hey, we have already tried it. a bike with a cam, higher compression piston, and jetting will be quicker than the same bike with a full pipe and jetting. we did it on a 400ex. yes, a pipe will open it up much more with these mods, but when comparing the two, the engine work will make the bike quicker. i got the idea from a few engine builders. i am not making anything up.

 

It scares me when people say it makes something quicker, I can make something quicker just buy changing a sprocket. The problem you run into is when boing internal mods without the complementing intake and exhaust mods is you are going to comprimise somewhere. If you put a higher lift and duration cam in without the other work you will most likely loose either top end or low end torque. Which will also happen with intake/exhaust changes but not as drastic. The other problem is raising the compression ratio will most of the time require you to upgrade your ignition besause it is harder to ignite the mixture in a higher compression engine. So what ends up happening is that you get a motor that may be more powerful it's not the most usefull power. You want the extra power to come on in the area where you do your most riding so unless you are drag racing only I would stick with moving more air. Just so you understand I have a 13:1 piston and a Stage two cam in my EX so I understand the bennifits they bring.

 

this is what we had:

10:1 406 wiseco piston, thin cosmetic head gasket, stage 1 hotcam, stock pipe, stock carb, rejetted


we have 3 400ex's. we have 4 pipes, a sparks x-4 ceramic, a sparks x-6 stainless steel that has been thermal coated, a full hmf pipe, and a big gun slip on. the bike with the 406 in was far superior to any of the other bikes in all conditions we tested. this was tight tracks, open tracks, and drag racing. we never tried putting around in trails at 2 mph or less, so i can't comment there. we are not big trail riders so that isn't a huge concern for us. however, it was great in trails if your were on it. yes, we all prefer the stage 2 due to OUR riding style but i wouldn't hesitate getting the stage 1 if i had a small bore or if i wanted a nice trail bike. i realize what type of riding you do has a lot to do with what mods you do to your bike.


as a matter of fact, this 406 hasn't been beat by any piped and jetted z400 or kfx yet. however, at very top end, the piped z400's are a bit quicker when the ex had a stock pipe on. then we put the x-4 on the 406 and it did indeed run much better, like we figured.