Thursday, August 28, 2008

Q&A: 3-speed cable; installing bottle cages on old steel frames

Q: Saw your site online,
I have what looks like a an old Raleigh 3-speed, which my wife likes very much. I just bought a basket for her and while putting it on decided to see if I could fix her shifter. The bike was only shifting to 2 instead of 3 gears. I tried adjusting the cable, which broke, naturally. Now I'm trying to find anywhere where I can buy a new one. Any help with this will be immensely appreciated and I will forever be indebted to you.
Imploringly yours,
John

A: Hi John,
First, you should call local bike shops as this is a relatively common replacement part if they do a lot of repairs. If the bike shops don't have one, you might next try a few departments stores, which often have bike sections and sometimes even stock replacement 3-speed cables. If both those ideas don't pan out, you can order one online from http://www.bicycletoolsetc.com/
Just use their search box up top and search on the word "Sturmey" and the cables should come right up.

Also, you didn't tell me how the cable broke, but if it broke in the middle, you can usually tie it back together, or add a piece between the broken ends, as a workaround until you get the new cable. Most British 3-speeds have clips on the frame that you can move down to essentially create slack in the cable so you can tie broken ends together. But this trick won't work if it broke at the head inside the lever.

And, to adjust the cable properly, the best way to do it is to shift the bike into the easiest gear, which is first. The lever will be all the way down. In this position there should be very little play in the cable. Also, before you attach the cable, be sure the indicator rod (the piece screwed into the Sturmey-Archer hub; photo by Sheldon Brown) is screwed all the way in and then backed off slightly if needed to align correctly with the cable. Also, it's a good idea to grease the cable where it runs inside housing and under or over pulleys. And, when the cable is adjusted correctly and the bike is shifting properly use 2 pairs of pliers to lock the cable adjustment by tightening the knurled lockring on the indicator against the end of the cable. That way you won't lose your adjustment over time.

You can learn lots more about adjusting Sturmey-Archer 3-speed on Sheldon Brown's awesome website here: http://www.sheldonbrown.com/sturmey-archer.html

Hope this gets you going,
Jim
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Q: Several of my friends and myself with old-school 70's steel frames(Reynolds 531 DB, etc) are thinking about getting water-bottle fittings installed. The local shops want to drill a hole in our frame tubes (down- or bottom-tube) and insert a pop-rivet nut. That meets our need but we're all worried about putting holes in our old, thin-wall tubing.

Any ideas, anecdotes?
...0ran....

A: Good question, Oran. If you look back at quality steel road bikes made before around 1970, you'll see that very few framebuilders ever installed braze-on water-bottle bosses on the frames. Instead they insisted that you put clamps on the tubes to hold your bottle cage on. This looked ugly, but the framebuilders said that if you drilled holes in the frame tubes it would cause them to break. (It's usually not a good idea to drill holes in structural frame members like bicycle tubes because the stresses of riding can gradually work on the edges of the hole and create shear points and over time you can have cracking or tube breaks that start at that hole, the weakest point in the tube.) It's important to understand that butted steel tubes are weakest in the center of the tubes, which is exactly where you drill the holes for the bottle braze-ons. Here, a quality steel frame tube could be less than .5mm thick.

Slowly the concern over the tubes breaking changed, though, and by the mid to late seventies most steel bikes came with bottle bosses brazed onto the frames, usually on the down tube only, but later on both the down and seat tubes, and then even later, also beneath the down tube on touring bikes (usually used to carry fuel for your stove). The reason this happened was because the braze-ons used and the installation of them addressed the issue of the holes weakening the thin-wall tubing.

The braze-ons were designed to reinforce the tube at the hole. Most were threaded inserts with a reinforcing rings or tabs that rested against the tube and when the braze-on was brass or silver soldered in place, it actually doubled, or more than doubled the thickness of the frame tubing at the hole making it plenty strong. This is the key reason they worked: they reinforced the tube and they were soldered in place.

That gives you some background. Rivet-type bottle bosses came along with aluminum bikes and they usually work fine on them, but I'm not sure I'd trust them on a nice old steel frame. I'm sure they would work for a while and maybe forever if you don't ride that far or all that hard. But, I'd worry that since they aren't actually brazed to the frame, that the holes in the frame could develop stress cracks over time, which could travel outward and into the tube. I've just seen too many broken steel frames from cracks like this, so I'd worry about it. If it was a heavy-duty steel frame it might work fine. But, a nice Reynolds double-butted frame has thin, thin tubing.

I'd recommend having a local framebuilder braze some bottle bosses on for you instead, or going low-tech and just using boring old bottle-cage clamps. The only drawback to having bottle braze-ons installed is needing to repaint the frame at the braze-ons. (Some people just touch it up with primer and don't worry about the looks - or, if you're good with painting, you might be able to match the original paint finish pretty closely and almost make the bottle braze-ons disappear.) But, you'd at least have a permanent high-quality job that you could rely on - and your frame wouldn't break.

I hope this helps and thanks for keeping those classic bikes on the road, Jim
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Thursday, August 21, 2008

RECALL NOTICE: Cervelo Wolf SL fork

Folks - If you ride a Cervelo bicycle that's equipped with a Wolf SL fork
made by True Temper Sports (I do), please stop riding it immediately and
bring it to your bicycle dealer for replacement. The Wolf SL fork has been
recalled due to several reported failures leading to crashes and injuries.
Cervelo says, "The recalled forks have a clear coating over black-painted
carbon fiber, with the words "Wolf Superlite" and related logo just below
the crown on each fork leg, and the words "SL" on each leg above the fork
blade dropouts. There is a True Temper CRTMC logo on the inside of both fork
legs. The recalled forks could have been included on the following bicycle
models: R3, R3 SL, Soloist Carbon, Soloist Carbon SL, and certain P3 Carbon
framesets and complete bicycles."

Here's a link to Cervelo's recall page, which has photos and more:
http://www.cervelo.com/wolfslrecall/default.aspx?lang=en
Here's a link to the BikeBiz blog that has links to some examples of broken
Wolf forks with photos:
http://www.bikebiz.com/news/29731/Cervlo-alone-recalls-third-party-fork

Wednesday, August 20, 2008

NEWSWIRE: Crankset Transmissions


Most multi-speed bicycles rely on an elegantly simple and super-light device called a front derailleur that shifts the chain across the different size chainrings to provide a wide range of gearing. The primary disadvantage of this system is a different chainline for each chainring, which can result in dropped chains, chain suck and sloppy shifting. The need for several size chainrings can also cause clearance and suspension issues on certain mountain bikes. Recently, component maker TruVativ leaked news of its HammerSchmidt transmission, a crankset that solves all these issues by providing 2 gears from a single chainring crank that works with internal planetary gears, which is similar to how 3-speed hubs work. There's an excellent report on this ingenious new transmission, complete with videos, here. However, TruVativ isn't the first to invent something like this. There were front transmissions dating back to the turn of the century, and there's at least one other modern one, made by Schlumpf Innovations. Designed to work on road and mountain bikes, Schlumpf's Speed-Drive and Mountain-Drive have a clever shifting technique: you tap the crankarm cap with your heel to shift gears! Learn more on this cool crank here.

TruVativ's HammerSchmidt and Schlumpf's Speed-Drive

Sunday, August 10, 2008

Q&A: strong wheel, finding old bike parts, fixing a foot brake

Q: Hi Jim,
I'm a large male - twenty stones (280 pounds) - and I use my cycle to
and from work about eight miles a day most along a cycle path. I also
use it for pleasure. But the problem I have is that in the past twelve
months I have buckled three rear wheels. I have been told it is
because of my weight and that I should get a reinforced wheel. Could
you give me any advice?

Many thanks
John

A: Hi John,
My recommendation is to bring your bicycle to a good local bike shop
that has a reputation for high quality wheelbuilding. If you ask other
cyclists you should be able to find out who builds great wheels at the
local bike shops. A good builder will look at what you've been riding
and listen to how you use your bike and design a custom wheel that
will hold up for you. There are many options from different spoke
gauges, to more spokes, to heavy-duty rims. A good custom builder will
pick just the right components, build a very nice and strong wheel and
then guarantee his/her work, too, so that if you have a problem in the
future you will get your wheel fixed for free.

That's what I recommend and I'm sure you'll get a dependable, nice riding wheel,
Jim
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Q: Jim,
I have a 1936-7 Roadmaster classic cruiser bicycle that I reacquired a
couple years ago after my Mom passed away. I am trying to restore it
to it's condition at my boyhood. My step Father did some changes to
it a several years back
discarding the fenders and apparently misassembled the coaster brake. I
have downloaded the exploded diagram of the brake and find that the clutch
retaining ring part# 110B1/2 is missing. I either need a replacement ring
or the specifications for it so I can make a replacement. Also I would like
to purchase replacement fenders.I hope that you can help me with these items.
Sincerely,
Richard

A: Hi Richard,
Morrow hubs and parts for classic old cruisers are getting a little
hard to find. I think your best bet would be to search eBay.com for
Morrow hubs or wheels with Morrow hubs or a complete bike with a
Morrow hub that you could buy and rob parts from. Similarly, you might
find a bike with the right fenders, too, if you're lucky. You might
also try contacting the guys on the www.thecabe.com website and see if
any of them can help you out. Maybe they have an old hub or some
spare parts. Another way to find vintage parts is at bike/car
swapmeets if you're lucky enough to have one in your area or are
willing to travel to one. One of the biggest is the Hershey swap meet,
which takes place in April each year. It's primarily for antique car
buffs, but is known for having loads of two-wheel deals, too, since so
many car collectors love bicycles, too. But, any car meet might have
vintage bicycle stuff, too, so they're all worth checking out when
you're hunting for parts. You might also try the folks that run the
Copake bicycle auction each year: http://www.copakeauction.com/

I think one of these things will get you going with just a little luck and
persistence. Good luck!
Jim
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Q: Hello Jim,
Maybe you will have a possible answer that I just can't find on the internet.

I'm having a problem with a Shimano CB E110 coaster brake hub that
came with a single speed bike I purchased about a year ago. I've been
working on bikes as an enthusiast for about 30 years, but not much on
coaster brake (foot brake) bikes.

The Shimano CB worked fine until recently, when it developed a 'clunk'
and 'release' sort of response to pedaling backwards to engage the
brake. It brakes just fine however. Mostly annoying, but probably not
a safety problem. I hope. That's why I'm asking around as to what it
might be.

I've had it apart, put in a new spring, new bearings, new grease (high
temp), and adjusted it perfectly. No play, no binding!

But, now it's starting again, just a little bit though. I can't get it
to 'clunk' and 'release' on the bike repair stand, only in operation.
My LBS owner and friend suggested possibly the front ashtabula
chainwheel was moving a bit because of looseness (NOPE), or that the
rear cog was worn and chain was catching and releasing (NOPE - all
brand new and not that many miles on them). Any ideas?

Thanks much,
Phil

A: Hi Phil,
It sounds like you've checked the right things. I would have checked
the ashtabula sprocket, too, that was a good suggestion. Did you check
that the rear cog is not damaged? It attaches to the hub with small
tabs on the inside hole in the sprocket. These tabs can get worn and
if so the cog can slip under pressure and then release as the damaged
tabs refind their respective slots in the driver in the hub. You'd see
this on the cog but only if you look closely. There can also be
snapring problems that allow the cog to move and can cause problems.
You might check those things - that the tabs aren't worn and that the
cog is sitting securely and stays put on the hub driver. A new cog
would fix these issues, maybe a new snapring, too.

The other things that you didn't mention are the brake shoes and the
hub shell. These hubs are pretty basic and not too terribly tough. The
brake shoes can wear funny and that can make them jam a bit. You could
compare yours to new ones and see how they compare and put in new ones
if yours look worn or shaped funny. And, you should check the inside
and the bearing surfaces of the hub shell to see if you can spot any
small cracks or bearing wear marks and even scoring inside that could
be caused by lack of lubrication or bad, worn brake shoes or grit,
etc.

Oh, one basic thing some people don't realize: you should lube all the
parts up with a decent bicycle grease. If you run it dry or nearly
dry, it's sure to jam. You need to lube it good.

Maybe something here will help. Good luck!
Jim
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