I am trying to decide on putting a big bore kit on my ex or saving up a while and getting a LT250R. I used to have a quadracer so i know what im getting myself into. I just was wondering how much power a 416 kit added. Hows the hp numbers? Thanks.

If you are going to fully build a 416 you will keep up with a slitly moded lt250. I have raced a few and it all depends on the mods and the rider. I can beat cheaply built 440s. If i were you i would completely build a 440 with 13:1 compression if this is in your budget. I did a 416 because it is all i could afford. Now i am saving to change my rod out to up my compression and do a 440 or a 460 stroker. Not sure yet. My mods are listed below. A 416 alone will make a dif but not much. You need to do it all to get the power. I have about 3k into my motor exhaust, carb and any labor i didnt want to do ym self. Not cheap. If you want to do all out drag do the LT250 and put 2k into that. What eva.. good luck

Its not really that i cant afford it, i just want my machine to be nearly as reliable as stock and not to run very hot.

Yes heat is an issue. My bike is jetted a little on the lean side so it runs hotter. It gets hot. It depends i guess. Heat will increase but so will power. It is a trade of with these 4 strokes. Call around. Give LRD, Sparks, Powroll and CT racing and see what they can tell you. Allt these companys are great and should bea ble to fill you in or give you an idea of what to do. As far as reliability goes my 416 is basically moded as far as i can go without bigger valves and i have never had a problem. Only human inflicted errors. Stupid me..

Good luck

You might want to check out the factory parts you will need for the LT250. If I'm right they are mostly discontinued. I know the whole transmission and kick starter gears for some years are gone now.