Problem with MHR team 80

[jordan17]

Hello guys i am realy sorry for writing in english but couldnt find a forum in english!
So i just got an MHR team 77cc 50mm bore cylinder on my derbi senda drd 2003 sm and I am trying to run a dellorto 21mm carb and a jasil crank and a i think its the metra kit pro exhaust (its not the one that goes under the bike).
My problem is that i cannot open full throttel without the bike just bugging and starting to die (turn off), so what happens when i open full throttle, well nothing happens!!
Is the carb too small do I need a 26mm? Is it the exhaust because i've seen guy a guy run it with the same exhaust (i think)?
Thanks a lot!!!!
P.s could you please try and answer in english.

[MiKeY]

Have you re-adjusted the carb?
I mean, did try putting a bigger jet in it?
Maybe there's just some dirt in the carb or one of the jets...?

[jordan17]

I have jetted the carb a bunch from 88 to 124 fiddled with the screws and the needle!!
But the funny thing is i can run the bike on 1/4 throttle but when i open it more it starts to like lag cough or whatever, and if i go full throttle it just starts to turn off!
I am scared that the exhaust is too weak but i also think i should get a 26 mm carb!!

[rené]

you first have to get a bigger carburettor, I should put jet 130 in a 26mm carbu.

[basserd]

No bigger is not neccery.
Ik think you need a bigger jet
Or the inlet is not air tite

Sorry voor me goede Engels XD

[rené]

No bigger is not neccery.
Ik think you need a bigger jet
Or the inlet is not air tite

Sorry voor me goede Engels XD

well let's say a bigger carburettor is smarter.