I finally got my bike back after about 16 days of it occupying space at J&D Custom Cycles in Morrisville. Between diagnosing multiple problems and waiting for parts to come in, it was a longer-than-usual wait for me. Losing the use of my precious machine in the middle of August began to hurt my psyche. And then I got the bill, which really hurt my bank account!
Photo at upper right: The mounting bracket for my air filter was cracked all the way through on one end.
My friend Mike Russo stopped into Jimmy's shop last week and when he recognized my bike sitting there, he asked, "What's wrong with it?" The mechanic who happened to be working on it at the time retorted, "He rides it too much." That's the lesson I have to keep reminding myself of: the more I ride, the higher the maintenance cost. Per mile, it's actually less expensive for maintenance when you ride regularly and for significant distances. This thus gives me the perfect rationalization for riding more. :-)
Jimmy & co. worked on four problem areas, in order of difficulty, easiest to most laborious:
- Replaced the compensator
- Junked the old air kit, intake seals, etc. and installed a whole new, differently-designed air filter system
- Cleaned the valves
- Replaced the lifters (aka "tappets") and inspected the cams, oil pump, etc.
Compensator
The compensator is a part that is actually designed to take a beating. The issue is how long will it hold up? The short answer as to what the compensator actually does is the "compensating sprocket buffers torque from the engine." Put another way, the compensator unit, which is mounted on the end of the crankshaft, serves as a "torsional or vibrational damper...to reduce the torsional vibrations often caused along the length of the crankshaft." The compensator on the Harley (part no. 40384-91) uses a special kind of spring to absorb undesirable vibration on the crankshaft.
Photos at upper left: Front and back views of the old, worn compensator from my 2006 Electra Glide Classic (FLHTCI). It's hard to believe this simple-looking part costs $160 from HD.
Fortunately, the compensator is relatively easy to get to and replace on the Twin Cam engines. The hard part is paying for it. The Harley-Davidson OEM part costs about $160. There are aftermarket versions selling for $75, e.g., J&P Cycles. Jimmy used the OEM part and I don't blame him. However, I would love to know how the aftermarket versions measure up against the HD part. With such a huge difference in price, I might be tempted to try the cheaper version next time.
Broken Air Filter Mounting Bracket
The reason I took my bike to Jimmy was because the engine was losing power intermittently and the problem was suddenly getting much worse. I suspected a problem with the fuel-air mixture. I first noticed this misfiring when I was riding with Cutter to Key West a couple of months ago. I cleaned the air filter when I got back but did not notice the broken mounting bracket. (See photo at the start of this blog post.) It turns out that my air intake seals were also dried out and brittle. Jimmy suspects the ethanol gasoline we have to use caused the premature deterioration of the seals. He thus recommended I use a fuel additive and he sold me a bottle of StarTron Enzyme Fuel Treatment to mitigate the effects of the ethanol. (See photo below for a picture of the bottle I bought.) The reviews for this product on Amazon are generally very good. I plan to do some more research on the ethanol issue and report my findings in a later blog post.
With my old air intake system, I frequently had unburned fuel blow back out through the cylinder head vents where it then dripped on the engine and blew back against the saddle bag. My expectation is that I should see no more of that with this new air intake system and cleaner valves.
When I asked Jimmy if he thought the problems with the air intake system were the source of my engine problem, he was skeptical. In the end, he did not offer a theory as to the source of the problem. However, I suspect the carbon-coated valves were the culprit. (See next section.)
Excessive Carbon on the Valves
Jimmy found that my valves (two intake and two exhaust) were coated heavily with carbon. Given his surprise as to how much carbon buildup there was, it would not surprise me if that was the primary cause of the power loss. The ethanol may be a contributing factor to the carbon buildup and my hope is that the fuel additive will reduce carbon buildup and extend the life of the seals.
Lifters
The last time I had the bike in for maintenance, Jimmy commented on the noise my engine was making. He figured it was coming from the compensator (left side of the bike) or the lifters (right side of the bike), or maybe even both. He replaced both. My hearing is poor, so I am not one to detect higher-frequency sounds coming from my engine. My wife also said she heard some rattling too, so I'll assume I missed it. In any case, the engine runs smoothly and quietly now. Fortunately, Jimmy installed adjustable push rods in my bike when he did the performance work for Mitch back in 2006 or 2007. Adjustable push rods make getting the lifters out much easier.
The bike's power performance improved so much that I had to be extra careful Friday evening and yesterday as I acclimated to my engine's revitalized muscles. The bill may have been a big one, but I sure did enjoy having my bike back yesterday as I rode down to Reno Sharpe's Music Store on Pittsboro-Goldston Road near Goldston, NC.