Sharpen a step bit?

On Thu, 19 Apr 2012 14:13:47 -0400, Leon Fisk


FWIW, I raced road sprints in the mid-'60s with the Somerset Wheelmen, and I followed the standard procedure at the time: soak overnight in kerosene (I had a motorized vibrator I made from an old fan motor with an eccentric weight, a steel baking dish, and two layers of hardware cloth on the bottom to raise the chain above the dirt). Remove chain from baking dish, wipe with rag, re-install.
That was for racing (Cinelli and Frejus bikes; Campy chains). For touring and training use, it was followed by a drop of 20-weight machine oil on each joint.
I'm not saying that's the best procedure, but, again, it was standard practice, and my current chain(s) on my Super LeTour are over 20 years old and going strong. I keep two chains for touring use. I'd never switch a used chain on used gears for racing.
--
Ed Huntress

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On Thu, 19 Apr 2012 14:29:05 -0400

<snip>
Only racing I've ever done is getting back home for beer and munchies :)
I used to put on ~5000 miles a year riding a "tank". Mediocre mountain bike with City Slicker 2.25 inch tires, fenders, special handle bars... My aim was exercise and not worrying about crap in/on the road. Plow over curbs, railroad tracks, storm grates, loose gravel/sand... I don't think wax would be the best choice for racing, too much friction. But then I'm not racing and I doubt you are anymore either. Unless you are riding in wet conditions wax works well. Sheds gritty stuff good too. They have some commercial formulas or you can brew your own. I started out with a commercial chain wax but when it got low I just started adding canning paraffin to it. If you had some TFE powder, or graphite that would be good to add too.
My front chain rings are worn out, shot. I filed them down once because of chain jump (biggest front ring was jumping). Put an old chain back on because it was in better shape than the one I was using. Chain doesn't jump anymore which is good enough for me. That chain ring only has ~30,000+ miles on it. Working on my third or fourth rear cluster. Lost track a few years ago when I gave up riding so much. I always felt an old sloppy chain shifter better than a new, tight one.
I used to be pretty anal keeping the chain, sprockets, bearings up to snuff but unless you're in competition it really isn't all that necessary. I became curious in my last few years just how far I could go (mileage) before I had no choice but to make repairs. Nowadays the bike is winning...
--
Leon Fisk
Grand Rapids MI/Zone 5b
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On Thu, 19 Apr 2012 15:10:24 -0400, Leon Fisk

It sounds like you're a serious cyclist, Leon. All of those miles probably give you some real insights.
I never laid down miles like that. I did an AYH Century back in '66, after the racing, and then it's been casual touring, mostly with my wife. I am a bit anal about replacing and re-packing bearings, etc., but that's part of the fun for me. I really like tuning up a good bike.
--
Ed Huntress

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On Fri, 20 Apr 2012 11:19:11 -0400
<snip>

What else can you do while racking off exercise miles. Listening to NPR or Rock & Roll helps some :) But I lost my mojo several years ago when my Dad's Alzheimer's became too much and winter bit back. Haven't rode diddly squat since other than several hundred last fall because my right foot developed some sort of problem that stopped my running on it.

I used to repack bearings every year too, until I got lazy. Now I figure with a decent grease pack (lots of grease, not a wimpy amount like racing) you should be good for 3000-5000 miles easy enough. You'll notice wear spots on the cones first. You can mark the cone, turn the worn spot up and be in good shape. I've done that several times already and replaced the cones a couple times too. New cones are cheap enough, getting the right sizes though for older bikes can be a pain. Old dust caps don't always fit and new ones (dust caps) aren't the right outer size. I've got a lathe now, which could help with that woe if I get the urge. But a good cleaning, lots of grease, some new balls and believe me some really bad looking cups and cones will still get the job done for many, many miles.
You think the cones are hardened clear through or just case? If clear through I would be sorely tempted try hitting them on the lathe and try taking off the worn spots. Couldn't make them any worse :) The way they are worn though makes me think that they are caseharden.
I saw an article awhile back where a guy was using his CNC Mini-Mill to whip out custom chain rings for $$. Pretty sure they were aluminum but I doubt that would bother anyone wanting one bad enough to get it custom made.
--
Leon Fisk
Grand Rapids MI/Zone 5b
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On Fri, 20 Apr 2012 16:06:27 -0400, Leon Fisk

I don't know, and I've considered doing the same thing. I haven't tried it, though.
Bicycle bearing cups are not as hard as one might think. I've seen comments that they run around Rc 60. The big issue with ball bearings and cups is not hardness so much as resistance to spalling. Given that hardness and the spalling issue, I'd be surprised if they're case hardened. But I don't know for sure.

I don't know why one would, given the variety of materials available today.
BTW, I converted my son's Raleigh off-road bike to something like yours last summer, with narrower road tires. He commutes from Georgetown Univ. to his job in downtown DC on it, and didn't want skinny little tires. There's too much broken glass on the city streets.
I tried to tell him about using one's gloved hand to wipe over lace-up tires every few seconds to remove glass and steel splinters, like we did on racing bikes 45 years ago, but he didn't want to hear anything about it. He thinks we were crazy. d8-)
--
Ed Huntress

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On Sat, 21 Apr 2012 13:07:39 -0400, Leon Fisk

Not me. I've even thought about how I would do it: a cast-in-place epoxy lap, filled with fine silicon carbide abrasive.
At least, that's the first thing I'd try. I've had good luck with epoxy laps in the past. It might require something more compliant; maybe a cast-in-place glob of filled polyurethane or silicone. You'd have to be careful not to overheat them.
If you're nutty, then we're both nutty. d8-)

If you do, please let us know. I have a feeling that a well-done job in a lathe would make a more perfectly centered cup with a better surface finish.
But if it's nitrided, you'd go though the nitriding. If it's carburized, it's anybody's guess.
Spalling is a problem with all kinds of ball bearings because the very high pressure resulting from point contact can put a fatiguing load on the balls and the races. That's how they usually fail in normal use. Spalling usually is a compression failure that results from appoaching the elastic limit of the material through many cycles. Then the failure quickly becomes catastrophic, sometimes cracking the balls, and it can be hard to tell how it all started.
Unless the bearing races were abused and brinelled, it's usually spalling.

So far he's had no flats, and he's friends with a local bike shop, so it's in his hands now.
I was surprised at how well it rode with the narrower road tires. I ride a lightweight with 1-1/8 x 27 tires (they're becoming hard to find -- I'll switch to 1-1/4 the next time), and I thought his bike with 80 lb. of air compared favorably to mine with 100. Not quite, but close enough.

Well, that was mostly for training. I only rode sprints, one to five miles, never long events. I was a quarter-miler on my high school track team and I didn't want to do any endurance cycling while I was trying to stay trained for speed. My track coach was pissed off at me for cycling anyway. And he went ballistic when I trained for my Red Cross Senior Lifesaving card. d8-)
Long-distance racing cyclists used the glove-on-tire method, though, at least in the old days.

Hmm. That sounds like a couple of times I got a flat and found that my tube of patch adhesive had dried out.
--
Ed Huntress

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wrote:

clear
try
they
was
that
You guys do realize that they don't use bearings like that any more, don't you? I took my 8 yr old mt bike in to have it worked on. They really couldn't. I had to offer my freewheel removing tool. Now everthing has cassettes for the gears and sealed bearings for the wheels and bottom brackets. Shades of Phil Wood - circa 1968.
We used to measure our chains every few months. When the length of the chain had increased over 1/16, time to replace or you would wear out the chainwheel. The primary problem was squeezing out the wax that was packed at assembly. The secondary problem was washing it out with solvent.
Ed, I'm surprised that being a sprinter out east, you didn't fall prey to the theory that oil slowed you down. Lots of the east coasters used to run their bottom brackets dry and change the balls every few weeks.

my
spurt
say
They
misc
up
racing.
Of course, there's the story of the old time 6-day rider who had a ring he wore that had a sharp point on it so he could "flat" his tire and get some rest time during the race.
A fresh patch kit, square of something tough

capable
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On Mon, 23 Apr 2012 22:29:18 GMT, Sternpaddler

But my bike is a 30-year-old Schwinn Super Le Tour. No problem. <g>
I've seen those cartridge-type hubs, and they look very slick. I do have a tube of Phil Wood Waterproof Grease I bought around 1985, though. I use it on my plumbing faucets...

Uh, you're not quoting me there. That was someone else. Somewhere in that thread I mentioned that we cleaned our chains in kerosene, wiped them dry, and then ran them without oil except for training. Before a race, we'd clean the oil off with kero again.
When I had Campy components, I didn't oil the bearings for racing, either. Even the jockey wheels on my Campy (Campagnolo) derailleur had adjustable-cone ball bearings. They were hardened steel jockey wheels with no teeth. I ran them dry for racing, too. That bike had a lot of ball bearings.

Yup.
I can believe it. My dad raced in the 6-day races in Atlantic City. He was a lot tougher than I was. Jeez, what an ordeal.
--
Ed Huntress

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It amused me to see the gung ho cyclists at work with every thing you can think of to reduce the effort, ride at lunch time to get exercise.
Dan
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On Fri, 20 Apr 2012 09:26:42 -0700 (PDT)
<snip>

Snort! I know exactly what you mean. Even more amusing is seeing them get stopped with a flat tire or trying to negotiate something rough like a railroad tracks that some gnarly fat road tires would just shrug off.
--
Leon Fisk
Grand Rapids MI/Zone 5b
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http://www.themadfermentationist.com/2008/10/ageing-wine-with-ultrasonic-waves.html
Fly cut with a diamond point.
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