Hmf Pipes

[397ccEX]

hEY I WANNA GET A PROCIRCUIT T4 OR AN HMF Full or slip on
Does the hmf lose power with quiet core?
If so would it lose so much power where t4 would be better?
Reason I ask is because i cant have a loud pipe
Pro circuit t4 is 95 Db
HMF FULL DB?
SLIP ON HMF DB?

[muddy400EX]

i think a t4 is way louder than 95db. i heard one on a raptor and it was louder than an hmf on a 400ex. and HMF is rated at 103 to 105 db.

[400sEXridr]

yes the hmf does lose a lot of power with the quiet core but it does make Mr. Ranger happy.

[Derag2]

how much power do you accually lose? I was gonna get aquiet core but now i don't know.

[LazeR]

I know from experience since i have the HMF Slip-On and i run the quiet core at the dunes....it makes a huge difference with sound but not that much on Power....you can actually barely feel it. I am very happy with my HMF

[397ccEX]

Ok so the hmf with a quiet core loses alot of power no use getting it because it cant be loud and I would have to use the quiet core is it loud with out quietcore full or slip on?

[Derag2]

From what i've seen you can't have an aftermarket pipe thats not loud..... There all pretty loud. So i think your stuck with having to get the quiet core.

[2001300exguy]

get the QRS (Quiet Race Series) its supposed to meet all restrictions and regulations

[Derag2]

i'm going to hijack your post again....... Would you have to rejet if you jetted for an HMF pipe without a quietcore and then put the core in? Or would it still be alright?

[LazeR]

Its still quite a bit louder than stock with the quiet core....im sure if you rejetted you could gain a tiny bit of power, but i don't really think it would be worth it! I don't rejet.

[397ccEX]

Well if i get hmf i will have too use quietcore
Or i could get procircuit t4 which ever has the most power
The main deal is the hmf must have a quiet core

unless theres any other pipes with great powergains and around that decibal

[Wayne64SS]

my HMF is loud as hell, so is my buddies on his 400ex. we dont run quiet cores i wanna hear em. sounds sweet goin down the trail. Neighbors hate us !!!! LoL great power i wouldn't buy anything else. Fit iand finish is A+ i say buy HMF but make sure you get full system.

[BigBadJ400EX]

Get the HMF with the q-core...You won't regret it.:D

[LazeR]

Originally posted by BigBadJ400EX
Get the HMF with the q-core...You won't regret it.:D


I couldnt agree more!!!!! :cool: :) :D

[YZ400EX]

I have had both the Pro Circuit T-4 and the HMF full systems and they are both very loud..I would say the HMF may be a bit louder, but to me definately a better exhuast. If you have to choose between the 2 systems go with the HMF. You will be much happier and is very easy to add or remove the quiet core when needed. HMF!!!

[SethSPST]

Where can I find an HMF? How much diiference will a slip on be from a full system on a stock motor?

[LazeR]

Originally posted by SethSPST
Where can I find an HMF? How much diiference will a slip on be from a full system on a stock motor?

C&D Racing the site sponsor, thats where i got mine and i highly recommend them, great service :)! I hear with a stock motor if you get a full system you can actually lose a lil bit of bottom end because you lose to much backpressure! I don't really know the whole truth to that! I just have a slip-on and love it, made a pretty big difference

[397ccEX]

Are you sure that you lose bottom end with a full?

[6858-400ex]

were and what is the best price for the hmf

[cals400ex]

the whole power band with the full hmf seems great. i wouldnt get just the slip on if it was me. maybe if your just interested in power for the first 3 gears or woods riding. i bet C&D will have the best prices.

[Jersey450R]

i got the slip on Elliptical series powdercoated black. ordered it straight from HMF. took 8 days to come in since they make all their pipes to order. great cumtomer service. the only difference between round and elliptical is the look and supposedly maked a more deeper tone. i love my slip on. kinda glad i didnt go with the full system. i got the pipe, powdercoat ($20), a jet, shippin for 265. thats Ohio to Jersey. Oh and they threw a free poster with it too. great pipe man, excellent performance gains and the sound is unmatched.

[2001400exrider]

I also want to get an HMF pipe...but not sure whether to go full system or not....Right on my stock header where it goes into the engine there is that dimmond shaped peaice and mine is like bent or warped. at this spot i can see exhaust leaking and can also smell it...did i blow a seal or somthing? is that dimond shaped peaice a seal?! I would like to get this sorted out before i order my HMF pipe...

[397ccEX]

I hear with a stock motor if you get a full system you can actually lose a lil bit of bottom end
That is not true Ive heard it from people but i dont think there is any truth to that statement

[speedracer400]

I just got my cdi and ballance pro slip-on in and on Friday. That romps now i wouldn't second guess stompin Z400's now. Quality of product and customer service for the money Hmf has the ticket. I did alot of reading nobody else seemed to produce that useable trail power. I got the quiet core with but I hope I never have to use it. But from what I've read its barely noticeable.Idon't think you can go wrong with hmf and i dont think you'll regret it.

Ballance pro even comes with a torque range modifier.

[Tortured Z]

I started with the slipon then after 3 weeks decided to buy the head pipe and make it a full system. I can't believe the difference, it's night and day. You lose nothing and gain alot, at least 1 to 2hp throughout the entire power band. I won't bother with a slipon again.

[2001400exrider]

Originally posted by Tortured Z
I started with the slipon then after 3 weeks decided to buy the head pipe and make it a full system. I can't believe the difference, it's night and day. You lose nothing and gain alot, at least 1 to 2hp throughout the entire power band. I won't bother with a slipon again.

ok but you have a Z? it should have the same effect the ex?

[Tortured Z]

I've heard the honda shows better results when uncorked.

Originally posted by Tortured Z
I've heard the honda shows better results when uncorked. iv'e heard the Z did

[Tortured Z]

I did some research and found they are real close to the same, the Z shows more improvement in the higher RPM's. Probaly because of the dual overhead cams. The EX shows slightly better in the midrange.

Hope this helps :D

[jetmec2k]

the post started out as the pro-circuit vs the hmf pipe......my friend already has a hmf on his "z" and i wanted the pro circuit full system for my 400ex..... but whats the big difference between these two pipes??? what one makes more power and where low end or high??whats so bad about the pro circuit??

[BamaRider]

As far as price goes, you won't beat Chaparral. $188.99 for the slip-on, & 386.99 for the full. They don't charge extra for the pc'd cans, plus free shipping. Best deal I could find on an HMF, and glad I did.:D Hope this helps.

[muddy400EX]

HMF is awesome. i didnt get the quiet core because i dont really wanna spend $30 just to lose power and make it sound worse:( i wanna hear the pipe, cuz i think it sounds awesome:D and really, its not that loud with a sparky in it(i run one) people who complain about the noise should just quit whining IMO

[2001400exrider]

All HMF's come with a spark arrestor right?

[muddy400EX]

Originally posted by 2001400exrider
All HMF's come with a spark arrestor right?


i think ya might have to ask for one when you order it online. i got mine from my closest dealer and luckily it came with it.

[MNTNMAN]

When I got the slip-on for the EX the spark arrestors werent USFS approved yet. I waited till they were. Since they weren't approved when I bought the pipe they sold me the quite core and SA for $15.

And there is no noticeble difference in power with or w/o the qutie core.

[2001400exrider]

and they quiet core is easy to put in and take out? does it make a GREAT differnce in sound?