Exhaust shootout

[allhondaman]

im new to quads really and i want to find a good pipe for my 400ex. I really want a pipe that performs great like the hmf, but i just cant have one that loud. I was lookin toward yoshi or this new pipe out called a Lexx. has anyone had one of these lexx pipes? ive heard they got good ratings and they cheap ($200). Also one of my friends has a WB e series and loves it and told me to buy one. are they a good pipe also? thanks for any info :D

[07trx400ex]

While we are on this subject, does anyone know if any of the brands have equal length head pipes?

[oleboy87]

well i read good things about a lexx on here but i dont know how loud is.. but i think you can get a fmf quietcore because they are not loud at all but my Buddie has a yoshi and its as loud as my hmf before i got the fmf powerbomb header which by the way is interchangeable with other brands because it is the same size as the stock header... but my hmf/fmf combo ha a great sound! its not near as loud as an hmf with just the quiet core and a stock header or even the hmf header.. and i think it has great gains but others will probably tell you diff

[allhondaman]

that combo sounds good. the power of the hmf without being overpowering loud like they usually are. I was thinking about the powerbomb...i guess it makes any exhaust quite huh? i guess i got to save up about 450 to get a powerbomb and hmf muffler. anyone know where i can get some deals on these? i know on ebay u can get a hmf for 200-230 brand new without problem.

[allhondaman]

are you sure that the powerbomb with the hmf is quiet? cause i dont think anything would make the hmf quiet lol. i just dont want to get get caught since i mainly ride dirt roads to get places. thats why i was looking into the WB e series or that lexx pipe.

The power bomb makes it slightly lower sounding they say 1.5dB lower and the exhaust has a bit better flow and obviously looks better. Then you could get a quiet core and it sould be much quieter. Keep an eye out for stuff on here. I got my HMF slip on with a quiet core for $135 shipped to my door. I also have seen a few powerbomb headers for the 400ex going for $100.

[400ex28]

Good luck finding an exhaust as quiet as you want.

[scuzz]

HMF comes with an additional silencer.

You could remove the silencer when you want to woop ***.

[shadowwalker]

Originally posted by scuzz
HMF comes with an additional silencer.

You could remove the silencer when you want to woop ***.
wanna know how well it works? Let's just say when I installed my Ballance pro full system, I thought the quiet core was out. Turns out it was already installed. I am actually concerned I won't be able to race, even with the core in.

Originally posted by shadowwalker
wanna know how well it works? Let's just say when I installed my Ballance pro full system, I thought the quiet core was out. Turns out it was already installed. I am actually concerned I won't be able to race, even with the core in.

I'm not possitive but I think you are mistaking the TRM Core (torque range modifying core) to be a quiet core. The Ballance Series have a different core that is supposed to make more torque or something. The Quiet core is something completely different that cost an additional $20.

[scuzz]

Originally posted by FoxHondaRider
I'm not possitive but I think you are mistaking the TRM Core (torque range modifying core) to be a quiet core. The Ballance Series have a different core that is supposed to make more torque or something. The Quiet core is something completely different that cost an additional $20.


Bingo!

[07trx400ex]

Does anyone know if their is an exhaust with equal length headers?

[oleboy87]

i think the powerbomb is the same size as the stock header

[07trx400ex]

There are two exhaust ports for the exhaust to come out of, when you look at a 400ex exhaust there are 2 pipes that merge into 1.

I am asking if, on any brand......

Are the two tubes coming out of the two exhaust ports are equal in length and diameter before they merge at the "Y"?

[XXXRACER165]

No there not supose to be equal in length. One port is supossed to be longer so when the pulse comes out of one port, it helps suck the rest of the exhaust out the other port. Called SCAVENGING

[TRXRacer1]

I recently installed a Lexx on my neighbors 450r and I am very impressed with them. For the price you can't go wrong. It comes with a quiet core in it already that sounds great and you can take the core out for a sound that will wake up the neighborhood. Fit and quality was good too. I just got an email from RMATV about WB pipes on clearnece if you're into them. I think they are on the main page.

[XXXRACER165]

The DR Fatboy4

[07trx400ex]

The Duncan Racing Fatboy 4 headers are not the same length. Whoever told you this is wrong.

Look at step #5 on the instillation instructons

Quote "5. Install header in right exhaust port and hand tighten nuts. * Right header has a
Tighter bend coming out of cylinder head and is slightly longer."


Look it up it is step 5 on the mounting instructions.
Here's a link: http://www.duncanracing.com/techfaq/Install_fat-boy-4-complete-exhaust-system-honda-400-ex.phtml

[oleboy87]

i dont know if ive ever seen one like you are looking for... im jsut wondering what is it you have agains the headers that are longer one side?

[07trx400ex]

There is nothing wrong with them, but anytime a "scavenging" effect is created by two unequal lengths then back pressure is increased, requiring more work from the engine. Also, scavenging creates a "spike" in the powerband at a certain rpm. I don't think this is necessary on 397cc engine and just wanted to know if there is any brand that uses the "equal length headers." If not, I would like to know why not, because that means I am approaching this the wrong way.

[shadowwalker]

Originally posted by FoxHondaRider
I'm not possitive but I think you are mistaking the TRM Core (torque range modifying core) to be a quiet core. The Ballance Series have a different core that is supposed to make more torque or something. The Quiet core is something completely different that cost an additional $20.
I'm well aware of this. I bought it used, and it had both the TRM and the Quiet Core. I thought the quiet core was what was in the box, however it was infact the TRM. The Quiet Core was in the pipe already. Because I went to put what I thought was the quiet core in, and to my surprise it was already in. They look completely different, but I didn't know what each looked like until I discovered the Quiet Core was already installed, and it was loud as hell.:eek:

[Hondamaster5505]

Originally posted by 07trx400ex
XXXRacer, I did not need a lesson on scavenging( and to be technical, it actually only happens inside "scavenging" rpm range, and the the exiting gas actually creates a vacuum for only part of the stoke, which, in turn provides the "boost" in power and torque. That is actually scavenging. To be even more technical you would want an exhaust speed between 240-260f/s and it is this way that you can determine what diameter pipe is best for your engine.

Since we cleared that up, I am still wanting to know if there are any pipes that do, in fact, have 2 equal length pipes until the "Y" merge.

DMC Alien:D

Instead of having 2 pipes merge to one, its dual headers all the way back to the muffler. Which im sure you know gets rid of the "lean condition" and also I think makes GREAT power gains.

They're hard to find though...:(

[07trx400ex]

Yeah, that should work, as long as it does not have any sharp bends(also creates back pressure). It is probably a little goofy to analyze something like an exhaust like this but it is fun.

I guess the alternative to the traditional systems are either the DMC Alien or LTE Duals, I am not familiar with alot of aftermarket companies for quads, so I am probably missing a few.

I should also look more closely at the stock system, from earlier experience it looked ok except for the sharp bend at the "Y", which looked very restrictive.

[allhondaman]

yeah for $200 the lexx sounds great. i think thats what ill go with since im short on the cash side. ill probably buy a powerbomb when i have my engine rebuilt (hopefully not anytime soon) and ill also have the head ported and polished and throw in a stage 1 or 2 cam while its all apart.

[allhondaman]

anyone know of a good place to order an exhaust besides ebay or rocky mount atv? (which is awesome in my experience)

[NJ450rider]

I have an HMF sport series with a quietcore in as well. That thing is still really loud and no where near 96 dbs like hmf claims. Id say its more like 98 to 100dbs still.

I have the HMF quiet race series full exhaust on my 450r. Its a huge difference in how much more quiet it is compaired to the sport series slipon on my 400ex.

[allhondaman]

yeah but how much does that quite core rob of performance?

[oleboy87]

you are not going to be able to tell the difference whether its in out

[shadowwalker]

Originally posted by allhondaman
anyone know of a good place to order an exhaust besides ebay or rocky mount atv? (which is awesome in my experience)

The newest issue of dirtwheels had a $20 off a purchase of 150 or more coupon for rockymountainatv.com in it. In case you're interested.