I see that Rocky Mountain has these and Outerwears in stock. Anybody running one? They say it works with the stock airbox.

I have the HRC kit, and will need to keep the stock header and muffler for a while. What jetting changes did you do???

 

You will have to trim or pull the breather tube out of the airbox a little untill the k&n fits. Jetting with the hrc should be 185 main, new needle 3 from top clip. That will come with the hrc kit and should put you in the ballpark. Your jetting will very depending on altitude and mods.

 

I just put a K&N on my trx450, haven't ridden yet. It is the same model as on a 400ex, and there isn't anything to keep it from working loose- I'll be fabricating something for this. Also, the breater tube was being filtered by the stock air filter, so I'm thinking to find a small filter for it as well.

 

Not sure why they did the breather tube that way? On the 400EX/300EX, the breather is inside the air intake boot. On all my other bikes, where the breather tube is external, there is always some oil getting onto the outerwears.

If it is the same filter as the 400EX, I have those already. I do like how the EX has that support underneath the filter to hold it up. Not sure I trust it without one.

sandman-My HRC is already installed, so what I was wondering is what change there would be beyond that. Those wire inserts in the stock Honda filters seem pretty restrictive, so I am guessing that there will be at least some jetting changes necessary with the K&N filter change.

 

I'm running the sparks filter and pipe. Sparks told me that the oem filter was restrictive and that his flowed much better. I really thought it was just a way to get a little more $$ out of me but after comparing the two I'm sure he is rght. I ended up with a 190 main jet 3down on the needle with pipe and filter.