just picked one up today and the other post say to run a 180-200 main but do you use the needle jet in the 34 or the 30 or are they the same i have'nt took it apart yet to see but thinking there different size and also what about the pilot jet leave the 34 in or take out and put in the one from the 30 thanks

 

You can keep everything the same except the main jet. When I first did this a year ago someone told me to interchange some parts from the 30mm to the 34mm carb but it never ran right so I put all the origional parts back into the 34mm carb and just went with a smaller main jet and it has ran great ever since. The only thing that you need to make sure you have is the brass choke fitting that came with the 34mm carb because the fitting from the 30mm will not fit. This is a must to make it work or it will not run. Do you have any other mods done because if you do or dont this will change the main jet size. If you have a pipe and running a bolt on filter then a 180-185 would be good but if you are stock a 160-165 would be good. I have all the different sizes that you can use for different mods. It will make a big difference once tuned right.

 

2-many yes it's piped milled head and ported and yes i have the brass fitting say has anyone tried the ufo plugs/discs that fit in the bottom of the slide i got some from a buddy going to try them out unless they don't work? thanks

 

With the mods that you have then 180-185 will be perfect. The ufo you need to change the pilot jet. Im not to familliar with the ufo setup but Modquad is. Try it without the ufo first and see how you like it. Doing the ufo will change the airflow and I dont think anyone has the correct jetting when using the 34mm carb with the ufo installed on a 250. This might be dangerouse for you. This is an area that you CANT guess at. If im not mistaken I am one of the first people on this sight to install a 34mm on the trailblazer and no one could tell me the correct jetting. I did alot of research and found out what works and what dont. This is a new thing that many people have been trying and asking me about what I did to install the 34mm carb. I can tell you that it was worth the patience and the headache.

 

yeh i have the ufo. was already on the carb. running a 185 jet. they say you need to run a #15 piolet jet. i need to ask modquad wfats in there. i like the ufo. does not have the hesitation when giving it the throttle. modquad and 2manytoys helped me out alot. cant think them enuff. ive learned alot about carbs on atvs from doing this. cant spell lol

 

Curb,

I think modquad said he had a 30 or 35 pilot jet in that carb. Not sure though. How do you like the carb?

 

hey guys what are some good compression #s on pump gas before you have to run race fuel and will this 34mm make a noticeable difference

 

A 14:1 race head is needed before you really need to run racing gas. I am running a 12.5:1 head on mine and I use a mixture of gas, but I really don't have to. The carb should make a pretty good difference.

 

how about lbs the cylinder will pump mine is 128 lbs the other post said 115 min whats stock if anyone knows need to know how many lbs thanks

 

yo 2manymany like the carb really woke it up. thought the stage 1 kit woke it up. adding the bigger carb was perfect for it....