Or consider the Dial-A-Jet which can easily compensate for the lean jetting. Contact Phil at Thunder Products and talk it over with him. There are a lot of ATVs and snowmobiles using the product in exactly that way. There are owner testimonials and media comments about it. Saves tearing down a bike to jet the carb when going through a 6000 foot elevation change.

Here's a few from their page:

"I just followed the simple directions for installation. We rode in New Mexico, Colorado, Wyoming and Utah reaching altitudes as high as 12,000 '. The Dial-A-jet worked great! I had all the power I wanted all the time. I would highly recommend this product to anyone with a carbureted engine."
Chuck Whittle Travelers Rest, SC

"We are very happy with our Dial-A-Jets and TPI Valves. We ride from 300' to 11,000'."
Dwayne Farmer

It appears their media page isn't functioning.

 

We really need folks like tim - who ride a wide range of altitudes - to try the Dial-A-Jet..

 

Hey Guys,

I will read up on Dial-a-jet, but this does bring up a reason why, I personally, will probably not to tune to the ragged edge at a given elevation. My setup prior to the MCM was with the DJ kit and their 128 main, it ran pretty good most of the time and just "OK" at altitude. But it did run "ok" at altitude!

Don't get me wrong, I appreciate Klxster's efforts to dyno tune and share maximized jetting at a given range near sea level. That is awesome! I'd be all over that if I my riding stayed within a particular range of elevation. Absent the Dial-a-jet, I believe I am forced to compromise a little to be able to at least run OK at the elevation extremes.

The MCM surely opens the door to a lot more power potential and I fully understand if some question why I am not taking full advantage of that with fine tuning. However, the riding I chose to do involves a range of elevation.

I'll be bumping up in main size and watching as I go... perhaps working my way towards, but probably stopping shy of the magic 144/1N combo!!!

This is a great forum and i appreciate the info sharing that goes on! I have not had a chance to do any further riding or tuning, but will surely (Shirley, for you Airplane fans) install the DJ132 that came in my kit before the weekend... then look into ordering some larger jets to try out!

Oh, to have some free time to look into Dial-a-jet....

Take care guys!
TC

 

Gotta say there are a lot of ATV and snowmobile sites with postings on using the Dial-A-Jet over multiple jetting changing as well as riding over a broad range of elevation. So it ain't breaking any new ground. The Dial-A-Jet has been around doing what it does since the early 80s. If it didn't work it'd be long gone and I would never have bought three more over the years, giving one to my brother.

It is hardly tuning to the ragged edge. It is simply jetting for the high elevation, then relying on the fuel adder to add the extra fuel at low elevation. Actually on my 650 it was apparently lean enough to run cleanly at around 4000-5000 feet in West Virginia, then run cleanly at sea level in Daytona courtesy of the Dial-A-Jet.

Read up and call Phil at Thunder Products to learn more.

 

Read up. Will do. I had a neighbor who was into sleds and I think he said his Polaris had some type of automatic compensation for altitude???

I probably should not have used the words "ragged edge." I suppose the ideal situation is to have the an optimized tune for where you ride the most and then have a way to easily compensate for elevation (Dial-a-jet), otherwise we chose between changing jets along the way (yuck) or running a compromised tune somewhere in the middle of what works best at the ends of your riding spectrum.

My former DJ Stage 2 setup ran "pretty good" most of the time and "ok" at elevation. I'll be trying out the 132 main with the MCM this weekend, it is the only jet I have larger than the 128 I had been running.

Thanks!

TC

 

You just want to lean it out until it runs decent at the higher elevation, then install the DAJ, but I'd still contact them by phone. I've been saying Phil, but it might be Lon that you want to ask about how to set up as you want.

 

Cam mod...stay on topic.

 

For those considering doing this mod. You don't have to press the KACR off, reposition it, and press it back on. The best solution is to press it off and throw it in the trash. Second best would be to disable it by removing the spring. Personally I thing the bike has never run better with it gone. Engine starts are super fast. My bike will start when cold as soon as it hits the first compression cycle. I know some people didn't do the MCM because they where intimidated with the thought of retiming the KACR. You now have no excuse in not doing the mod.

 

Agreed, I just disabled mine with a piece of welding rod. Starts much easier for sure... Be warned though, if you don't have a healthy battery you'll kill it pretty quickly as it has to work much harder to turn that starter afterwards.

 

I really didn't notice the starter turning over any slower after the removal.