Month: October 2011

SKF Seals and another fork rebuild

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The new SKF fork seals came in a couple of days ago, been trying to clear some time to get them installed and get the bike back together. These seals are supposed to be the hot setup for 48mm WP forks, as the stiction from stock KTM seals, as well as many aftermarket seals like the pure crap All Balls.Moose.MSR seals on there now, is well known.

Upon disassembly of the forks, I checked the upper and lower bushings. Both looked good, and really as though they may have recently been replaced by the previous owner. Cool. I also took the opportunity to do a little more work to the compression and mid-valve shim stacks (my mods are based on the ’07 Trail Tricks stack as found in the ktmtalk.com forums). Gave everything a final cleaning and inspection and started reassembly.

One tool I sprung for was an actual purpose-built seal driver (instead of half-assing it with an improvised tool made out of PVC). I bought the Cycle Gear house brand ‘universal’ seal driver that’s supposed to be good for forks from 30-something to 50mm. While it did work, I found it to be awkward, as the two halves did not mate up properly on the 48mm fork. Also, the part that actually contacts the seal doesn’t look like it’ll hold up for the long haul. If you can afford it, I would skip the ‘universal’ route and spend your money on the correct sized Motion Pro driver.

Anyway, reassembled with the new seals and dust wiper, and just like in the video, the improvement was dramatic. I filled each leg to 140mm with Mobil1 synthetic ATF, put the front wheel back on, lowered the bike back on the ground and gave the forks a push. Man, they were like a new, different, better set of forks. Where before they were jerky and stiff, they were now buttery smooth and supple. If they perform on the trail like they seem to promise here in my garage, we’re back in business. I hope so, getting tired of pulling these forks apart (have I said that already??).

Race Report: VCHSS Cross Trails 10-16-2011

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Bob at VCHSS Cross Trails race 10-16-2011

It was a beautiful day in Cartersville, VA. I headed out before dawn since it’s a 3-1/2 hour trip. Arrived with plenty of time to spare (for a change).

The layout of this course was interesting. There’s an infield area where the course is marked off with tape. When you enter it coming from the woods, you hit a flat straightaway for maybe a hundred yards or so, then a very muddy 180 hairpin, back up about 75 yards, through the scoring tent, then out through a large piece of storm drain pipe, down a bit and then over some truck tires endurocross-style, back around and then over the pipe, around a large, fast sweeper, through a couple more mud puddles and finally up a big hill and into the woods. (couple of vids here and here)

In other words, plenty of opportunity to be either a complete hero or total dork in front of a pretty large crowd of spectators.

The start was dead engine, front tire over a log with 30-second intervals between classes, so it went quick.

My plan was to hang back and tail the back end of my class for the first lap and then start actually racing come lap 2. I hadn’t competed in 11 months and needed to get my racing legs back under me before mixing it up with other riders.

Starting flag went up and we were gone. I got a great start, somewhere in the top 5 or 6. This 300 is a beast off the line; there was plenty of throttle left if I needed it. BUT, I backed it off because up front was not where I needed or wanted to be at this point of the race. I let several of the faster guys by, but realized that waiting for the rest of the pack – who were in no apparent hurry to get past me – wouldn’t do. I picked the pace back up and got into the woods somewhere mid-pack.

Once in the woods, it got nasty, quick. Almost immediately we were in some super tight, rutted, rooty, rocky and worn-out single track that had obviously seen more than its share of races. The massive bottleneck that followed took probably a couple of miles to clear, but I was able to make a few passes for position as riders in front of me went down or tried shortcuts that didn’t quite pan out.

Once the bottleneck cleared, I was in with a pack of about 8 or 9 riders and settling into a decent pace. However, this is when I began to realize a couple of things – a) my front suspension was still awful, and b) this may have been the wrong race at which to to try and stage a ‘comeback’.

Ooops…..

Anyway, catching and passing this group in front of me wasn’t too difficult, staying in front of them was. The front end of my bike was skating all over the place; no sooner would I get the last of this pack behind me than the front wheel would either deflect off a root or pop out of a rut in the middle of a turn and down I’d go…and right back by me they went. This pattern would repeat itself several times over the first lap and a half.

Lap 2 was more of the same. I was getting beat up pretty bad, triceps and shoulders felt like rubber and I had fallen way off the lead pace. Finally, near the end of the 2nd lap and tired of hitting the ground and fighting – rather than riding – the KTM, I’d had enough. Pulled off to the side of the course, took a few minutes to adjust the forks (slowed the rebound a bit to help it stick better in the corners), take a B-I-G pull from the Camelbak, and then got back to it.

The third lap was better. Decent actually; I’d gotten my second wind, and along with it, a better feel for how to get around this course. My speed was better, I was smoother, but the forks were still killing me. I was getting tired.

About 3/4 of the way through this decent-but-relatively-uneventful lap I came upon a rider who was off their bike at the side of the course and yelling like crazy for some help. Typically, when a down rider calls out for help from another passing rider, it’s because of something major – broken bone, medical emergency, etc… so of course, I stopped. What was this persons emergency? Their bike was stuck on a root and they couldn’t get it off by themself. Yes, I was a little irritated, but I’m nothing if not chivalrous…..

Anyway, back on the bike, I finished off the lap and took the checkers 17th in class (out of 22).

I was a little disappointed in both my finish and overall performance in this race, but as my wife reminded me, I was off the bike completely for nearly 9 months and hadn’t raced in 11, so all in all I really didn’t have much to complain about. She’s right, of course, but the competitor in me just can’t swallow a 17th place finish. Ah well, I’ll have another shot at it in two weeks when we race Birch Creek on October 30th.

The best part of the day? The big, greasy, gooey cheeseburger I allowed myself after the race. Screw the diet….for today, anyway. šŸ™‚

There was a bit of good news to be found though once the lap times were posted. On my last lap I was shown as 9th fastest in class. But, remembering that I stopped and helped that stuck rider, which easily took a minute if not more, and which when factored in means I was running a solid top-5 time for the last lap. Yes sir, I’ll take that.

The forks were in pieces on my workbench within an hour after arriving home and unloading the truck. The problem still continues to be massive stiction from these crap seals (they’re red, triple-lip style, which makes them either All Balls or MSR) someone else installed, so I sprung for a set of the new SKF seals that everyone’s raving about and should have them by the weekend. If these don’t do it, I’m gonna bite the bullet (and break out the checkbook) and send the whole suspension out to Trail Tricks in Ca for a full rebuild and revalve.

-Bob

10/16/11: Heading out for race #1

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UPS brought my race-day parts the other evening – 2 tires, tubes, rim strips, fork bleeders and a spare goggle lens. Started mounting up the tires and discovered I’d ordered the wrong size rear tube. As luck would have it, a friend had the right size ‘in stock’ and was able to use the one I’d ordered for his 250, so we swapped and I was back in business (thanks Bruce).

Tires on, chain adjusted, air filter cleaned and oiled, and a full tank of fresh pre-mix…can’t help but think I’m forgetting something.

Didn’t sleep well last night, but I never do the night before a race. That’s OK, it won’t catch up to me until well after it’s over. In the mean time, the goal today is to finish on the lead lap, and if that’s not doable, then just finish.

I’m pretty excited. Let’s hope I don’t suck.

-Bob

10/9/11 @ NCMP – Putting it all together

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Pulled the forks apart again this past week trying to hunt down and kill the source of the deflection and think I may have finally gotten it. Softened up the valving considerably and then, in a last-ditch effort to eliminate the stiction that many people claim is the main culprit with KTM fork deflection, shot some Pledge -yes, furniture polish – up between the dust wiper and fork seal, and damn if that didn’t seem to fix it. And, the shine and lemony-fresh scentĀ are the envy of the neighborhood!

So, headed out to NCMP this morning to see where things stood in terms of the bike and the rider. Still haven’t been able to complete three laps straight due to various factors (not the least of which was riding like complete spaz a couple of weeks ago), so maybe today would be the day.

It was beautiful out. Temps somewhere in the 70s, sunny, light breeze…just a great day to be outside. There were a bunch of people at the track already including several woods riders. I always get nervous when I see unfamiliar woods riders, because you never know when someone’s going to go the wrong way down the trails and crash you head-on you around a blind turn. We have our share of occasional wrong-way riders, but fortunately no serious accidents yet. I’ll need to stay extra sharp out there.

I got geared up (including my new, super-trick custom-made carbon fiber knee brace, which is teh awesome), spent a few minutes warming up and then hit the trails.

Almost immediately I sensed something wrong. TheĀ  steering was twitchy and it felt as though the front tire was built by Fred Flinstone. I cut my loop short and headed back to the pits. Upon checking, it became apparent that the genius who put my forks back together (me) forgot to adjust the compression screw and had it turned all the way in, which is full stiff. Fixed that and headed back out.

This was more like it, small roots, stumps and doll-head rocks – the things that had me pinballing all over the place the last several weeks – now just disappeared under the front wheel with barely a twitch from the forks. Smooooth sailing…time to get on it.

Banged out 3 laps in a row, somewhere between 21-22 miles with only a sub-3 minute stop to fine-tune some suspension adjustments, at full-on race pace with zero problems and barely breaking a sweat. It’s hard to gauge your speed when there’s nobody riding with you, but if I’m any judge at all, I should easily be competitive in my class.

First race back is this Sunday 10/16/11 in Cartersville, Virginia at the VCHSS Cross Trails event. I’m about as ready as I’m ever going to be.Ā  Putting a fresh set of tires on, oiling/greasing everything that needs to be oiled/greased, and then we’re ready to rock!

-Bob

10/2/11 @ NCMP

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Haven’t ridden in a couple of weeks, but have been working out, concentrating on cardio and upper body strength and endurance. These are areas where races are won and lost, and i’m gonna need every advantage I can get.

Didn’t do anything to the bike between last time and this time, because I wanted to be sure the suspension problems were real rather than just the result of a tired rider having trouble controlling the bike.

The plan today (again) was to go three loops flat-out.

Boy was it muddy today. It had raind a lot between last time and today and the woods can take forever to dry out when the weather cools off like this.

Did a quick lap around the flat track just to warm up…halfway down the first straight, front wheel comes up …. in third gear. This bike is crazy powerful, still getting used to it. Throttle control…throttle control….throttle control………

Anyway, had a decent first lap. Had to stop once to back off the fork rebound adjustment a little. With the extra weight of the mud building up on the bike, the forks were packing a little and causing some problems through the choppy stuff. After that, not too bad, though the deflection problem was still there. Looped it and landed on my ass courtesy of a bit too much throttle while wheeling over a mud puddle at one point, but other than that, a decent lap.

Completed the first loop and headed back to the pits to work on the suspension a bit. Spotted a friend of mine and asked him to help me set the rear sag (ride height), a two-man job. The sag turned out to be off by a rather significant amount. Got it sorted out and then headed back out.

Noticed a pretty big improvement right off the bat. The bike was tracking a little better but the turning was definitely sharper, which would hopefully help the bikes tendency to wash out (push) in the mud.

Ran two loops – approximately 15 miles – non-stop, flat-out. Felt good. Getting some speed back, should at the very least not embarrass myself too badly at first race in two weeks.

-Bob