Which Mainjet should I use? Question to everyone who has a Mikuni TM24 Carburateur

[Sprengmeister]

Hello,

I have a querstion referring to my scoot.

I have a SR50 LC Minarelli, which is a sprint scoot.
My setup:
MHR Speed cilinder stage 5 FKT
MHR crankshaft
Stage 3 FKT Motorblock
MHR Overrange Kit with 3,6 g - 4,7g rolls, I test these days
MHR Delta Clutch with the black springs
MHR Wingbell
MHR red big spring between delta clutch and overrange
Yasuni C20 exhaust
Mikuni TM 24 carburateur with 220er Mainjet
Tommaselli gas grap
and some stuff which everybody has in a high end scoot

So, I don´t know anyone who has a Kit like these on Minarelli, only a lot of people have a Kit like this on Piaggio with a Mikuni TM24 Flatside carburateur.
On Minarelli some people like Cozmo have a Keihin PWK 28, but this has no use for me.

So, can someone tell me what a Mainjet should I use?
I have 1:40 in my tank.
I come from Germany and can´t speak Dutch, so please forgive me
Please answer in English

Thanks a lot, many greetZ to Netherland and hope to see you on Scooter-Attack Weekend 20+21. September on Nürburgring

Ciao Carsten

 

[Menno]

Whats the problem with the 220 mainjet..too poor, too rich?

 

[Chiel]

Depends on what kind of air filter you are using. Normaly the main jet is between 180 and 230, so just look at your spark plug and adjust if nessesary.

 

[RobvdZande]

I had @ Pia with Evo70 an 190 mainjet...

 

[Sprengmeister]

I have a MHR Air Filter like a lot of people in NL.
I think the Mainjet is too big, have tested everyone between 190-230 and now I have also everyone from 150-185 so I will look again.
At the spark plug is a little bit oil and its a little bit black, so not really brown.

http://sprengmeister.sangel.de/neu3.JPG
http://sprengmeister.sangel.de/neu6.JPG
http://sprengmeister.sangel.de/neu2.JPG

here are some pics of my scoot. I don´t know really what the problem is...I´m have tuned many scoots before and now with 19 years and so on, but I don´t know what to do now really...

thanx for all replies...

Ciao and merci Carsten

 

[tiba_karotsu]

i used to have Mikuni TM24 carb and it ran fine with 165 main jet (stock was 170). get jets with 165 & 160 size i presume you premix oil in your gasoline, how much oil per liter then? this also affects jetting too.

now i sold the mikuni carb & got a Dell'Orto 28 PHBH and it's been running great ever since.

 

[bruteorage]

I have got a hebo manston 2 with a 24mm mik fs with a 250 (homemade) mainjet and its running great

 

[Aerox-Evo70]

a friend of me has almost the same setup.. evo70 FKT, c20, mikuni 24 etc, and he has a mainjet 220 (without filter)

 

[Velo]

I Drill my jets my self.

Something in the near of 1.00 mm - 1.15 mm Is what I can advise.
I am using a K&N cone filter.

Fuel is 98% 95 oct. Un. lead and 2% Motul 800.

 

[Armon]

I've got almost the same setup as you, and i drive with a 210 mainjet with a Hebo filter. The only difference between your setup and mine is that your speed cilinder is tuned and mine untuned.

Fuel that i use is super 98oct in combination with castrol 747 1:35

 

[nrg69]

hi!I have zip sp mhr team with 24mik and polini evo filter.I use a 190 mainjet