I have been riding 2 strokes my whole life(250r & LT250r). I just got a 400ex last fall and I love the thing but I miss the quick throttle response of a 2 stroke. The 400ex has plenty of power when you rev it out but it takes too long to get to that power.
I am looking for a mod. that will give me a quicker throttle response. What is best CAM? PIPE? CARB? or 440 kit.
My 400 is bone stock. I don't think I want a 440 kit. But what about a cam or pipe and by who? Thanks.

 

I have had my 400 EX a short time. But once I get something, I read every possible thing I can gat my hands on about it.

From what I've heard, throwing in a stock XR400 cam will do wonders.

I've heard that 440 kits will make your motor trouble prone.

Add a high flow air filter.

I bought mine used, it came with a Curtis Sparks pipe on it. It literally blows the doors off of my buddies (more than 1) stock bikes.

Adjust your throttle correctly. It comes adjusted wrong from the factory, and there is still some stock get up and go left in the adjustment.

 

A slip-on pipe, no airbox lid, an a XR400 cam should give you what you're after.

 

Where can I get a XR400 cam and how much?

 

You can either go to www.servicehonda.com or www.marcumsatv.com


Marcums is extremely helpful, and friendly, and competetively priced.

They even have a complete microfische of the 400EX online.

 

It depends on what you want to spend.First get the pipe and filter.If that doesn't suit your needs, get the cam and piston. After that I'd say the carb would be the next step.

 

iI drop my front sprocket down to a 14 tooth. It help me a lot. The
best pipe only give about a 1.5 horse power