I have a Trinity 440EX. I would like to upgrade the 35.5 MM stock carb. What is the largest carb that people have used on a 440EX? I ride motocross and the dunes at times.
thanks

 

most people seem to run the 39 and 41mm fcr carbs. i have used the 39. i did like it. i know have a fcr 40mm. this 40 is a newer style is supposed to outflow the 41mm. i like it too but it is tougher to get it to mount up on a 400ex.

 

I run a 44mm lectron on my bike, I love it.

 

the only reason why i haven't tried the lectron yet is because the engine builders say they are just for mx or drag racing. otherwise you need to clean them too frequently. the engine builders said if i was to put a lectron on my 426, get the 36 or 38 at largest. larger than that would hurt performance. i have never tried it though.

 

Do the stock connections from the carb to the engine and the air box need to be changed in order to accept a 40 mm carb?
thanks

 

yes it does. the 40mm is shorter by probably close to 2 inches. so you need to make an adaptor there. also, this carb sits higher and it will rub on the gas tank.