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Saturday, July 3, 2010

Oh Boy...

As if things weren't busy enough, the fork on my bike decided to "shit the bed" during the final lap of the race at Northstar the other night leaving me with absolutely NO rebound or compression. As my fork "clunked" its way towards the finish line, I couldn't help but wonder what was going on in there and why it happened now.... one week from Downieville.... with little to no "free time" before heading down to the race.

Embarking on an intricate job (which this would be) that you've never done before is kinda
like a box of chocolates. For this job, I kinda understand what's going on in there. The new F.I.T cartridges in Fox forx remind me of Showa forks that used to come on Honda CR125's and 250's. When I was doing Race Tech stuff with motos years ago I'd re-built a handfull of these. Their a "bladder style" damper cartridge that houses all the oil, valves, valve shims, port holes, needle valves and countless super tiny o-rings.

I was a bit anxious to figure out what happened in there. Was it a failed o-ring that I'd have on hand, or some "unobtanium wonder part" that Fox would be out of stock on? The first of these options would have me back together in time for the 6 pak super D later that same night, but the latter would force me to "step up" and race the one speed for Downieville.

I gave the fox site a look to familiarize myself with the "lay of the land", grabbed some tools and dove in. I had theories ranging from something as simple as a bad seal to my "outside the box theory" with a more scientific approach like reduced vapor pressure and low humidity coupled with magnetic variance and gravitational attraction. A half hour later, I'd realize that the top cap had come loose from the bladder shaft. I figured that since I rode the last lap at Northstar with no oil in my fork, I'd better have a look deeper inside. An hour later, my fork looked like this.I figured out that it doesn't take a whole lot of time on the trail to ruin the bladder seal when the fork is out of oil. Then, I ran out of time. My 10:00 appointment for a wheel that needed a spoke and a bike that needed a tune was rapidly approaching. I hopped in the van and headed out for a day of work.

During my day I found a replacement bladder from The Backcountry (LBS) while having lunch at one of my favorite spots in Truckee. Once back at Mighty Mobile headquarters, I continued re-building the damper assembly. Slowly but surely, things went back together. It took eight times longer that it will the next time (a common situation with a first time repair such as this). Bleeding the cartridge is a multi-step and time consuming process. Even the directions from Fox say "take a break.... up to 30 minutes.... air bubbles... blah blah blah".... ok, maybe I'm making up the blah blah blah part, but it's still time consuming.

So, the next step will be to get the cartridge back in the fork and put a few miles on it before heading to Downieville for a weekend of pain and suffering. Coincidentally, I was just on the Downieville Classic site and have learned that they have 15 spots open for the All Mountain Pro Class. These spots won't last long seeing as the race sold out in 15 seconds when they first opened registration.

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