HMF Pipe?
I have the 09 KLX250S.

I saw a post by Drewski
06 KLX250s, HMF slip-on, 2.5 turns on fuel screw, 125 main jet, 40 pilot, 7/64 drilled slide, .032 shim on needle, no snorkle

How did the HMF work out?
Did you run with the quite core installed?
What is a .032 shim on the needle mean?

2.5 turns. is that all the way in then out 2.5 turns?

Any body else have any thing to add? I am thinking about getting the Pipe but also concerned about departing from the stock setup.

Any words of encouragement?
Thanks, Chris

 

Great Post. Thanks fo the info.
Do you like the difference the HMF made or would you hit the "undo" button if you could?
The link that provides the hpotos and step by step How-to is awesome.
Do you have a picture of the Drilled Slide air-hole?
I have read many o' posts that Drill "it" out but what does drilling that out do?

Thanks! Chris

 

Hatchetman and SlapDrum,, I would like to welcome you both to KF,,, I wish I could answer your question but im still currently running my stock can. as far as your A/F screw yes you go all the way in then 3 or 2.5 turns out from all the way seated,, but it varies on elevation so experiment with the screw and see whats best for your bike

 

I'm Running the HMF with the quiet core insert and the settings indicated below. I also have a 100% stock bike and the modified definitely pulls stronger to higher RPM and is reasonably loud -I did post the sound level data for the stock, Vs with HMF Vs HMF with QC insert.
Hope this helps

 

I've been looking at an aftermarket exhaust to install for a winter project. The HMF is at the top of my list- the link on the HMF forums is very informative and it looks like they did their homework on dyno tuning the bike.

http://hmfengineering.com/forums/showthread.php?t=1617

I'd be ordering the recommended jets and doing the mods to HMF's specs.

 

I'm also running a similar setup for over a year and a half and couldn't be happier with the HMF!

 

I have the 09 with the 06 HMF

You will burn your signal light off in 1 mile....Pipe sits alot higher then a stocker...Also Im running a jet kit and had a 13t....+>BlaBlaBla....

Sure it frees up some power and probably the best overall mod Ive done but its just too dang loud......Im almost ready to put the stocker on so I can run my choke without feeling like a bung......Or blowing done streets late at night in stealth mode.......

Rocco

 

Rocco,

Thanks. This post is very helpful. I casts doubt but I am reluctant to deviate from stock.

All,
I was thiking about buying an additional stock pipe and doing the 1/2 Drill trick. Is that a waste of time and money?
Anybody have a feel or guess for the power trade off.

Example: HMF adds 2hp and the Stock with a 1/2" holes adds .00001 hp

Anybody wanna try a more serious guess?
Thanks, Chris

 

If u r reluctant to deviate from stock then don't drill. If the Exhaust is going to burn your signal light off then don't buy it or remove your signal light before you install it. I suppose the 09's could be different than my 07 in exhaust set-up. If so then nothing I had posted would refer to the '09's.

 

I've been running the HMF since summer of 06. (I believe I was one of the first to get one)
Anyway, I'm very happy with it's performance but even with the quiet core was a bit load for my taste.
What I did was modify the quiet core by welding a plug on the inlet side of the core and drilling a number of small holes (to match the diameter of the core outlet) around the core tube. This is common practice in exhaust systems to control the attenuation of the exhaust note yet allowing flow. It worked out really well. The bike has a nice note w/o the rap.
Also added the FMF stainless head pipe.
IMO- it's an almost perfect set-up for the 250.
DJF