.
    I notice the Technigas Triops doesn’t feature in the above list?
    I’ve just paired an Alloy Malossi MHR replica 70cc with it (it was previously running with my stock 50cc setup) and was wondering which Carb. I notice the 17.5mm delorto with the polini / mhr combo. Could I expect similar compatibility with the Triops?

    Cheers Mate.

  17. Daniel
    Daniel at |


    I have a quick question. I am thinking to upgrade my Peugeot Speedfight LC. I have only the Polini 70cc kit. I need all material, from exhaust to carburator. Could you help me?

    I am thinking for the exhaust the Hebo, because I saw all exhaust test here in the forum. What you think?

    And the carburator? 19, 21 or 24?

    Thanks so much for all help.

  18. Erin
    Erin at |

    Thanks for all the information I am new to all of this and that was a lot of good stuff thanks

  19. Julian
    Julian at |

    I’m riding a polini evolution 50 lc on my honda px-r.
    Which dpr 50 exactly do you mean?
    Are any other exhausts that work good on this cylinder?
    At the moment i got a bidalot c20 and a polini cp 19 mounted.
    Works pretty well but i need more power for riding in the dirt.

    Greet’s from germany

  20. Furman Eddings
    Furman Eddings at |

    Hey I just got a genuine roughhouse sport with 12 inch wheels. ordereda MHR exhaust) molassi )19 carb n 70 cast Q:can I run the exhaust without putting the new carb and piston on and add 10 to the jet? Top speed is great just need a little more take off. Thank you this is the only place I’ve found anything useful on the subject.

  21. Luke
    Luke at |

    Hi Daniel……I bought a st6 streetrace kit with 21mm delorto carb, st6 variator kit, st6street exhaust, clutch springs for my 06 bws. I’m a daily driver jus looking for a lil extra speed(nothing crazy). Wondering if I need to install the carb or will the stock carb be suitable? I’d also like to use the stock airbox! I’d like to acheive a top speed of at least 80-85 Kph. I understand I could acheive more but I want reliability over peak performance and would like to avoid upgrading my crankshaft. Please advise:)


Leave a Reply