Modification questions

[Hotshoe18]

Ok, heres my question. If I were to take off the airbox lid and gut the stock pipe, would I have to re-jet? Also, what kind of power diffrence would I be looking at? Lastly, how exactly do I "Gut" the pipe? Do i just take off the endcap or knock out the baffles and re-insert the endcap or what? Thanks in advance

[drzoo2]

I can't answer your question about the pipe. The airbox lid is an awesome mod and YOU WILL have to re-jet. Take it off. The bike will idle but won't run past quarter throttle. Stock is a 130 and you'll need at least a 155 or more depending on elevation.

z

[Hotshoe18]

WOW, that mod must give it alot more get-go HAHA. Thanks for the info!

[mojavedude]

with gutting the stock pipe your looking at more torque with the stock head pipe or so they say over at z400 central. theres a few ways to do it but i would go with completely gutting the thing, by taking out baffles and geting a core some how, possably from a car exhaust or something and putting some packing materal in it. i know some companies make cores like big gun so check them out and look around. buy doing this, its close to an aftermarket pipe so you know you should be getting some performance out of it. you should re-jet with it. id go up as much as an aftermarket slip-on pipe goes up.

heres a few topics on it
topic 1 (http://www.z400central.com/invision/index.php?showtopic=10060&hl=$10.99+exhaust)
topic 2 (http://www.z400central.com/invision/index.php?showtopic=64898&hl=stock+silencer)

id like to try this when i get a z400

[drzoo2]

Originally posted by Hotshoe18
WOW, that mod must give it alot more get-go HAHA. Thanks for the info!

Cheapest mod I have done.......All my buddies were impressed and did it with their quads.

[Vindex Injuriae]

As they said above, you'll definitely have to re-jet, but it is worth it.

[mojavedude]

if i was you i would at least put some screen over the holes to keep large chunks of mud out. if you get what i had, it would work great. it was a vent sort of thing for a house and i took it apart by un folding the medal around it and i put in a layer of air conditioning foam filter. they just pop right in a hole and you can always take them out with no damage done. it kept dirt out. it really kept the filter clean. i think they come in 1'' or 2'' or around there from a hardware store.
heres some pictures of the things
here (http://i12.photobucket.com/albums/a244/mojavedude250/none003.jpg) and here (http://i12.photobucket.com/albums/a244/mojavedude250/none004.jpg)

[drzoo2]

I used the K&N power lid kit. Comes with a 155 and a 160 jet. I bought it cause I got a good deal on it. $50 off eBay. Normally around 80 or so.

z

[jherbie28]

are you against an aftermarket exhaust? you will put out some money but you will get the power you are looking for. also just my opinion but the stock exhaust with the baffle taken out sounds like crap. i also heard that when you take your baffle out something about backpressure, is lost.

[Hotshoe18]

Yes, I figured some backpressure would be lost... This is just something I was going to do while waiting to get my aftermarket exhaust. I'm looking at an LRD, I heard it gives great bottom end.

[JAYKNIGHT]

dont gut the stock pipe i did that to mine and it sounded like crap, way to loud which draws unwanted attention and gets riding spots shut down and the power gain wasnt that good save up some money and get an aftermarket pipe

[mojavedude]

im not against aftermarket pipes but there so expensive. a gutted stocker with a core and packing is similar to an hmf. im sure theres ways of making a quiet core too. plus i would do it because some poeple who did it said it added more torque and id rather had some nice torque then top end power. i ride trails and with my mojave i almost never bring it past 6000rpm not to mention a 400 already has more than enough top end.

[jherbie28]

hotshoe18 the lrd exhaust is great, not sure what you got going on with your quad but i have alot of upgrades motorwise and the exhaust is amazing pulls hard and sounds great. has kind of a huge muffler and only one attachment point to the subframe is the only down fall

[mojavedude]

Originally posted by my88r
you can just buy a slip on gutting the pipe wont do nothing just make it loud

gutting the pipe means taking everything out so its empty all the way threw, then putting packing in and a core so its just like an aftermarket pipe or hmf. this would be amost exactly like a hmf only the length and diameter of the core maybe. dont forget i have nothing against aftermarket pipes, hmf makes some nice stuff but spending $250 for a slip on is alot and id rather try making my own first.