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Mdkp123
06-24-2014, 09:27 PM
Just installed a full yoshimura rs2 exhaust on my 07 400ex. I also have a UNi filter and will most likely be ordering the ehs air box lid.
From what I gathered I should be a 42 pilot and around 170 main. I'm 600 feet above sea level.
Does that sound like a good size jet to start with?

I'll probably run no lid until I get my ehs lid in.
DragonGunner
06-25-2014, 01:59 PM
Just installed a full yoshimura rs2 exhaust on my 07 400ex. I also have a UNi filter and will most likely be ordering the ehs air box lid.
From what I gathered I should be a 42 pilot and around 170 main. I'm 600 feet above sea level.
Does that sound like a good size jet to start with?

I'll probably run no lid until I get my ehs lid in.


Sounds like a good start....I'm at 750' with 11:1, ported, k&N open box and run needle raised one notch, 42 pilot, 185 main.
Mdkp123
06-25-2014, 02:21 PM
Thanks for the reply. I just got back from my local dealer, they had a 165 main in stock so I'm going to try that out with a 42 pilot. I'm installing it in a little bit.
JOHNDOE83
06-25-2014, 03:12 PM
read "the process in detail" #4 is the most important one, needle is usually fine on 400exs and the pilot needs to be bumped to a 42.

Very helpful site http://www.jetsrus.com/FAQs/FAQ_rejetting_101_how_to_rejet.htm
Mdkp123
06-25-2014, 03:44 PM
Ok good info I read through it.
I have this chart that I have been going by
http://i1353.photobucket.com/albums/q676/mdsiman/Mobile%20Uploads/2014-04/B5A2C4EE-3348-41BD-9EB3-34248F4B643E_zpstyc66f7t.png (http://s1353.photobucket.com/user/mdsiman/media/Mobile%20Uploads/2014-04/B5A2C4EE-3348-41BD-9EB3-34248F4B643E_zpstyc66f7t.png.html)
Mdkp123
06-25-2014, 08:02 PM
read "the process in detail" #4 is the most important one, needle is usually fine on 400exs and the pilot needs to be bumped to a 42.

Very helpful site http://www.jetsrus.com/FAQs/FAQ_rejetting_101_how_to_rejet.htm

So I shouldn't mess with the needle at all?
DragonGunner
06-25-2014, 09:05 PM
[QUOTE=Mdkp123;4367845]So I shouldn't mess with the needle at all?[/QUOTE


You should be ok without messing with it, it will slightly richin it if you decide too. I did on mine because I got alot of airflow and it helped the throttle response.
Mdkp123
06-25-2014, 09:19 PM
Ok thanks. I guess I won't touch it and after I install the 165 main and 42 pilot ill see how it runs.
Mdkp123
06-26-2014, 06:47 PM
Installed 165 main 42 pilot and went 2.5 turns on a/f and it runs real well with the lid off. Tried it with the lid on too but it didn't ride as good. Def more power with the lid off too.
Thanks for all the inputs
Mdkp123
06-26-2014, 06:48 PM
Installed 165 main 42 pilot and went 2.5 turns on a/f and it runs real well with the lid off. Tried it with the lid on too but it didn't ride as good. Def more power with the lid off too.
Thanks for all the inputs