Wednesday, August 17, 2005

Wrenching Change

I was down in Iowa over the weekend for a high school reunion and to see my father. I did a bit of riding, which I will report on separately, and also some bike work at my friend Paul's in Cedar Rapids. That's the subject of this entry.

WARNING! BORING BIKE TECH STUFF COMING!! RUN FOR IT!!

Most of the work we did to Henry's bike, a 1984 Trek 620 touring bike. (You can see the original brochure for it here on the excellent Vintage Trek Bikes site). While the details follow, we basically switched it to 700C wheels with new tires and an eight-speed cassette (vs. 27" tires with a 6-speed Helicomatic hub), installed wider handlebars and new brake levers, and spread the rear dropouts to 135mm.

Here are the gory details.

  • New Wheels. I've written previously about the Helicomatic hub that Henry's Trek 620 came with. It was an early French attempt at a cassette hub and had a number of issues. Henry's was that the freewheel pawls stopped catching, so that he couldn't apply any power with his pedals. Meanwhile, I had a nice modern hub lying around, a Shimano Deore LX cassette hub that came with my original 1996 Marin Pine Mountain rear wheel, which began breaking spokes in May due to, I was told, corroded nipples. I'd bought a new wheel and cut up the old one; the hub was fine, and I figured it would work for Henry better than trying to resuscitate the Helicomatic.

    Paul had bought some Mavic rims and built Henry's rear wheel while I sat there fiddling with my spoke tensions. Afficiandos might notice that Henry's wheel is 4-cross lacing on the cassette side and 1-cross on the other side and wonder if Paul, an engineer, had done some extensive torque and stress analysis to arrive at this nuanced choice of lacings; actually, it happened to be the spoke sizes he had lying around.

  • Eight-speed cassette Paul built-up an eight-speed cassette. I was busy either moving tires around or reading the Gospel according to Grant (back issues of the Rivendell Reader Paul had sitting around). Why don't we make this a 650B, I'd ask, wishing I had wool seersucker socks and cotton panniers tied to my bike with broken shoelaces. Paul made some fuss about using a rare (or so he told me) 16 gear cog in the cassette. Yeah, whatever, want another beer?

  • Spread the dropouts Putting the rear wheel in with its mountain hub meant that we were going to have to spread the dropouts from a 130mm spacing to a 135mm spacing. Initially we thought, what the hell, let's just wedge the wheel in there but the stays weren't moving. Time to spread 'em.

    I'd never done this before, but Paul has. Note that this only really works with steel frames; your aluminum or carbon frames are intolerant of this technique. Now, you can go to your local bike store and ask them to do it. Or, you can do what we did, do it ourselves. Paul had the brilliant idea of using a carpenter's Jacobsen clamp to spread the dropouts. These are the clamps made of two blocks of wood with two threaded rods going through them. The nice thing is, you can tighten them in parallel. Or, in our case, spread them in parallel, using the threaded rods to move the blocks apart rather than closer together. At the medium-small size we used, one of the threaded rods goes right through the dropouts, keeping everything beautifully aligned.

    It took a lot of spreading. Steel frames have a lot of give. We had to spread it to 170mm to get it to return to a 135mm resting spacing. Once it was there, we popped the wheel in and Voila!, a new rear wheel. Again, if you happen to have an old, narrow-spaced aluminum or (more unlikely) carbon frame, DO NOT TRY THIS!


  • New Handlebars Henry's handlebars seemed awfully narrow at 36cm. Paul found some alloy 44cm on clearance for $10. These were black, but happily they were out of black and sent the more expensive silver ones for the same price. I preferred silver anyway. As is my practice, I left the bars unwrapped so Henry can see if the brake lever position is to his liking. We'll wrap it once he's content with the bars and lever positions.

  • New Brake Levers The Trek had some nice-enough Dura-Ace brake levers but the hoods were in wretched shape. Nashbar had some deal on cheap aero levers, $6 for a pair with two sets of hoods. Shoot, that's cheaper than buying replacement brake hoods alone! Henry now has aero levers and less cable clutter.

    The requisite Project of Infinite Fiddliness arose here. This frame, a 24" size (61cm), is a bit big for Henry and we don't have much stem showing. With the aero brake levers, this meant that the cable was taking a very sharp turn into the top of the front reflector bracket which also served as a cable hanger. Paul suggested that we use a different hanger, one that hung down a bit and so mitigated the sharp turn. But there's no barrel-adjuster. We hemmed and hawed, then decided to tap the dropped hanger for the cable adjusting barrel. Paul has a metric tap set, and he spent a few minutes drilling and tapping this and replacing the old one, which required removing the aluminum locknut of the Stronglight Bernard Hinault tapered-roller-bearing headset. I helpfully read excerpts from the Rivendell Reader during this. Can't have too many interviews with Japanese handlebar makers! After about 20 minutes, it was all back together and the cable bend was much more pleasing. Ahhh!

    Paul had a set of Nashbar brand cantilever brakes he'd bought for $3.96 (for all four!) he tried to flog to me but I pointed out that these were about a buck a pound and Henry wouldn't want them.

  • Tidy up kickstand. I'd wrapped the chainstays in old inner tube when I installed the kickstand. This looked pretty crappy. Paul got out some double-sided carpet tape and bits of thin foam and applied this to the kickstand plates directly, then we reinstalled it. Looks much nicer.

  • Tidy up reflector. The reflector mount on the rear rack rattled. A bit of shim work and it's nice and quiet.

  • New Tires I put on some Michelin 700C X 28 reflective sidewall tires I got from REI for $20 each. They actually look ok in daylight, and show two big white hoops from the side at night when a light shines on them. Also, they're the same size as my tires so a single spare tube can work for both of us.


I worked on my Atlantis, too. The main change was in the wheels, where a new front wheel went on built up on my 1977 Phil Wood front hub radially-laced into a Mavic rim.

  • New front wheel. In May, I had my old 1977 Phil Wood hub's bearings replaced. I bought these hubs, built my own wheels and rode them through late college and into the early post-college years, my heaviest bicycling time. I have some nostalgia for the hub, having ridden it in many states and three countries, and it feels nice to use it again. Paul built the front wheel up before I came to Cedar Rapids and it's my first radial-spoked wheel. It ought to be pretty beefy, with 36 2mm spokes. He hadn't asked about how to lace it ahead of time so I of course spent a day and a half whining about how it was going to rattle my teeth out and make my vision blurry while he extolled the many obvious and excellent virtues of radial spoking. As usually happens in these debates, once I went and rode the wheel there was no difference whatsoever from the 3-cross wheel I had on before. I am only using the Phil front hub because the rear is a 120mm freewheel hub rather than a 130/135mm cassette.

  • True, dish and tension both of the Harris wheels, my rear and the front going to Henry's bike. I'd heard some twangs from the rear wheel on the Atlantis, one of the wheels I'd bought from Harris, and suspected the spokes, which felt loose to me. Knowing that Paul has a Park truing stand and a spoke tensionometer, I didn't fiddle with it until I got to his house. Sure enough, the spokes were pretty loose and the wheel wasn't dished correctly. That's what you get for buying a set of $129 wheels. Using the truing stand and tensionometer, I pulled the wheel over where it belongs, got the spoke tensions up where they need to be and trued the wheel. I did this to the front wheel as well, which wasn't quite centered on the axle and also had loose spokes. These changes also let me get the brakes in closer. When we rode to the Starlite Lounge Sunday afternoon for golf, burgers and beer I got that delightul first 50 feet of plink-pling-pling-twang of new wheels settling in.

  • Tidy up kickstand. My Atlantis's kickstand was as shabby-looking as Henry's, so we did the same carpet tape and foam thing. I was hauling these bikes around standing up in the back of my pickup truck on their kickstands and secured with bungee cords. When I went back to my Dad's in Des Moines and lifted out the Atlantis, a piece fell off. It turned out to be a piece of the cast-aluminum kickstand that a spring pressed against. I fiddled with the kickstand and a couple of more bits fell out. Aluminum is more prone to fatigue failure than steel, and this apparently got fatigued and broke (keep this in mind if you are thinking about spreading an aluminum frame). I took the kickstand off and then nearly dropped the bike the first time I tried to stand it up in the middle of the garage. I bought a new kickstand, and installed it when I got home using double-sided carpet tape faced with snippets of chamois.

  • Extend frame pump to fit in Atlantis. I got a Zefal number 4 frame pump, the biggest they make. With the Atlantis's 68cm frame, the top tube is really long and the frame pump was too short. Paul suggested added some black PVC around the pump shaft to space out the spring and now the pump fits.


Are these bikes done yet? Nope. Henry's old Sachs-Huret Duopar Eco rear derailleur was highly-thought of in its time, but it doesn't have the travel to shift all eight cogs all the time. I figure I'll put on a Shimano derailleur and then some Ultegra indexed bar-end shifters and Henry can have indexing across all the speeds. My bike is in good shape, I might put on beefier tires for city riding, having suffered a pinch flat in Des Moines. An Esge double-legged kickstand would be nice, too, but there's no rush.

This is part of the joy of cycling, this farting around with your bike, but it's also a concern in terms of wide acceptance of bikes. It's one thing for me to think so hard about all these aspects of the bike and work to optimize spoke tensions, gearing, etc. but it's something of a pain to people who aren't into bikes. I've seen plenty of squeaky rustbuckets riding around town; I guess it's good that bikes are simple enough to work even at far-from-optimal setups, but it also means plenty of people aren't having as much fun or as good an experience as they could have because the gear isn't set up as well as it ought to be. I have to say that cars have it all over bikes here; modern cars require nearly no attention or maintenance to run trouble-free for years, where bikes are more likely to suffer flat tires, have wheels go out of true, shifters drift out of adjustment and brakes wear out of tolerance. Getting your hands dirty is either a source of quiet pleasure or just an annoyance, depending on your attitude, and not everyone's going to begin enjoying sitting around listening to the radio, drinking beer and plinking spokes to arrive at optimum tensions.

OK! IT'S SAFE FOR CIVILIANS TO RETURN TO READING

Anyway, that's it. I didn't take any photos of us working in Paul's basement with his wall full o'bikes. I'm short of Project Buddies in the Twin Cities so it's great to spend several hours plugging away on incremental bike improvements virtually nobody will notice while happily insulting each others' bikes, gear, tools, etc.

3 comments:

George said...

Neat blog entry.

I'd sure like to see what the bike looks like now.

Anybody can buy a new bike-it's cool when someone gives an old bike some love.

snorty said...

Matt, your admonition to run from the scary bike stuff had the opposite effect on me. I'm a gearhead and I really enjoy reading about how folks bring old bikes back to life. I would really like to see some photos of Henry's bike.

The spoke set up on each bike is intriguing. I don't have a clear idea about the rear wheel on the Trek looks like. The radial spokes on your Atlantis sounds a bit dangerous. Some wheels for Harleys that were set up like this had to be recalled. Anyhow, you have much less to mass to suspend, not to mention less speed.

Keep up the great work, I really enjoy reading your blog.

Cheers,
Robert

Jim said...

Radially laced wheels are very strong in pure compression - i.e. when the bike is travelling in a straight line. They don't do well in torsion, however. I doubt it'll be a problem unless you load up a front rack with a bunch of weight and take it hard into some tight corners. Most new high end racing bikes have radially laced wheels for minimal weight. But I suspect your wheel has more spokes than most of those do.

I just built (2 days ago) a cross-4 40-spoke wheel with Velocity deep-V 26" rims and a DT-Swiss/Hugi 240 disc-brake hub for the rear of my Xtracycle. I have Phil Wood 48-spoke front and rear with Velocity Dyad rims on my Atlantis. It's safe to say that I am prone to extremes when it comes to wheel strength.