Dial-A-Jet - New Tech = New Attempt

The question - I see that you have and are using an EGT gauge to tell you how hot you are running while at speed. Have you ever used a devise called a "Dial-a-Jet"?? It allows you to adjust the main up or down 5 whole steps from your baseline jetting, from outside the carb. You just twist a knob. You can do the adjusting from the seat (with a little practice) and notice a change in temperature on the EGT right now. Now, we don't have one, so we don't know how it works in real life, but when you yank off the paddles for the run "south", the kit sounds like THE hot setup for quickly re-jetting and saving the motor.

The response - Actually I have used one - or something like that several years ago. I used to have one on a Honda Odyssey 250. It was a Mikuni version. What you did was put in a main jet about 10 sizes larger than the largest you'll need. Then the knob on the carb would meter the fuel from there. If you ran a cable to it in the right way and kept one eye on the EGT you could lean it out as you went down the straits, then turn it back when needed. I think it gets the job done, but in kind of a messy way. That is to say - I think standard jetting is much more accurate. I always buy genuine Keihin jets - NEVER use the generic ones! I think the same is true of the Mikuni parts. Why risk a several thousand dollar motor over a three dollar jet.

-I'll let those who don't know in on a little jetting secret - but they have to promise not to tell...

Jetting is NO BIG DEAL!!!!!!!!!!!!!

What is a big deal is all the rhetoric surrounding it! The most important thing to remember when jetting is that you're jetting your motor. Not a motor like your buddies or a friend of his. When jetting - only think about jetting. It's best not to make a run, have a sandwich, change a jet. Then make another run, chat with your friend, change a jet, drink a soda and eat some guacamole. Then "oops, did I change that jet... ummm larger or smaller."

Anything worth doing is worth doing right <- not my invention. Concentration will pay off. There is no mystery. A spark plug that's looks rich IS rich. A spark plug that looks lean IS lean. Get a loupe. A jewelers loupe. Pull the plug after one good plug chop on a clean plug and look at it. Read it where the ceramic meets the metal case. Not where the center electrode meets the ceramic. This is very old technology and is still relevant. The fastest engine tuners in the world still pull plugs and look at them.

The EGT is a gift and a time saver. A quick way if you will to get very close to ideal without looking at the plug. It aids in jetting - it does not replace looking at plugs. I still do plug chops. What changes is that when I do plug chops I can note the exhaust gas temperature and other variables. This is good technology. Once I have a baseline dialed in, I can change from there with complete confidence - (read - RAD).

On trips to Mexico or anywhere else stopping to change a main jet takes about 3 minutes on a TRX. I feel bad for those Banshee owners who have to take a roll away with them to change a jet - especially if they opted for the 35 mm PWK's. Not only does their motor burn fuel at a rate of 3 gallons to my 2 gallons, the overall power to weight ratio of their bike is LOWER! UGH!

Rick - see http://www.holtzmaneng.com/index.html for information using this jetting device, or check out the company whose product actually carries the Dial-A-Jet name - http://www.thunderproducts.com

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