Carb size

[Andreb84]

I built a 421 with cpi inframes vforce 4s cylinders are dune ported. i have two sets of carbs...a pair of 39mm pjs and a pair of 28mm pwks

 

Im doing mostly trail riding which set should i use??

[sheerider11]

Who ported/assembled the motor. They would be the person to ask. Not randos on the interwebz. Cause its not my bike and I could have no clues.

So with that being said. Stock carbs will be fine.

[Andreb84]

Yeah i was leaning towards the 28's nobody wants pjs for whatever reason

[trickedcarbine]

Stock cyl or cub? What type of riding, tight idiot holes in the north west or wide open dunes? The 28's will be pretty responsive and only be a few horses less on the top end. If it's not just wide open areas and drag racing the 28's would be the way to go if you don't wanna get a set of 35's

[trickedcarbine]

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Edited March 9, 2016 by trickedcarbine

[fastrthnu]

Id go with the 28s as well. 

[Andreb84]

Sleeved stock cylinder...you pretty much answered my question though i was wondering what i would lose on my top end going with small carbs...but then going with big carbs i dont wanna lose all my bottom end either...best solution is to get 33s or 35s but as long as the 28s feed the motor decent i"ll work with those

[87sheerips]

28's will work awesome. Bumping to 35's you will lose a little snappiness but gain up top... At least that's what I experience being a shitty tuner