Okay everyone, here is the deal:

Last summer I bought a 2003 400ex. I love it, but it is time to do some mods. I do not plan on doing any huge engine work, and I just want something that will make my quad a little more sick. I am looking at the white bros. e series slip (is the slip allright for me, or should I buy the full exhaust?) and I am purchasing a K & N air filter. As you all can tell, I dont know much about this mod game, so if you could answer my questions, I would be so appreciative! I just use the bike for fun, its a good sand toy.

I am also considering a CDI box. Someone told me not to waste my $$ since I am not doing any engine work. Is this true? Or will it give me that extra something. Is it BAD for the quad to have one if the engine is stock?????

Thank you all!

Meagan

 

The one who said you would not need a CDI box without engine mods was right. If you're adding a slip on muffler and an air filter, you will be okay without a new ignition. I would not recommend a new ignition unless you plan on changing the cam, valves, and springs. There is a reason the stock ignition is limited, the valve train was not designed for anything about this limit.

If you are planning on some agressive trail riding and sport riding, and maybe an occasional race, I would go with a slip on muffler (white bros. is fine), the K&N filter, and a jet kit to match. Leave the CDI alone unless you are going into the motor.

 

Thank you for the info. Time to buy the exhaust! Now I will not waste my $$ on the cdi box...I don't want to ruin the engine w/a mod that won't help too much!

Meagan

 

Glad to help you out. Enjoy your new upgrade ! ! !

 

i would consider the hmf pipes if you only want a slip on. they seem to make good quality pipes. the tone definately gives the bike some bark. i would even consider their complete system. i actually run sparks x-6 and my friend runs sparks x-4 and we both like our pipes.

 

Meagalo-I see that you live in oregon as my wife and i do and if you ride the oregon dunes you will probably want to take into consideration the decibel levels that are required(93 DECIBELS) or at least get a pipe that is somewhat close to that.My wife has a 440 ex and she uses a fmf-q muffler which makes very good power for dune riding which means it builds good midrange power so that may be one to look into.The fmf-q that my wife uses was tested at 90 or 91 decibels by the forest service at the dunes so it is very quiet for an aftermarket exhaust.The cdi will not give you much if any benefit if you are only going to put a pipe on and change your air filter and just in case you dont know you will have to change the jetting on your ex to accommodate the new air filter and pipe but it is a very easy job on the ex.

 

Thank You. I knew Oregon had requirements governing that; I wasnt sure what they were. Thanks![img]i/expressions/face-icon-small-smile.gif[/img]

 

There are plenty of slip on pipes. Alba and HMF both make good slip on pipes. Unless you have a DB limit. Then you would have to purchase the quiet core insert.

 

Hey Megan!

I used to live in Oregon, and still plan on riding both Florence and Sand Lake occasionally, even though it's a bit of a drive for me. I love it over there!

Check these links out. The first one is the home page for the Oregon Off Highway Vehicles Associaton. The second one is a link to the dB tests that the forest service has done on various pipes out on the dunes.

Oregon Off Highway Vehicles Association

Sound Issues

 

i would go for the Big Gun,a friend of mine has a slipon on his 400ex and i like it,i have a full e-series on my 300ex and it is a great exhaust too,it gave tons of low-end and midrange power.as for the cdi i have no clue