I am a fan of the Magazine due to the really good detailed tech articles it features. I was reading the Helpline page and noticed a fellow rider out of New York with a problem that I and other riders of the HD tour bikes have had for many years.
Mark Butler wrote that the 02 bike he had was doing a high speed wobble. Your answer covered only part of the problem. IF all of the things that you suggested were in spec, the bike would still have the same problem. The highspeed wobble has been denied by HD, investigated by NHTSA, and appears on most search engines of the web as a topic for a few lawyers. It also appears as a cause of death for some riders.
I own a small business that customizes bikes and found that the true issue is the law of physics as it applies to leverage. All riders know that the rear tire wears faster than the front. Most of this wear comes from friction. The friction comes from force applied to the tire.
What happens then is that the force acts as leverage on the swingarm and since the nearest motor mount is not until you get between the cylinders, then the drive line is allowed to move from side to side slightly.
I did not believe it made that much of a difference until I was at the 06 V-Twin show in Cincinnati and met the owner of True-Track. He had a FLH frame upside down in a press that simulated the force. I watched as the little movement at the motor mounts for the engine lead to a two inch side to side movement at the rear axle.
He had a device that is easily installed that makes a third link for the driveline. This is what Eric Beull explains in a patent for the isolated driveline that True-Track cites.
Of course, I try to test all performance items prior to giving my thumbs up. There were three problems that the FLHs have that I wanted to test for myself on a '99 FLHTPI that everything was checked to being in spec that you listed but still had the problem as well as one problem that a fellow had with cross wind and his 06 FLHTCUI right from the start.
1. the high speed wobble - Mine hit really bad when running 104 MPH. Sure that is extreme, but this is a police bike.
2. the wobble/sway from running through the twisties - I was being left behind by softails that have their swingarms tied to their frames unlike FLHs.
3. trailing a semi and overtaking without getting a wobble - Again, this was close to the same wobble that occurs at high speed, but was happening at 70 mph.
4. Cross wind causing poor handling - the fellow rider with his new 06 referred to his experience not as riding, but as trying to catch his bike.
I installed the true track and noticed that right off the road felt more stiff, knowing that the asphalt did not change. I knew that some side to side movement was gone. After getting used to this i ran the same tests.
1. High speed - nearly all gone. I have hit 104 a few times and will only get a slight wiggle from the front forks if I hit a rock or pothole while running that high. Just a pull back on the bars and it goes away without decelerating.
2. riding the twisties - I can canyon dive with the best of sport bikes now. Switching from side to side is crisp. I have installed a set of bronze bearings to replace the Cleve-blocs on the swing arm pivot axle and it made handling even better still.
3. following and passing semis - No problem. There is a little buffeting, but not anywhere near what it was before.
4. Cross wind - to duplicate my friend's bike I installed a full size tour pack and have ridden both with and without a passenger on 30 - 40 mph wind days without a problem.
So please pass this information on to Mr Butler and the rest of your readers. The contact number for true track is 818 623 0697.
I have also sent a copy of this email to True track so you will have their email as well.
Thanks for the great magazine,