Wednesday, August 01, 2007

Splined Faith...

[Warning! What follows is long-winded, largely imageless, and stippled with indecorous references to certain body parts, scatological products, intimate acts of a venereal—if metaphorical—nature, ribald euphemisms, and mechanics-of-solids principles.]

“Hold up, man, I think my cleat has come loose...”

Twenty-two miles into the Outlaw’s 1903 Adventure Ride, I gently resist the persistent push-pull of the cranks and slowly steer my fixie to the side of Crow Rock Road. I've got a problem. There's a strange wobbling sensation coming from beneath my right foot. With about 30 miles left on the ride, it doesn’t bode well. Butch slows to a stop. No cars pass us on this lonely swath of pavement in rural Frederick County, Maryland, as I begin to investigate Fate's dubious gift.

We've just finished a short, fast descent after suffering a steep climb up Moutaindale Road, an interminable stretch of gravel-laced hardpack that never pauses to let a breath float unforced into the lungs. It's arguably the most hateful segment of this timely tribute to the early Tour de France days, when pre-EPO-era cyclists pedaled pre-carbon-fiber fixed-gear frames to victory or defeat over teeth-chattering cobblestones, with the humble lure of a fine bottle of Bordeaux and a smoldering Gauloises Blonde looming just beyond the finish line. Armed with an elaborate cue sheet, Butch and I are going it alone because we showed up more than an hour after the scheduled start time. Donna has joined a ladies ride at the 'shed. The others on this ride, the group proper, are somewhere up ahead of us. Once again, we've become the SSOFT Leftovers.

(Grab a coffee...or a beer...it's a long, rambling story that, if you can imagine, ends in a brewpub. Of all places.)

Flashback several hours to early Saturday morning. I show up at Butch's place with a chainless bike (I'll explain later). I'm late already, Donna is late in joining us, and Butch has been waiting. I quickly try to throw on a new KMC Kool chain while Butch stows his gear. It's a heavy-metal mutha, this silver and black coil of fat links, an industrial asp that screams ponderous and unbreakable in the same breath. The Surly 1x1 of the chain world. What the eco-wretched Hummer can only dream of being when it forgets for a minute in mid-doze that it's merely a glorified Suburban. Get the picture? Problem is, the quick-link is knackered (manufacturer's defect?) and I can't couple it. After rummaging around in my toolbox, I locate a new SRAM PC-1 chain, measure it out, break it in the right spot (along with the chain tool itself—thanks, Park Tools!), and throw it on using the quick-link.

Now, the PC-1 chain is cheap for a reason best summed up in terms unanimously approved by the much-vaunted American Society of Mechanical Engineers (ASME): it's a veritable "piece of shit." Butch warns me it's a veritable piece of shit. I know it's a veritable piece of shit. But, I reason, mind thinking in italics, even a veritable piece of shit has gotta be good for one ride, right? I mean, c'mon, right? Mistake 3 (nomenclature dictated by the chronology of events) rears its monstrous head unnoticed in some dark corner just off stage.

On to the present saga. All morning long, every mile of the way, Butch has thrown it down like a blood-dope-fiend, handing me my ass in a candy box nicely wrapped in a pink-pansy motif. I can't help but think he's amped up by the opportunity for payback over last year's Dirt Track Date ride. The hill we've just finished is the same hill we battled for then, when I topped out in the lead. The evidence of a tacit vendetta is compelling, even in the post-climb stupor that settles in on me now. Butch is a competitive guy (something about overcompensation and all that, ha). Still, I convince myself that lack of sleep and a foolishly-steep gear are the real culprits. But the melancholy truth* is that Butch is clearly stronger than me today. Period. It's not supernatural.

With a slow, delicate twist, I coax my foot out of the jaws of the clipless pedal and I’m greeted immediately by the root of the problem: in place of the normal 90-degree bend at the junction of crank arm and pedal spindle is a new angle: let's go for a visual here and call it "post-coital" (a particularly apt term, since it's clear to me now that I'm, well, to be indelicate, pretty fucked). I extend the metaphor by uttering a popular, though nonetheless satisfying, expletive.

"How bad is it?" Butch asks.

"Pretty fucking bad." (The metaphor grows, distends, blossoms.)

We stare at the senseless carnage. The pedal dangles from the end of the crank in a posture of effete surrender. In seconds, 1900s Tour de France lite becomes Tour de Farce. Heavy.

Flashback to the previous evening, Friday. The Cross-check hangs motionless on the bike stand as if impaled. Beneath it on the tiled floor, like a tasty oblation, a half-full beer bottle stands in a thin pool of condensation, as if it's pissed itself. I'm installing a new pair of Deore cranks in place of a not-so-old LX pair. The original non-drive crank has developed play in it, an inevitability first predicted by Jobst Brandt, who surmised a priori that Shimano's splined Octalink system (a solution to a problem no one had), lacking a taper shape and thus precluding a traditional press-fit, would spell trouble for fixed-gear use.** With only the bolt to hold the crank in place, Brandt posited, the pressure from backpedaling (or, for gearies, from coasting repeatedly with leveled cranks over rough terrain) would create a fretting motion at the crank-spindle interface. Because the steel of the spindle is the more durable of the two materials, the fretting would gradually wear away the splines on the crank arm. Soon, a brief but nonetheless annoying pause or dead spot in the pedal stroke would introduce play, and things would get worse from there. With the slight "backlash" movement of the cranks would eventually come the loosening of the crank bolt. And increased fretting. But no amount of torque on the bolt can reverse or prevent the ongoing slop, since unlike with square taper BBs, the bolt doesn't force the crank onto the spindle via a press-fit. Yep. Seems to match my experience. Of course, I don't read about this until later. So I replace a splined Shimano crankset with a splined Shimano crankset. At the same time, I replace the bottom bracket; with about 14,000 miles on it, it's probably a good idea. I think I've got the spindle length correct, but my chainline seems a bit off. Which brings us to Mistake 1. After fighting to remove the old pedals, I transfer them to the new cranks, easing up on the torque a bit so they won't be too difficult to remove later. This cautionary—and hugely uncharacteristic—act introduces Mistake 2. I leave the installation of the new chain for the morning, figuring from past experience that it's a five-minute job at worst. My sleep is fitful and largely unrestorative.

Returning again to the present saga. Somewhere along the route this back-stabbing pedal backed itself out of the crank arm until only about a third of the spindle threads are engaged with their now-mutilated counterparts in the crank arm. Incongruously, the effects of Mistake 2 play out before that of Mistake 1 (mysterious Fate showing little reverence for a rational order of events), the details of which unfold shortly.

The next fifteen minutes are lost in a desperate and tedious attempt to re-insert the pedal spindle in the crank arm. At first I flounder at the task like a nervous sophomore on his first lucky date. The pedal begins to thread on properly, only to kick out to one side with the next twist. Again and again, the same crooked result. We don't talk about it, Butch and I. Each of us is well aware that a walk-out at this point isn't really an option. Meanwhile, we slip futher and further behind the vanguard, who are likely enjoying a cold one in some tavern along the route just about now.

Finally, with a little otherworldy patience, I get the spindle to take. I tighten it gently, carefully, mindful of the fact that at best one-third of the threads are biting one another, and at the same time knowing that a too-loose attachment risks completely wallowing out the pedal eye some time later during the ride.

And then we're spinning again, rolling through a slight downhill with me in the lead. As I bitch aloud about the new crank and its now compromised and untrustworthy condition, Butch plays the optimist, "At least that piece of shit chain is still holding together." With this simple statement, he unwittingly ushers in the evil of Mistake 3. Fifteen seconds later, the piece of shit chain splits cleanly at the quick-link, uncoupling near the chainring like a cheap necklace and flying back to drag between cog and hub flange. I come to a gradual stop with the help of the front brake. I curse as I try to recouple the chain using a segment I had the good judgment to pack with me. I get it on and, with the hub axle all the way at the back of the dropouts, it's a bit slack. Still, better to have more chain than less, in case I meet with another break. I jokingly shout skyward, "Is this the best you've got! What else, what's left? How about a lightning bolt? Where the hell is that?" Alas, no electrical discharge rockets from the heavens. Butch shakes his head, and begins lecturing me about chainline, telling me how bad mine is right now.

Five minutes later, we're on the road again, pedaling along a flat section for a short while. Then it's another downhill. With the weight of my feet on the pedals, the misaligned chain wants to leap off the ring, and leap it does, landing up front on the pedal between my foot and the crank arm and in the rear on the hub axle. I coast to a stop with the untethered cranks leveled at 3:00 and 9:00. Butch continues on a bit, at first unaware of the new development, the fruit of Mistake 2. He circles back and, as I put the chain on again, tells me how bad my chainline is. I mount up and we roll on.

It isn't long before the chain skips again. Butch holds up for me, commenting on how bad my chainline is. I decide that the idea of wrecking at 30 mph and ending up chaff under the tires of a some nondescript pick-up truck when the chain finally decides to jam in the cog isn't at all appealing. I shorten the chain, taking it down a precious link in hopes of getting it taut enough in the dropouts to keep it securely circling ring and cog for the rest of the ride.

On the very next downhill, the chain pops off again. Butch takes a minute to tell me how bad my chainline is. We quickly come to an agreement that there's really not much I can do at this point about the goddamn chainline. I decide henceforth to let my feet dangle on all the downhills so that the cranks can spin unopposed by any counterforces. It's a successful—if unnerving—strategy. With only a front brake now available, the situation is a bit sketchy on several long, narrow downhills, where I occasionally pass Butch as he resists the spin of the cranks for control. We continue on like this for another 25 miles, Butch in the lead, me trailing behind, alternately pedaling on the flats and climbs and "coasting" on the downhills.

Eventually and without further incident, we make it to the shop (the point of origin), load up the bikes on Moby Dick, and head over to join the others at Brewer's Alley. I make it a point to water down the day's disturbances with my share of Resinators, the oh-so-hoppy double IPA that BA has on tap. Soon, amid good conversation and a flurry of rounds, the agony of fifty-four mechanical-ridden miles dissipates like the head on a fresh pour. I feel all right. Amid the conversation, Butch takes a drunken moment to point out how bad my chainline is.

[Epilogue: I've since realized the many errors of my few ways and picked up a nice set of Sugino XD500 cranks in a no-pedalstrike 170 mm length and with a monster 50T chainring. Oh, and they're square taper. Butch, you'll be happy to know that my chainline is spot-on. Nice ridin' with you. And thanks for your patience.]

*With apologies to Clare Quilty...the character, not the eponymous band. Lo and behold, a literary reference!

**For more information on crank-spindle fretting, see this informative Wikipedia article on precession. This Web page may also be of interest.

Oh, and tip back a pint in honor of Pierre Bourdieu, who, in a truly just world, would have turned seventy-seven today.


Belated props go out to Joe for creative route-plotting and flawless cue-sheet design. Nice work!

6 comments:

buchetti said...

Even with all the set-backs on the ride, this was one of the best rides I've done. I really didn't think we'd finish the ride. To say it was unnerving to descend a steep, gravel road and look back to see Steve unclipped on a fixed gear with only a front brake as pickup trucks and BMW's zipped by is a drastic understatement. And yeah, your chainline was WAY off!!

riderx said...

It took long enough for the report, but it was worth it.

Ricky and Erin were play the same "feet off of the pedals" game on some crazy downhills. Unnerving is right, I'll take my chances with my feet on the pedals, thank you very much.

Version 2 of the 1903 ride has already been mapped. Looks to be around 60 miles and probably more climbing.

Ooh Shiny said...

Highly entertaining report. I have passed the address to all of the cyclists in my office. Thanks for sharing.

Dave

Hjalti said...

Awesome story. It builds your character see...

DT said...

Big fan of the Sugino cranks. The best thing you can say about them is they just work. Glad everything worked out on the ride in the end. Bet that was a great post ride beer!

Olly said...

NOT ONLY is splined rubbish in all cases,
but the extra size on the spindle = small bearings which will get mashed up good and proper in half the time.
splined is for those Iron Lemming DH riders who cant take the rough with the smooth.
Outboard bearings are the way forward, but until they are less of a shitmmano monopoly, stick with the SqTp