440ex?

[cameront400]

i have a 400ex and im wanting to put a 440 big bore kit in it..... and i was wondering how reliable they are and wat stuff i would have to get to make it reliable.... i have kibblewhite black diamond valves and i think i have heavy duty head studs.....and how hard are they to put in? thanks....

[XXXRACER165]

What 440 kit is it? I have a IMS kit in mine and have been running it 3 full seasons. NOT a lick of problems. The valves and studs are a great thing to have not hard to install and hold up great. I think your on the right track budd:) :macho

[Big - D Racing]

440's are very reliable, well let me rephrase that they are as reliable as the builder who built it. If they are built correctly they will run forever just like the stock motor. Make sure you build the rest of the bike to match the motor meaning better exhaust, better carb, etc. Make everything match. If you put in a big 440 and then you have all stock components around it it will basically sufficate it, cause heating problems, etc. Build it right and it will last forever. I'll put mine against any 450 and any other built 400ex. Only thing I lose to are built 450's and the big stroker 400ex's.