Bicycle Maintenance: Tires and Flat-changing Part 2 - AQ

This is Part 2 of the 3-part series on Bicycle Maintenance: Tires and Flat-changing.

In Part 1, I talked about what to expect in my flat-changing clinics, held monthly and hosted by B+L Bike and Sport. Here are some of the questions that come up in my flat-changing clinics. Please feel free to add your own questions in the comments. :)


WHEN IN THE COURSE OF CHANGING A FLAT...

Do I need to take the whole tire off?

No. You only need to take one side of the tire off so that you can remove and replace the tube.

What are the advantages to removing the whole tire?
Facilitates finding the thing that made you flat.
Removing the tire entirely will make it easier to find the glass, thorn, piece of wire, etc. Sometimes the object will remain in the rubber of the tire, slightly poking through the inside, just waiting to flat your new tube. With the tire removed, you can practically turn it inside-out.

Is there any disadvantage to removing the whole tire?
Remounting it in the wrong direction. 

Tires are often designed to roll best in one direction. Unless you know the direction of rotation, which is sometimes stamped into the sidewall of the tire, you need to either 
a) pay close attention to decals and logos when you removed the tire, i.e., logos match up to the cassette /skewer nut side or the skewer lever side, or
b) know how to read the directional tread of a tire.

"<= ROTATION" is stamped into the sidewall of many tires.

TUBES 

What do all those numbers on the tube box mean?

Example: 700 x 18-28, 48mm  (road tube)

• 700 = roughly 700mm rim diameter
• 18-28   Number of mm wide the tube will comfortably inflate. If the tire is narrower than 18mm, there will be too much flabby tube inside it. If the tire is wider than 28mm, the tube will be stretched too thin.
• 48mm  length of the presta valve on a road tube. Deeper rims require longer valve stems. A short valve stem inside the rim may not allow you to attach the pump to inflate it.

Example: 26 x 1.9-2.125  (mountain bike tube)

• 26 = 26" diameter rim
• 1.9 - 2.125  Number of inches wide that the tube will comfortable inflate.

How do I know I have the right size tube?

Easiest way: take your tire to the bike shop and tell them you need a spare tube. When you remove the tube from the box and put it in a plastic bag, tear off the end of the box with all the numbers and put it inside the bag with the spare tube.

TIRES

Are bike measurements in inches or metric?
Road bikes are most commonly measured in metric, mountain bikes in inches.

What is the "bead" of the tire?

The bead is the edge that hooks into the rim and holds the tire onto the rim. Tire beads are either wire or kevlar.

What is the difference between wire or kevlar bead tires?

Wire bead  

• often less expensive 
• harder to mount onto rims 
• better for 230+ lbs riders (because the bead stays in place and won't blow off the rim) 
• adds 50-75g in rotational weight, which is fine for flat terrain, but more work in hilly terrain.

Kevlar bead 

• often more expensive than wire bead 
• easy to mount into rims
• fold-able (you can carry one in your back pocket if you need to)
• reduced rotational weight

How much air do my tires need?

Every tire is stamped with a recommended inflation. Road bike tires are high pressure, low volume, and are generally inflated between 95-125 psi. 

Road bike tire recommended inflation: 115 PSI / 125 PSI

Mountain bike tires are low pressure, high volume, and are generally inflated between 30-50 psi.

Mountain bike tire recommended inflation: 36-65 PSI 

Why are some road tires perfectly slick and others have ridges (tread)?
Perfectly slick road tires are most often used by racers, having the least friction and drag. Tires with more tread provide better grip and are better for directing water or mud away from the center of the tire. Ask at your local bike shop which tire is best for your riding style and goals.

MISC

Is the rim and the wheel the same thing?
No. The rim is only the hoop part with the holes in it. The wheel is made up of the rim, spokes, hub, etc.

What is presta and schrader?

Tube valve stems are either presta or schrader (looks like the car tire).

presta valve in a mountain bike wheel

Unscrew the top (little gold piece) to inflate. Be sure to tighten it back down.

How often do I need to pump up my tires?

Check tires before every ride. 

Properly inflated road tires should feel completely solid. If you can make any depression with your fingers in the sidewall at all, you need air. Use a good floor pump and knew for certain how much pressure is in your tires. 

If road tires are to be harder than an apple, mountain tires should be a bit softer than an orange. You should be able to depress the sidewall slightly. 

If you have additional questions or are curious about tubes or tires, please see Sheldon Brown's website. Although Sheldon is no longer with us, his site is maintained by volunteers and remains a great resource for cyclists.

Next week I'll have Part 3: What's in your saddlebag? Items you should have with you when you ride.

Bicycle Maintenance: Tires and Flat-changing (part 1)

This is Part 1 of the 3-part series on Bicycle Maintenance: Tires and Flat-changing.

When I first started cycling, my mechanic in New Jersey encouraged me to attend a flat-changing and bike maintenance clinic put on by the parks department. I remember following all the steps the instructor told me, but still being so confused, and feeling like I only got through the flat-changing part because someone more knowledgeable than me was there to help.

Since that clinic in Feb 2003, I've tried to learn as much as I could about bikes and bike maintenance. Being something of a compulsive teacher, I naturally have to pass on what I've learned, so I started teaching flat-changing clinics with women as the target audience.

Now I teach a flat-changing clinic at B+L Bike and Sports once a month. This past Sunday afternoon, I taught at the Solana Beach store where we had nine women attend. It was a great afternoon!

Jenny and Robbin watch as Monica pulls the tube out of the tire in a simulated flat.

It's important that everyone actually work on a bike and not just spectate. Doing it yourself boosts your confidence, and reinforces the notion that you can, in fact, do this yourself. We always work on rear wheels, with at least ten minutes spent removing and replacing the rear wheel, until everyone is comfortable doing so. As with most things, there are tricks to making removing/replacing a rear wheel easy. 

 Monica continues working on her tire as Bev (background) looks up from her work.

Depending on space, there will be 4-6 bikes to work on. Attendees will work singly, in pairs, or even in groups of three to get the job done. Taking turns, everyone gets a chance to practice removing and replacing the rear wheel, removing the tire, getting the tire back onto the rim, and inflating the tube with CO2.

Heather and Megan (left) and Patti and Jennifer (right) work in pairs  to install the tube.

Everyone gets a chance to practice using CO2, thanks tosupport by Genuine Innovations. I remember being somewhat skeptical myself (read: afraid of it) at first. But once I realized how easy it is to use, and how I could eliminate ten minutes or more of exhausting frame pump arm work on the side of the road by using a CO2 cartridge that costs as little as a vanilla latte, I was sold.

Jan and Bev line up the CO2 to inflate the tire. Special shout-out to Genuine Innovations for providing MicroFlate Nano heads and CO2 cartridges for the women to practice with.

In part 2 of the blog Bicycle Maintenance: Tires and Flat-changing, I'll answer 
frequently asked questions, including:

• What do all those numbers on the tube box mean? 
• How do I know I have the right size tube?
• Do I need to take the whole tire off?
• Why are some tires perfectly slick and others have ridges (tread)?
• Is the rim and the wheel the same thing?

Please feel free to post your questions below! If I can't answer it, I'll find the answer from someone more knowledgeable than me.

Patti checks to make sure the MicroFlate head in lined up square to the rim for best air flow.

Thank yous are in order to all the attendees of my most recent clinic in Solana Beach: Monica and her friends Robbin and Jenny, Bev, Jan, Heather, Megan, Patti, and Jennifer. Thanks to the guys at B+L Bike and Sports Solana Beach: Tom, Scott, Gisan, and especially Kevin who stayed late for us. Thanks to Mark of B+L Bike and Sports who invited me into his shop and is hosting these events. And big thanks to Genuine Innovations, who supplies the MicroFlate Nano heads and the CO2 cartridges we use in class. These San Diego Flat-changing clinics exist because of your efforts.


Next clinic:
Sunday, 5/20/12, 3:45 PM
B+L Bike and Sports in San Diego (Rosecrans).
RSVP on Meetup.com

 

Women's Mountain Bike Skills Clinic with Catharine Pendrel

It was another amazing day in Southern California, with the sun shining and a cool breeze blowing. What a great day to be on a bike!


Team LUNA Chix San Diego and Team LUNA Chix LA Cycle teamed up together for the first time to put together a pre-season skills clinic at the Southridge Race Series in Fontana CA. We were fortunate enough to have reigning UCI XC World Champion Catharine Pendrel from the LUNA Pro team in town. By way of reference, here's Catharine with her winning move at the World Championship Race in Champery, Switzerland.

Catharine Pendrel at the UCI World Championships

Girls came from all over SoCal, bringing their enthusiasm and eagerness to learn. Since Dorothy Wong from Team LUNA Chix LA Cycle was on-hand to take pictures, I'll let the pictures tell the story of the day.

Girls gathered outside the LUNA tent.

Track-standing drills in the grass.

Catharine talks about the next drill - lofting your front wheel.

Alexandria practices lofting her front wheel.

Julie, looking pretty solid on this drill.

We all headed up the hill to start the on-course portion of the clinic. 

For a quick look at the day, here's a short video:

Super D Race

On the hill waiting, for the race start

Looking out over Fontana below.

Getting outside to play!

Catharine with junior racers Maddie and Kenzie.

Award  time!!

Catharine and Leti

Leti won the award for Most Improved Rider! (tassels for the bike!)

Angela and Catharine

Angela won the award for Most Aggressive Rider (a horn for her handlebars!). (Angela did the brutal course that ran down the Cal State Downhill course on a hardtail!!)

While we waited for results to be posted, we enjoyed post-clinic/race grilled chicken, sweet potatoes, and garden salad thanks to Steve Drexler (my husband and major race sponsor) and my mom Patricia, who also provided childcare. You two are my heroes.

Liz Carrington won second place in the pro women's class, and Nancy Harris took 4th! Congrats ladies!!

Our clinic attendees all did well and enjoyed the race! From left: Willi Zuckerman, Laura Drexler, Mandy Oliekan, Alex Fabbro, and Julie Bertramd 

The gang!

Liz selects her raffle prize - girly-T courtesy of Ahnu Footwear.

We had amazing support from CamelBak, Genuine Innovations, and Ahnu Footwear, all sponsors of the LUNA women's pro team.. When I pitched the idea to Camelbak of a women's skills clinic with Catharine Pendrel, they were excited for us and offered to supply not only SWAG (everyone got a Camelbak Podium waterbottle), but also items for a raffle in the form of six CamelBak hydration packs! Wow! 

SWAG for everyone!

Jane was very excited about the raffle items from Camelbak!

No less spectacular was the show of support from Genuine Innovations and Ahnu footwear, with Genuine Innovations supplying every attendee with a pink Microflate CO2 head and cartridge, and enough cartridges for everyone to practice using CO2, and Ahnu providing six girly-Ts and socks for the raffle. Everyone came away with great memories, new skills, something to work on and look forward to, and great tokens of the day.

 After I worked with Kenzie on using the CO2, I had her teach her sister. 

Kenzie teaches Maddie how to use CO2.

Steve holds Jane after a long day of sun and bike fun.
You'd think she was in the group hiking their bikes up the hill...

Thanks to all the people who made this clinic happen. We raised $625 for the Breast Cancer Fund and had a great time!
Thank you:
Catharine Pendrel of the LUNA Women's Pro Team
Dorothy Wong from Team LUNA Chix LA Cycle
Cingy O'Grady from Team LUNA Chix San Diego Cycle

Nancy Harris

Sophia and LaVonne at LUNABar 

Kevin at CamelBak

Michael at Genuine Innovations

Elizabeth at Ahnu Footwear

Donnie Jackson at Southridgeusa.com

Steve Drexler and Trisha Gilliland. 

Great job everyone!