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1.Width Matters Too
Where is it written that: "All roadies shall ride 700x23 tires"?
We're on frames of carbon, steel, aluminum, titanium and mixes of these materials, which tells me that we all beg to differ. Then why is it that 23-mm-wide tires have become the unchallenged norm? We should choose tire width based on body weight and several other factors, not just by going with the industry flow.
It's rare to find a new road bike fitted with anything but 23s. We ride this size by default and some of us suffer the consequences. If you buy into my advice to lower tire inflation to 85-100 psi, then you probably realize that you, at 165 lbs. (75 kg), and your 215-lb. (98-kg) pal can't ride the same size tires at the same pressures. Big Dude will pinch-flat at 90 psi when the going gets rough.
So while you're flying with a smile over cracks and crevasses, Big Dude is fixing another snake bite and sticking pins in his Uncle Al doll. I think I'm feeling a jab in the ribs right now.
The solution is simple: Increase tire width if you're heavier so you can enjoy the comfort and handling benefits of lower pressure.
Some tire manufacturers understand the need. They offer their premium models in sizes from 700x20 to 28. Continental, for example, makes the venerable Grand Prix in 20, 22, 23, 24, 25 and 28 mm. Michelin's Pro 2 Race comes in 20, 23 and 25 mm. But too many companies make their top-shelf tires no wider than 23.
The belief is that wider tires increase rolling resistance. It simply isn't true. Testing shows that fatter rubber rules when it comes to lowering drag. One recent example was published by Bicycle Quarterly magazine in "The Performance of Tires" (Vol. 5, No. 1, Autumn 2006).
Let me suggest an approach to greater riding enjoyment and less side-of-the-road voodoo:
- If you weigh 170 lbs. (78 kg) or less, use 23-mm-wide tires. (I can't recommend 20 mm, but if you're really light and want to use them, knock yourself out.)
- 170-180 lbs. (82 kg), use 24 (Conti makes 'em) or 25 mm.
- 180-210 lbs. (96 kg), use 25 or go to 28 mm if you ride on crappy roads.
- Over 210 lbs., use 28-mm tires. Your big power will cancel the bit of extra weight.
If you follow these size guidelines, you can safely inflate only to 85-90 psi front and 95-100 psi rear and enjoy a quicker and more comfortable ride.
2.Refill your tubes with air when you get back home after fixing a road flat with a CO2 cartridge.
Butyl rubber dominates the market and is used for almost all tubeless tires and bike tubes as its permeability to air is incredibly low — butyl tubes have only 10 percent the leakage rates of natural latex rubber tubes.
Permeation by diffusion predicts gas leakage rates proportional to the inverse of the square root of their molecular weights. Using air as a reference the predicted leakage rates for common gases are: helium 2.7, air 1.0, nitrogen 1.02, oxygen 0.95, argon 0.85, carbon dioxide 0.81.
It turns out however that the leakage rate of CO2 is huge, and the reason is that it is actually soluble in butyl rubber and is thus not constrained to normal permeation loss, it can transfer straight through the bulk rubber resulting in severe tire pressure loss on the order of a single day. CO2 is not likely to be replaced by argon or other gases in refill cartridges, however, because CO2 is much more easily liquefied than other gases and can be contained in a moderate-pressure cartridge in a patch kit. An analogous cartridge holding N2 or argon (non-liquified gas) would be dangerous and would require a thick (and very heavy) steel-walled storage vessel. A reference dealing with CO2 transfer through latex rubber sheds light on the loss process.
3.Riding in the rain.
Difference is, my shoes were dry the next day. Why? Because I am a rain god. Yes, a lifetime of poor judgment has made me an expert in bad-weather cycling. And now that winter is approaching the northern hemisphere, it's time to wring this knowledge from my soggy brain into the catch-basin of your eager minds.
Q: How do I dry my shoes?
A: Stuff them with crinkled-up newspaper. After a couple of hours, replace the wet wad with another dry one. Shoes will be mostly dry by morning. Use the editorial pages, since all that hot air cuts drying time by 30%.
Q: What about eyewear?
A: Go with amber- or yellow-tinted glasses. Not because they improve clarity in gray conditions, though they do. The real benefit is that they make the day seem brighter than it is, convincing you to add another loop and ignore that funny funnel-shaped cloud on the horizon. More miles, baby.
Q: Footwear?
A: Wool or polypro socks, followed by shoes, followed by plastic bags with holes cut out for your cleats, followed by booties. Don't forget to seal the tops of the booties with duct tape to keep water from running down your legs and into your shoes. Removing the duct tape from your skin afterward is painless because you remembered to shave your legs, right?
Q: Rear fender?
A: Tough call. Doesn't really keep your butt dry if it's raining anyway. But it will prevent dirty water from spraying the face of the rider behind you. So I say: no fender. Take that, wheelsucker
4. Ease Up to Enable Uphill Shifts
When you shift from the big to small chainring on a moderate hill, life is beautiful -- the chain drops into the lower gear range you need. But when you try this shift on a steep grade, the chain won't budge. It just rubs the derailleur cage and refuses to leave the big ring. On bikes with triple chainrings this uncooperative shift occurs when trying to go from the middle ring to the granny. You might suspect a mechanical problem, and it could be. But more than likely it's a technique problem and something you can work on during your next hilly ride. In all cases, the cause is the chain being so tightly wrapped around the bigger ring's teeth that the derailleur can't pull it off. The bike slows, you push harder to keep moving, and there's no chance that chain is going to budge.
Of course, one solution is simple: Anticipate shifts better so you can make them before you're applying heavy pedal pressure. But if you blow it (we all do occasionally) and need to shift under load, first pedal firmly for several strokes to give the bike more momentum. That's not easy on a steep climb, but it's the price you have to pay. Next, let up pedal pressure just as you make the shift to the small ring. Keep the pedals turning, of course, but with only moderate force. This should allow the shift to take place as nicely as it does in normal conditions. Then you can resume strong pedaling to get up the hill. It's a coordination thing. Once you get the knack, you can make that obstinate shift in a single light pedal stroke and you won't lose much momentum.
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Safe and Courteous Group Riding |
Based on the principles taught in the League of American Bicyclists Bike Ed program.
Cycling with friends, traveling rapidly and safely with confidence in your companions, is a joy. However, there is a certain cycling etiquette, or Rules of the Road, of which you should be aware whenever cycling in a group.
Getting along with other bicyclists
1. Be Predictable - Group riding requires even more
attention to predictability than riding alone. Other
riders expect you to continue straight ahead at a
constant speed unless you indicate differently. Being
predictable will make motorists happier and keep you
safer.
2. Use Signals - Use hand and verbal signals to
communicate with members of the group and with
other traffic. Use hand signals for turning and
stopping. Extend left arm for left turn and right arm
for right turn. Put left hand down at the side with
fingers slightly spread for STOP. When moving left
to avoid an obstacle such as a parked car or debris
signal by extending your arm to the left to tell cars
and cyclists behind you that are moving left.
3. Give Warnings - Warn cyclists behind you well in
advance of changes in your direction or speed. To
notify the group of change in path, the lead rider
should call out "left turn" or "right turn" in addition
to hand signals.
4. Change Positions Correctly - Generally, slower
traffic stays right, so as a rule pass other cyclists on
their left. Say "on your left" to warn the cyclist ahead
that you are passing. If you are approaching someone
on the right or need to pass someone on the right, say
"on your right" clearly since this is an unusual
maneuver.
5. Announce Hazards - When riding in a group,
most of the cyclists do not have a good view of the
road surface ahead, so it is important to announce
holes, glass, gravel, grates, and other hazards. The
leader (or rider in front of a group) should indicate
road hazards by pointing down to the left or right and
call by "hole", "bump", "road kill", etc. where
required for safety.
Getting along with motorists
1. Watch For Traffic Coming From The Rear -
Since those in front cannot see traffic approaching
from the rear, it is the responsibility the riders in the
back to inform the others by calling out "car back".
Around curves, on narrow roads, or when riding
double (side-by-side) it is helpful if those up front
call out "car up" to those in the back. When you hear
"car back" move right to become a single file line. Be
courteous to motorists.
2. Watch Out At Intersections - When approaching
intersections that require vehicles to yield or stop, the
lead rider will say "slowing" or "stopping" to those
behind of the change in speed. Do NOT say "clear" to
indicate no crossing traffic. This is a dangerous
practice that should be abandoned. Each cyclist is
responsible for verifying that the way is indeed clear.
3. Leave A Gap For Cars - When riding up hills or
on narrow roads where you are impeding faster
traffic, leave a gap for cars between every three to
four bicycles. That way a motorist can take advantage
of shorter passing intervals and eventually move
piecemeal around the entire group
4. Move Off The Road When You Stop - Whether
you are stopping because of mechanical problems or
to regroup with your companions, or just shooting the
breeze with someone you haven’t seen in a while,
move well off the road so you don’t interfere with
traffic (both cars AND other cyclists). When you start
up again, each cyclist should look for and yield to
traffic.
5. Ride One or Two Across - Ride single file or
double file as appropriate to the roadway and traffic
conditions and where allowed by law. Most state
vehicle codes permit narrow vehicles such as bicycles
to ride double file within the lane. Even where riding
double is legal, courtesy dictates that you single up
when cars are trying to pass you.
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