Schrader time

     Everyone uses schrader valves. Yes, everyone. I know you are thinking you would never have a bike with schrader valves, you are presta all the way. But, your suspension shock and fork use them. Your car has them at all four corners, one for the fuel injection, and two on the AC system(Your home HVAC has them as well) There is even one on your water supply if you have a well.
     They are everywhere and with good reason. The schrader valve is a spring loaded poppet valve that makes it very easy to get a measured amount of gas in or out of a system. It was patented by August Schrader(most likely developed by his son George) in 1891.
     It would take another five years to develop the schrader valve cap. That's right, plastic cap, five years of R&D. Remember that next time you have trouble coming up with a plan of action.
     We have the schrader valve thanks to the bicycle. When August saw the popularity of pneumatic tires coming out of Europe he saw a need for a tire valve. Which is a little odd, because they already had a valve, other wise they would have been flat tires coming out of Europe. That valve was the presta. I have not found much on the history of the presta valve except that it seems to have been appropriated from the steam industry.
     The schrader valve has some advantages over the presta valve. They are serviceable, the core can be removed and cleaned or replaced(Some presta valves have a removable core). The valve is spring loaded and does not require pressure behind it to stay closed. Because the valve is spring loaded and the air chucks and gauges have a fitting the depresses the poppet, you can get a more accurate reading of pressure.
     A disadvantage is the hole required is slightly larger than for a presta valve. If you have a very narrow rim strength could be compromised. I feel this may have been an issue a hundred years ago when rims were made of wood or rolled from steel sheet. I have never seen a rim fail at the valve hole(Where it was not run over by a truck or tossed off a mountain side)
    You should use the valve cap. It took five years to develop, there must be some crazy technology in there somewhere. The practical reason is that it keeps crud out of the valve. If you have a little dirt in the top of the valve and then pump up the tire, some of that crud is going thru the valve and some of it might get trapped between the poppet and seat, creating a leak. You can remove the core and clean out this area but it is simpler to just keep it clean.
      The valve caps should be considered part of your suspension. The schrader valve is great for holding pressure but a rear shock at full compression can experience a spike over 3000psi. The beefy cap with its built in seal keeps that in the shock. If you lose a cap, stick a plastic one on to keep the valve clean, but replace that with a proper sealing cap as soon as possible.
     I am not going to go in to tire pressure here, that is a whole other post, but if you are concerned about your pressure, be sure to use a quality gauge(not a stick gauge). Digital gauges work best and are the most consistent, but a good dial gauge can give a decent reading. Be sure to use the same dial gauge each time so the readings will be consistent(There can be a big difference from gauge to gauge)

From my collection(of junk). Made in 1922, still works.

Pro tip, Cyanoacrylate

    

Crazy Glue, Super Glue, Quick Set, Super Bonder, Eastman 910. Cyanoacrylate is great stuff by any name. It was originally discovered when trying to develop a clear bombsite during World War II(1942). It stuck everything to everything else. Scientists at the time decided this was a useless feature and discarded it. Rediscovered in 1951 by two Eastman Kodak(There used to be this stuff called film. You would put it in a camera, take pictures with it, then pay some guy in a drugstore ten bucks to develop the film so you could see how terrible they were). These guys, Harry Coover and Fred Joyner, realized that people did, in fact, like to stick many things together. So in 1958(It took seven years?) Eastman started selling Eastman 910.
   Cyanoacrylate reacts, and sets, to the presence of water in the air(Pretty cool). That is why you need to put it on thin, so it can all react. This is also why a bottle of it becomes unusable about ten minutes after you open it. When applied to cotton, it can have an exothermic reaction producing enough heat to catch fire(Also pretty cool). Acetone will loosen cyanoacrylate as will a couple of other chemicals that sound like they may cause instant cancer.
     Cyanoacrylate is used for building models, fletching arrows, capturing latent fingerprints, and putting on fake fingernails. Guitarists use it to make their fingertips tougher. During the Vietnam war, a spray on version was used to close wounds and reduce bleeding until soldiers could be evacuated to a medical facility. It is used in place of stitches with reduced incidence of infection. It is used by college students to glue their sleeping room mates hand to his weiner, creating hilarity(Don't do this).
     In the shop, I use cyanoacrylate for a couple of things. Gluing little broken bits back together of course. And it works great if I slice open a finger or rip back a cuticle, just glue it closed and keep on working. Way better than a band-aid.
     But my favorite use for cyanoacrylate is gluing the wires of a cable end together. Sometimes after installing and cutting a cable you need to pull it back out. Getting it out is pretty easy, pushing a cut cable back thru the housing without it fraying can be tough. And some cables are pretty pricy, so you don't want to just replace them(And eat the cost) after trimming to soon. With the cyanoacrylate you can clean the cable end with solvent, apply the glue wait a few minutes and then easily remove and reinstall the cable. Even with a twisty routing the cable will stay un-frayed.
     You can also solder the cable end. This used to be a popular pro move and I still do it if someone wants me to. The problem I have found with soldering is that it makes the last half inch of the cable rigid. With modern routing, especially in frame, this can keep you from getting the cable back thru the housing and makes it near impossible to route thru a shifter.
     Go get a bottle of this magical stuff and glue a quarter to the floor in a high traffic area, it is good for hours of entertainment.
    

My bike was making a rubbing sound....

.... but it went away.

     What a great photo. Imagine how long this took. The conditions would have to be ideal. No lube, a little bit of dirt to provide some abrasive, a broken shift cable, a limit screw just enough out of adjustment that the chain did not just drop to the small ring(Think about that. The low screw was tight enough to keep the chain off the small ring but slack enough for it to rub constantly), a very tolerant rider that could handle the constant racket without checking to see what it was.
     I am not putting this up to give the guy, that brought the bike in(For another issue), a hard time. No person is an expert on every subject, and the bike still moved when pedaled, and that was all it needed to do.
     This is really an issue of gradual change. We all experience change but sometimes it sneaks up on us(Where the hell did all that grey hair come from? Wait, where the hell did all that hair go?) If your bike has a mechanical brake system, think about change, then go check them. They can stand to be adjusted, can't they? The braking material comes off so slowly that we don't notice the lever coming in further and further. Then suddenly they don't work at all. That is how we look at any kind of failure, it happened suddenly. When really it has been in the process of happening for weeks, months or years. Happens with drivetrains to. It seems like one day it is working fine and then the next it is skipping and jumping. What really happens is, from the first pedal stroke, all of those bits are rubbing against one another and wearing out. Then after thousands of miles, one tooth on one cog is worn to the point it no longer can place the chain. Suddenly your bike skips. And I know you are thinking that there are a bunch of teeth to take the load, but almost all the load is taken by one tooth and roller on each gear. On a new drive train it will be the tooth at the top of each gear on the loaded side(More about this another time)
     When a frame fails suddenly, it is usually the result of months of propagation. You might have a flaw from manufacturing. That flaw could be a poor end cut on a tube or impurity in the steel.
     Some of you remember  the spoke fiasco of the mid 2000s, where hundreds of wheels just failed(suddenly), sometimes on brand new bikes sitting in the showroom. This was caused by impurity in the stainless steel spokes. The stainless had a mix of slag and ferrous steel in it and every spot of impurity was a stress riser. The spokes worked fine as long as you left them in a box, but as soon as you laced them in a wheel and put tension on them, a crack would propagate from the impurity and suddenly taco'd wheel.
     You can have a failure from a dent caused in a crash you barely remember(Meaning the kind of crash that was no big deal, not the kind where you are knocked out)

Ignore the crack and look at the dent. It does not look to bad, just a soft smoosh.(The customer hit a tree and managed to whack the bottom of the down tube against it.) This eventually went nearly all the way around the tube. That comes back to the sudden failure. The accident happened about two months before the bike came in. But it suddenly broke.

     This is the inside of that same tube. You can see that what looked like a soft dent, created a spider web radiating in three directions. That was the failure, it just took a while for it to get big enough to notice(and I had to cut the frame apart).
     Next time something just...breaks, think back thru the time line. Look for those cues to wear and fatigue. That is how you learn to spot problems before they turn your ride in to a hike.

    

Tool Review: Drillin' Time

     Time for a little tool review. It is not about a new pin spanner or freewheel tool, this is about a drill. Surely, one does not use a drill on a bicycle you say. But I surely do.
     A drill comes in handy for lots of jobs. You can chuck a dingleberry hone(Yes, it is actually called that) on and get all the corrosion out of an old seat tube.

I'll be your dingleberry.

Drill out(another) damaged rivnut. Drill out a mangled dropout to fit a threaded sleeve. Drill a hole in a piece of wood so you can tap the brake pivot out of a Campy shifter(In order to get at the front gear carrier bolt, in order to remove the rear bolt, in order to put in, yet another, pair of G-springs)

Photo of rare, unbroken, G-Spring

     Rotor bolts, man is a drill great for rotor bolts. You have to Loctite them on, so they never just want to spin out, and when you put new bolts in they come pre gummed and you have to fight that stuff all the way down. (You do want to break them loose by hand and torque them to finish).
     You might even want to go old school and drill a thousand hoes in your bike to make it two ounces lighter(People actually do this)

Once owned by a guy with lots of free time

    
So everyone should run out and get a drill. The one to get? The Milwaukee 2407-22.

My awesome drill

 This thing is great. A real 3/8th chuck instead of a 5/16th socket fitting. The chuck is the hand tightening style so you don't have to keep track of a key and bit changes are quicker. The drill is gear driven so you can get the chuck good and tight against the gear(It locks up when static) The gear drive is two speed and the drill is variable speed so you can ease in before dropping the hammer. It has an adjustable clutch that can be set so low it will stall going in to drywall or be locked out for drilling. There is a set of LEDs that act as a fuel guage so you can tell when you are running low and the batteries are lithium ion, light, powerful, they and hold a charge forever. Comes with two batteries and a smart charger that will keep your spare perpetually topped off.

So tiny, yet so powerful.(Not the hand)

     When you pick it up, this baby feels so light you'll think it's a toy, but it will put out over 250 inch pounds of torque and really surprise you with how it powers thru just about anything in the shop.
   This drill is so great that the big boys almost never see the light of day anymore.

Sad drills that have been put to pasture.

 This is a hot tip for Christmas(I was not paid by Santa or Milwaukee for my effusive praise of this wonder piece of shop kit)

Things Not To Do, Part 1

Don't do this.

     If you don't see the problem, someone else probably takes your wheels off for you.
     If you do this someone else should take your wheels off for you.
     It is great that that tube(the chain or seat stay) is right there for you to grab and lever down the  QR. You know, get it really good and tight up against the stay. But when the time comes to get the wheel off, where do you put your fingers? See? The gap between the QR and the tube is about a 1/4 inch. Not much to work with. If it is tight enough you will need a screwdriver to lever it open.
     In our shop I have a special tool I made called the Mongoose tool. I made it by pulling the seat post out of an old Mongoose we were tossing. It has a perfect lip(The kind only cheap steel seat posts have) for grabbing the end of a QR lever and prying open without damaging the paint like you might trying to pry the lever loose with a screwdriver.
    The other issue is that when you are flat, on the side of a treeless road in July, with no screwdriver and no Mongoose tool, you don't need to add to your hassles by struggling to get the wheel off the bike. That is supposed to be the easy part of a flat repair. Save the struggling for getting that Continental tire off, and then back on, that old Matrix rim(Some of you know what I am talking about, good times)
     Just angle them slightly off the stays(or fork legs). You can still use the stay to tighten and you can get your fingers behind the lever when you need to. If you are really paranoid, you can point them aft so they don't get caught in your teammates(or random little old ladies) spokes.