Showing posts with label earwax. Show all posts
Showing posts with label earwax. Show all posts

Tuesday, September 05, 2017

Fixing the unfixable

As I was picking congealed grease out of a Shimano Rapidfire shifter pod dating from about 1991,
I actually appreciated how solidly it was made, and how reliably it worked compared to its temperamental descendants. Early versions of a product, even one with lots of conceptual flaws, will be made much better than later versions, because the promoter doesn't want it to self destruct before establishing itself among the uninformed as a solid product. Only then do the manufacturers start watering it down to increase profits.

I hated the underlying concept, and still do. Shimano announced Rapidfire in a triumphant video that they sent out to shops before the 1990 season. We watched our copy in horror, anticipating in full detail the hell that it would unleash on mechanics and riders. We could do nothing to stop it, despite my best subversive efforts. It included the admonition that there was nothing we could fix inside these pods, so don't even try. Word in the cycling press was that intrepid mechanics had disassembled brand new units and reassembled them exactly as they had been, and they mysteriously failed to function. Whether this was true or was disinformation planted by Shimano I never found out. It implied that there was some magic Shinto pixie dust inside these units that would fall out if barbarians profaned the interior.

I plastered these cartoons all over Interbike's Philadelphia show for a couple of years:





It was, of course, to no avail. The technofascists won, leading the technolemmings off of cliff after cliff. But I digress.

The 1991 pod clicks solidly into gear as soon as you flush out the pus that they used for grease. It congeals into a substance we call earwax. My colleague Ralph came up with that one. He was an excellent wrench who was smart enough to get out of the business. It's been bad for his waistline, but probably good for his bottom line, to pursue his interest in computers instead of the 19th Century technology of the bicycle, dolled up with 21st Century materials as it is today.

When hackers and their malware finally make the Internet untenable, bicycles will be waiting to receive the refugees of the Digital Age.

Back to the pod from '91: it felt weird to have so few clicks. I've had to clean out many later versions, chasing more gears, so an original six-speed feels very short. But the wider spacing with fewer stops provides more margin for error. Cable tension has to be relatively accurate, but not neurosurgically precise.

Within a couple of years, the Japanese Buggernaut had enclosed the pods more completely and nearly doubled the number of parts inside. This made them less vulnerable to invading grit and mud, and generally more reliable. It also concealed the insidious activities of earwax under a Darth Vader-like black mask.

In the 1990s, the bike industry, led by Shimano, used the customers mercilessly as test pilots. You might expect such shenanigans from small companies making boutique componentry, but you saw more of it from the big players with lots of leverage. You see it today as manufacturers hump their customers in vulnerable "enthusiast" categories with model year changes intended to make addicts want another hit. There are no white hats in the big componentry business. With the coming of the Electrical Age, batteries are all the rage in everything one might electrify.

Honestly, how did any of us survive the 1970s and '80s on the paleolithic crap we had to ride? In his book, Four Against the Arctic, author David Roberts told the story of four Russian hunters in the 18th Century who survived on an island near Svalbard for six years before being rescued. He and other members of his research team observed that people from a later time, less inured to routine hardship, probably would not have survived. Indeed, look how many perished on Arctic exploration trips when their technological cocoon ripped, dumping them into the elements where Inuit survived and thrived.

We're not Arctic explorers, but we are certainly allowing ourselves to be increasingly isolated and softened by accepting more and more technological intermediaries between us and the realities of the tasks we choose to tackle. Some of these can enhance safety and functionality, but an awful lot, particularly in cycling, pander to riders in search of marginal gains at more than marginal increases in cost, and drive perfectly functional older stuff underground.

Would I miss my outlaw bravado if the stuff I use was totally mainstream? Against what would I rebel in Biketopia, with beautiful routes and intermodal interfaces everywhere? Why don't we build it and find out?

Tuesday, July 15, 2014

A friend's used bike

Between 1994 and 1996 Shimano seemed determined to set a definitive low point so that whenever anything went wrong with componentry they made after that they could say,"yeah, well at least it's not as bad as THIS crap."




These M290 Acera shifters from about 1995 are some of the worst they ever made. At best they feel like they're about to break. They feel flimsy in a way that implies that when something does snap in there it's going to jam up the whole works.

Usually what snaps is the cheesy gear indicator. Several models of Shimano shifter had cheesy indicators that year, all prone to failure.

The shifter mounting tabs on the levers push the shifter pods into the rise handlebar, restricting them to a fairly steep angle. The plastic is so cheap that the nozzle broke off the right shifter, so I had to fabricate a metal ferrule into which to insert the cable housing. I cut a Schrader valve cap and pressed it onto the old adjuster I ground down to use as the ferrule. When I tried to use the adjuster full length, to provide convenient cable adjustment at the shifter and not just the derailleur, the threaded shaft of it jammed the shifter mechanism. Ground down, it made a more substantial ferrule than any of the others I had in my parts farm.

Purveyors of technology would ask, "why are you still running this crap? Buy our new stuff." It's not built to last. It's built to be replaced regularly. Hell, some of it isn't even built to be USED.

The M290 crank that went with this gruppo originally is one of the trio of "Cranks of Death" from the great recall of 1997. The others are the CT 90 Altus and the MC 12 Alivio. A few are still roaming around out there after all these years. We have treated two or three this summer. Cranks of Death is just a pet name. No actual deaths have been attributed to these cranks, only injuries including fractures.

A couple of years ago I had already replaced the original Crank of Death on this bike with a nice replaceable-chainring model and done a comprehensive tune up. Aside from the position change I had to de-earwax the shifters and pump up the tires. Those are on the verge of dry rot. I'll tell the owner to ride a lot to get full use out of the tread before the tire casing disintegrates. Maybe do some skids.

Saturday, April 05, 2014

Dual Drive earwax

One of the early repairs this year is a Cannondale hybrid with SRAM Dual Drive rear hub. The owner said the bike had been stored for a couple of years. He reported no functional problems, only requested that we figure out how to raise the handlebars.

Dual Drive uses internal hub gears combined with a freehub body to provide a set of external gears shifted with a derailleur. This particular bike had a three speed hub.
A single unit controls both internal and external gears
The control linkage for the internal gears has been disconnected in this picture. 

While I had the wheel out for truing I noticed that only one of the internal gears was engaging. I remounted the wheel to confirm this by reconnecting the shifter. Yep. It was totally air pedaling in low and medium gear ranges. This was not just an adjustment problem. 

With a little Internet mining I got to a tech manual on SRAM's site that showed me how to break into the thing, but I saw nothing in the schematics that suggested an obvious flaw that would lead to this kind of gear loss. The troubleshooting guide made no reference to it. Based on some residue on the end of the hollow axle I suspected congealed grease in the "lifetime lubricated" inner recesses. I flooded the hub with light oil and left it overnight. 

This morning it works.

Thursday, May 03, 2012

The Italians don't get earwax

Shimano's very clever indexed-only shifters notoriously suffer from congealed lubricant that makes them quit working. When Rapidfire shifters were shoved down our throats introduced in 1990, Shimano made sure to let everyone know these shifters could not be serviced. We were told to replace any units that ceased to function. Dutifully, we did so. Enterprising mechanics tried to teach themselves how to work on things in there, but usually the patient died. The mechanism was intimidatingly complex and the basic problem was little understood.

These days, whenever an older bike comes in we routinely check for earwax and perform preventive or corrective procedures. We hardly ever replace a shifter anymore.

The road shifters are somewhat less prone to earwax and much harder to service if they develop it.

Campagnolo's Ergopower road brifters do not develop earwax. That's the good news. If something goes wrong you can repair the shifters using Campy's detailed diagrams and fully-listed spare parts. The bad news is that you have no excuse not to.

The fun starts here

Follow these simple instructions

It doesn't always have to be like this
This is on my mind because I just did ratchet springs in a Campy lever last week and now I'm doing about the tenth de-earwaxing of the young season on a 1993 or '94 mountain bike with Shimano trigger shifters.

No one has brought me any of Campy's flat-bar shifters, so I don't know what they're like inside. If you only learn things as you need to you have plenty of brain space left over to use as a playroom.