Hey, I took my KLX to North Georgia mountains today; back roads and gravel roads with a little 2-lane highway. Wow, she runs sweet now, with Distanzia's, 13/48 sprockets, and HMF slip-on. I'm thinking about getting the recommended jetting done for the HMF, but I'm concerned about overall reliability of starting/running of the bike. She starts and runs absolutely perfectly, and I don't want to introduce any "gremlins" with what appears to be the "black art" of re-jetting.

Opinions? Is it worth the "risk" to make her run a little better? Is re-jetting with the HMF a big diff in power/response?

Thanx, Lance

 

Rejetting if anything will make it start easier and run better, so long as you don't overdo it. From the factory the bike is running lean for most conditions, except mountain running where the air is thinner anyway. By adding the aftermarket exhaust you've made the bike leaner by allowing the exhaust to escape more quickly and in turn should give it more fuel as more air can flow. But being in the mountains it "may" be ok as is. You essentially need to jet it for where you will spend the majority of your time riding. Deej has a great big main jet in his bike and it runs great in his home town, he took it up into the mountains and it wasn't running the greatest due to being too rich.

 

I live in Utah, at about 5000 elevation. I ride up to around 10k at times. The stock setup worked fine for me, but as stated, the bike is running in the lean side from the factory. If you have opened it up at all, I'd definitely consider the jetting. Running a little rich is safe, too lean can be bad. Check your plug to see how things are. But, really, you should just do some airbox mods/get a hi flow filter to get more air in, and then with the exhaust allowing more out, you will need the extra gas. You will also have a bike that is much more powerful

Carb setup/mods/details about reading the plug...

http://www.factorypro.com/tech_tunin...m_engines.html
http://www.hmfengineering.com/forums...ghlight=remove

 

I rejetted, even in the high altitude. Made my bike sound a lot healthier, and start easier when the temperature drops. Worth the risk? Too risky to not do it !

I could probably lean it back out a bit, but its running strong really good as is.