Dyna Update!

Fork seals

Ugh. Hydraulic forks are the best... until they're not. Most people will ride their motorcycles for years without ever even servicing them. The maintenance is pretty straightforward, most of the routine services simply require draining the old fluid and replacing it with fresh stuff, which, in a lot of cases, can be done without even taking the forks off the bike. Most fork seals last for years, and for thousands of miles, as long as the fork tubes are kept clean and free of debris.

But if you're a project hunter, like me, who can't turn down a great deal on a bike that needs a little love, chances are, you're gonna be doing a helluva lot more than simply swapping fluid. I've got two such bikes sitting in my garage, right now. One, is an '06 Sportster that I picked up for less than $2k a few years ago, and the other is an '11 Dyna Street Bob that I added to the stable a couple years later. Both of them were complete, but in deplorable condition- rust and corrosion was rampant on both, neither was running and both of them had been neglected for several years. But... I got them cheap and trusted myself with being able to get them back on the road, which I did. 

Both bikes have been awesome, but both have had the common issue of fork seal leakage, in part because I half-assed the job the first time on both bikes. Let me explain.

Sporty

When I first got the Sportster, the fork tubes were obviously roached. They were pitted with rust from top to bottom. The sliders were fine, but the tubes were simply beyond repair. Where I half-assed it, was I stupidly went on eBay in an attempt to save a few bucks and bought a set of used tubes that were significantly better than mine. With a new set of Genuine James Gasket seals and my new used tubes, I put her back together with some fresh 10w oil and she was good to go, for a few years anyway. After a few years of riding, one of the seals sprung a, very minor, leak. It was just minor enough to make me doubt if it was actually leaking, but after a few months, I realized that I was going to be doing a fork seal job again. 

Dyna

When I first picked up the Dyna- a 2011 FXDB Street Bob- I already had some knowledge of the bike's history. I bought it from a friend who, several years earlier, had bought it from a local Harley-Davidson dealership. He was the second owner of the bike and I was actually with him when he bought it. As it turned out, he didn't ride the bike as much as he thought he would and it ended up sitting in his driveway under a bike cover... for years. I hadn't seen the bike since he bought it and had no idea how bad of condition it was in before I agreed to buy it. It really didn't matter to me though, because for the price he was asking, it was worth it. When I first saw the bike, I was in awe of how bad it was. For a bike that was only 7 years old with less than 10k miles, it looked as if it had been abandoned in a field for a decade. I guess that's a drawback of living in the south, near the Gulf of Mexico- the salty, humid air makes short work of corroding metal. The ethanol based gasoline did it's own damage to the inside of the fuel tank, but that's a story for another day. 

The fork tubes didn't look too bad at first glance- the uppers were a little spotty, but the lower sides looked fine, even though they were both leaking. I assumed that the seals were leaking due to being dry rotted, and I wasn't completely wrong, so in my eagerness to ride the bike, I bought a set of Genuine James fork seals for it, then tore it down and put it all back together in an afternoon. I was stoked to ride it... for a few hours anyway. I assumed that the problem was with the seals, since I had previously installed a set of the same brand on the Sporty and they were now leaking after only a couple of years of riding. In my frustration, I cussed the Genuine James Gasket Company for all they were worth, then went online to do some research.

The Sporty fork saga, continued

Having had my fill of frustrations with the James Gasket seals, all my research pointed me to ordering a set of All Balls Racing seals for my trusty little XL. Once I got it tore down, however, I quickly realized that the seals weren't the problem. Apparently, something (probably sand, since I live near, and often ride beside, a beach) had gotten under the dust seal and made a nice little scratch on one of the tubes. The eBay tubes, if I'm guessing by their appearance, were most likely show chrome which is pretty, but not the most durable for a machine that is ridden a lot, so I bit the bullet and ordered a set of new hard chrome tubes, made by Hard Drive. I put it all back together with some 15w, for a little better dampening. She rides better than a new bike now...with no leaks!

The daggum Dyna

I like this damn bike, a lot, but boy it sure makes me cuss sometimes. After getting the new seals, I tore the forks down and, after a quick inspection of the tubes, put it all back together with the new All Balls Racing seals. Success! No more leaking! I was ecstatic... such a simple fix... 

...or so I thought.

Within about a month of riding, that familiar old bead of oil showed up on the high side tube again. I put the bike back on the lift, pulled it apart for what felt like the hundredth time, and inspected it like a jeweler inspecting a diamond. All of a sudden, I saw it- a small, barely noticeable, chip in the chrome, just above where the seal sets when the bike is at rest. The chip was small, only about a millimeter in diameter and was barely discolored, making it hard to spot with a quick visual inspection. The location was such that, when the bike was rolling on relatively smooth roads, the seal didn't cross over the chip, but when the fork compressed under a harder bump, the seal crossed the chip and a tiny bit of oil would leak past. 

As I dragged my fingernail across the chip, I felt it catch the edge and at that moment, I knew that I had, now twice, cussed the Genuine James Gasket Company in error. Oops... sorry guys.

I did my best to try to smooth and polish out the chip, to no avail- it continued leaking, so I called my local indie shop, French & Son's, and ordered a new set of Hard Drive hard chrome tubes and a new set of All Balls fork seals. Once I had them back in the shop, I put the Street Bob back on the lift, tore it down for what felt like the millionth time, and went to work. Having pulled the forks apart so many times, it didn't take me long to install the new tubes and seals. I topped it all off with some fresh 15w fork oil, put it all back together and rolled it off the lift... again. This time it's (finally) fixed and now it rides better than a new bike, too. 

The lesson learned

My dad used to tell me that if you're going to do something, do it right the first time. Well, for the Sportster, the biggest mistake I made was trying to save a few bucks by buying a set of cheap, used fork tubes. In my defense, they lasted a few years before they got scratched. That could have happened to anyone, I suppose, but by buying the tubes used from an individual, I had no specs on them and ended up buying a set of nice looking, but not very durable, show chrome fork tubes that were susceptible to getting scratched. With the Dyna, however, I'll admit that I half-assed it from the jump. I should have taken the time to inspect the fork tubes before I ever put it back together the very first time, but I was trying to save time and money so that could get back to riding the bike as quickly as possible. In doing so, I ended up having to do the job, way more times than I should have. Besides the aggravation, I also wasted valuable time and money on seals and oil. 

Now that both of the bikes are back together, I can focus on actually riding them. Maybe, while I'm out riding, I'll stumble across another project bike that I can tinker with. One thing's for sure though, if I do get my hands on another crusty project, I won't be cutting any corners when dealing with hydraulic fork tubes... I might just go with a springer front end, instead!

Regardless of what you might find yourself working on next, remember this:

If you do it right the first time, you'll only have to do it one time.