Full exhaust question...

[idro]

Hi I'm new, had my 400ex for little under a year now.

I want a new exhaust setup, and i was thinking about Yoshimura full exhaust setup. I've heard this on sport bikes and it sounds pretty sick.

Or would I feel decent gains with a slip on? A buddy of mine highly recomends a White Bros. slip on.

With the install is it pretty straight forward? Simple bolt off and bolt on process. I've done all the mods to my cars etc etc, so im pretty knowledgable with a wrench.

[zrpilot]

If you don't plan on further mods, a slip-on is a better dollar vs. performance gained. HMF is the best slip-on out there. The WB is good as well.

Just one note of caution, on my '05 400EX, Honda musta had some gorillas working the day they assemblied my quad as the exhaust flanges where so tight they bent the flanges and bent the 3 of the 4 exhaust header studs!! I actually had to cut the flanges off with a dremel and replace three of the four exhaust studs

Also do the job right and replace the exhaust gaskets when you put the new system on. They are copper colored and are sometimes hard to remove the old ones.

Lastly, don't forget to re-jet for the new flow. Probably 2-3 jets sizes bigger then you have now.

[†2005 400ex†]

Originally posted by zrpilot
If you don't plan on further mods, a slip-on is a better dollar vs. performance gained. HMF is the best slip-on out there. The WB is good as well.

Just one note of caution, on my '05 400EX, Honda musta had some gorillas working the day they assemblied my quad as the exhaust flanges where so tight they bent the flanges and bent the 3 of the 4 exhaust header studs!! I actually had to cut the flanges off with a dremel and replace three of the four exhaust studs

Also do the job right and replace the exhaust gaskets when you put the new system on. They are copper colored and are sometimes hard to remove the old ones.

Lastly, don't forget to re-jet for the new flow. Probably 2-3 jets sizes bigger then you have now.



i had the exact same problem, they were so tight i could barely get them loose using all my body weight, and when they did come loose they made that snapping sound, way too tight in my opinion.

[hornetgod13]

If you plan on doing future motor mods like a racing cam or bumping up the cylinder size than you would benefit from a full system. Expect to pay $450.00 to $750.00 for a full system.
If you just plan to run a hi-flow filter and air box mods than a slip-on is all you'll need. You still get the performance gains that will make you happy and they sound awesome. Expect to pay around $250.00 to $400.00 for a slip on.
I own a HMF slip-on and spent $269.00. I'm happy with it. It looks and sounds amazing! I just don't think spending an additional $200.00 on a header pipe is worth it.

[idro]

thanks for the replys, only mods i was going to go w/ was some form of exhaust, jet kit, and a new air filter.

This isnt going to be some kind of dynoqueen quad, just wanna bit more pep because i can't keep anything stock. :D

What is a good place to order exhausts from? And if i get a slip on, do i have to have the jet kit right after? Some posts i have read made it sound like i needed it with a exhaust and some didnt. That seems like a key thing to make the motor lean out and what not.

But since you guys said just a slip on for not a lot of mods i think i'll just look into a slip on. All I'm really going for is sound here. I just wanted a deep sound, not anything high and loud pitched.

[northwest Texas]

Just buy a few larger jets with the exhaust. Jet kits are a waste of money, been there done that.

[krt400ex]

Originally posted by †2005 400ex†
i had the exact same problem, they were so tight i could barely get them loose using all my body weight, and when they did come loose they made that snapping sound, way too tight in my opinion.

happened to me too...

[krt400ex]

Originally posted by northwest Texas
Just buy a few larger jets with the exhaust. Jet kits are a waste of money, been there done that.


agreed 100%

go with a 42 pilot, get a '04 or older needle and put it in the 2nd or third position, and a 152 or 155 main...IMO i would at least cuz some holes in the top of the airbox and jet it to a 155...much better power.

and personally, the yoshi full system is the best u can buy...and there is a difference between the s/o and full system....i would definatly get the full system

[krt400ex]

Originally posted by hornetgod13
If you plan on doing future motor mods like a racing cam or bumping up the cylinder size than you would benefit from a full system. Expect to pay $450.00 to $750.00 for a full system.
.


at this site (http://rockymountainatv.com) u will find full systems for lower than $450...the yosh full system is only $400

[hornetgod13]

I'm not a yosh fan myself but, I guess a full system for around $405.00 is a good price. I just don't see any since in paying a lot more for a header pipe if I don't plan to do any motor mods.
Stick with keihin jets. You can buy them individually and you should only need 2 or 3 to jet your quad accurately. You can buy them at www.jetsrus.com
With your airbox lid on I would go with a 152K or 155K. With the airbox lid off I would bump it up to a 158K or 160K.
Here's a video clip of my HMF Slip-on. You can hear what it sounds like. This is with a quiet core installed which can be removed.
http://media.putfile.com/400EX-HMF-Slip-On-

[johnsls]

You can buy the slipon on here from Colby @ CDRacing

At the time I bought mine I got it on ebay,, the guy ended up being cool and sold me the sport series (not painted) and the Quiet core for $225 or $230 shipped.

Colby can also hook you up with the jets you need too :D

[idro]

Originally posted by hornetgod13
I'm not a yosh fan myself but, I guess a full system for around $405.00 is a good price. I just don't see any since in paying a lot more for a header pipe if I don't plan to do any motor mods.
Stick with keihin jets. You can buy them individually and you should only need 2 or 3 to jet your quad accurately. You can buy them at www.jetsrus.com
With your airbox lid on I would go with a 152K or 155K. With the airbox lid off I would bump it up to a 158K or 160K.
Here's a video clip of my HMF Slip-on. You can hear what it sounds like. This is with a quiet core installed which can be removed.
http://media.putfile.com/400EX-HMF-Slip-On-

that sounds pretty dang good, i think i'll go w/ that HMF pipe.

[j450rking]

you can get a yosh full system for $360 at moto sport or a slip on for $260 eather way it's a good deal