I've got a 2000 Road* with about 35,000 miles. I do a lot of endurance riding at 80-85 MPH and was disappointed with the 32 MPG I was getting at these speeds. After reading many of the posts here and at the RSR Forum, I determined the dealer did not have the jetting tuned correctly, so I started playing with it myself.

Where I started:
Cobra Lo-boy Shotguns
Barons BAK
Stock Manifold
AIS Installed
Pilot Jet: 35; Main Jet: 170; Needle: 5th clip; PMS: 3.5 tutns
Required Choke to start

Besides the poor milage, I was getting a slight gurgling sound at WOT (followed by the smell of fuel), pipes were dark black and I was having backfiring at altitudes over 6000' (I live at 900'. I was never terribly disappointed with the performance; I just thought I could do better.

I was told to remove the AIS for the backfiring. I adjusted the PMS to 3 and tested the fourth and third clip positions. Again, not bad performance, but still had the gurgling at WOT. I decided to switch to the 165 Main jet and put the needle back on 5.

Where I am today:
Cobra Lo-boy Shotguns
Barons BAK
Stock Manifold
AIS Removed
Pilot Jet: 35; Main Jet: 165; Needle: 5th clip; PMS: 3 tutns
Requires Choke to start

The milage has gone up to 38 on my last tank of mixed riding (half 55-65 and half 65-75) I am concerned about going too lean and harming the engine which the dealer tells me I'm doing by decreasing the main jet. The WOT test says I'm not too lean (assuming I'm doing it properly). The gurgling has turned into a nice snap. Performance is about as good as I've had so far.

How can I tell if I'm too lean. What are the symptoms I can look for before it's too late.

My gut sense tells me that your main is too small VTD.

But evry one of these bikes is a little different. If your bike is running too lean you will have a lot of heat coming off the engine, and it may tend to sputter out at higher speeds, kind of like it just can't come up with the power it should.

But there is a point of leanness that will provide great performance, and still be too lean.

I would really recommend that you find a Dyno station that can read your air fuel ratio for you during the test. Its one of the best ways to see how your air fuel mix is doing. At that point you will know where in the RPM range you may be too lean.

You might find out that you are dead on. If not, you will know where you need to make a change.

GRAM