I,m building up my son Trx 90 The engine mods as follows Ported head TBQ Race cam from Beatrice cycle and a 114cc cylinder kit With Flat top piston, stepped header pipe to stock muffler. Heres the Question The carb do I run the stock carb and jet it up I think its 19mm bore or run a Honda trx125 carb which is 22mm bore larger size and go fron their??

 

Ask The Editors: Do I need a Bigger Carb For My Big-Bore? | ATVConnection.com

 

Ask at atvriders.com in the mini forum.
They can tell you what works.
Neither carb is big enough.