dynajet with hi-flow end cap

[satrx]

I am going to rejet my 400 because I'm taking the airlid off. I've got a stock exhaust, but I replaced the stock spark arrestor and exhaust tip with a hi-flow exhaust tip. Should I jet it for a stock exhaust or an aftermarket exhaust?

[exrider008]

first off welcome to the site. dont quote me on this but, yes u should rejet to an aftermarket exhaust because u have no lid.

[GPracer2500]

You'll likely be closer to an aftermarket exhaust than stock. I wouldn't think of it like "which pipe should I jet for?". Instead, jet your bike with whatever IT requires and for your climate and elevation.

[satrx]

thx for the quick responses and the welcome. This is a great and informative site that has helped me a lot in my lurking.
The kit has two different sets of instructions, one for lid-on and one for lid-off. So I'm using the instructions for lid-off (actually I have a K&N powerlid and filter). But then it breaks it down into one jet for stock exhaust and another for aftermarket. I'll start w/ the one recommended for aftermarket and see how it runs.
thanks

[04'400ex'er]

Go ahead and jet for the aftermarket exhaust. If you have the powerlid on with the stock exhaust, and you jet for an aftermarket exhaust with the lid removed, you are gonna end up rich. Your just gonna have to play with it a little. Worst case scenerio you will be rich. but better safe than sorry right?;)

[NCexRider]

You should jet it as a stage 2 (no airbox lid) with STOCK exhaust, because that's exactly what you're running. That tip really doesn't increase flow. According to DynOjet you should be running a 165 main below 3000 feet, 160 from 3000 to 6000, and a 155 above 6000 with the needle on groove 3.