Thanks for the info. Did you get an HMF header to go with the HMF exhaust? Not entirely sure if its necessary. Matasickle and other forum members have mentioned that it's not crucial. Also, did you install your Dynojet kit before installing the exhaust? I've read, and been told, that it's a good idea to install both at the same time.

 

Agreed. No point in relying on mechanics for everything. Would you happen to know any links to visual step-by-steps for Dynojet installs? Pretty sure I was looking at one earlier that was recommended by brutus5000. Here's the link.

Kawasaki KLX 250 slip on - HMF Engineering Forums

It's a pretty good guide, I think.

 

do the exhaust and dynojet at the same time.

 

Yeah, if you go under the sticky's up top, under FAQ's I think there are a couple of links to some write ups as well. Or you can always do a search on this site as well.

I looked at all those when I did mine but when I got out and did it, i found I really didn't need much help. It is pretty obvious what needs to be disconnected and what not. At first it can seem pretty intimidating because there are several vacuum lines and different emission lines, but if you just take your time it is really very simple. The hardest part for me was getting the carb back in. The rubber boots it connects to are kind of a pain. It just meant I had to try two or three times to get it seated correctly. Again, not rocket science, just take your time. The actual jetting only takes a few minutes.

 

^^^ what they said. Not very difficult. Take your time. Make some notes if you want. Maybe label the vacuum hoses and take some photos. You may not need the notes/photos in the end, but if you do, then you got them. Don't do it when you're in a hurry to go ride. I found the carb removal/install to be kind of difficult the first time, but the 2nd and 3rd times have been much easier!

 

Like others have said I think there is not a lot of difference between the different exhausts. One slip on will probably give you pretty much the same performance as another. Same with full exh vs full exh. But I would like to add the recomendation that if you get a full exh look for a header that has a heat shield where the OEM one was or get an aftermarket one. My leg gets hot when rideing the GF's bike which has no shield.

Cheers, Jim

 

Nice looking slip-on. Appreciate the links. Problem is I own a 2011 KLX250S, not a 2010. I've just finished sending emails to both HMF and FMF inquiring about compatibility issues, asking if there is a difference in manufacturing from 2010 and 2011 KLX models. Want to be sure that the slip-on, whether it be HMF or FMF, fits my 2011 KLX beforehand. Regarding the header, this afternoon an authorized Kawasaki mechanic told me that installing an aftermarket header, such as the FMF Powerbomb, wouldn't make a difference other than in tone. That's just what he said. He also said that a Kawasaki Pilot jet, a $30 part, would have the same affect as a Dynokit. By the way, Matasickle, did you purchase the HMF slip-on? Any trouble installing it?

 

Stay away from that mechanic. The Pilot jet should be about half that price. The Dynojet kit does NOT include a pilot jet - if you want to change the pilot, you need to order a Kawa part. There's no way a new pilot jet would do what a Dynojet kit does. The DJ kit includes a whole series of main jets and a new needle, and it's the needle that, IMO, is the most important part in their kit. I wouldn't expect the main jets to be any different in real performance between the Kawa part and the DJ part. But the main jet is very important for big power in that it performs at around 3/4 to wide open throttle. The pilot jet only really performs from idle to about 1/4 throttle.

 

I totally agree with these points. Much better to do the entire Dynojet kit mods.

I also feel the FMF headers help with improving flow, due to that they are slightly larger in diameter than stock.

 

For you guys with the HMF.. what are you getting for MPG now?
I think I just dropped to 55mpg..
Also, how many turns out on the fuel/air screw?
I have some annoying decel pop!