Cassette How-To - Part 2

http://www.slowtwitch.com/Tech/Cassette_How-To_-_Part_2_3257.html

This is the second (and final) segment of our How-To on cassettes. If you missed it, part one is located HERE.

The first segment of this article was dedicated to the standard procedure of removal, cleaning, and re-installation of a cassette. The same basic steps are used for all modern multi-speed cassettes, whether they’re 9-speed, 10-speed, 11-speed, SRAM, Shimano, Campagnolo, or whatever. Unless you’ve got something really odd, it will work in the way we described.

This article is dedicated to the very complex topic of cassette spacers. Specifically, we’re talking about spacers that are located behind the cassette.

 

SLIDESHOW

In the photo above, I have a Shimano 9/10 freehub with a SRAM 10 cassette – no spacer necessary. Should YOU use one? Why or why not? In order to discuss that, we must also delve in to the history of freehub standards, and explain how it all evolved. 


Spacers and Freehub Standards

The first thing to understand is the fact that there are different freehub shapes out there in the market. A freehub is the part of your rear hub that the cassette mounts to. Other names include ‘cassette body’ and ‘freehub body’. 

By far – the most common shape of freehub is known as ‘Shimano 9/10’. More than likely, this is what your wheel has. Before 10-speed existed, it was simply called a ‘Shimano 9’ freehub. They’re characterized by a set of short splines, with a single wide spline for properly locating the correct cog orientation. As an example, here is a Shimano 9/10 freehub from a CycleOps Powertap SL+ (made by Joytech):

 

In contrast, here is a Campagnolo-specific freehub, for a Zipp 182 rear hub. Notice the different shape (deeper) splines:

 

Great – cool. So where does the spacer talk come in? Spacers really entered the scene in a big way with the advent of 10-speed Shimano components. They decided to squish an extra gear in to that cassette, and fit it on to the same freehub. To do this, the cogs got narrower, along with the space between each cog. The strange thing was, however, that the total cassette width actually shrank to be 1mm skinnier than the 9-speed version. So – more cogs, AND less total width. In order to fit on to the same 9-speed freehub, they began supplying all 10-speed cassettes with a 1mm ’10-speed spacer’. They look like this:

 

Easy enough, right? Sure is. Well… until it got complicated. First, some back-story:


Begin backstory:

The 9-speed freehub was intended to be made out of two materials: steel or titanium. Steel is heavier and cheaper; titanium is lighter and more expensive. Both materials are sturdy enough to do the job. What happened, though, was that other manufacturers (besides Shimano) started making 9/10-speed freehubs out of an even lighter material – aluminum. Yes, it is really light – but it is also soft. What happens over time as a result? The cassette cogs actually dig in to the freehub splines. Your forward pedaling action smashes the cogs in to the freehub, and they start to dig little notches in to the aluminum. 

 

The smallest two or three cogs are wider, and don’t notch nearly as bad. The biggest cogs are usually stuck together via a single alloy carrier, which is wide and does not dig in to the freehub. It’s the middle cogs that are the problem. They’re narrow – only the width of the cog engages to the freehub.

These notches present a problem when trying to remove your cassette; the middle cogs get jammed in to place, and you can’t pull them off. The easiest solution is this – take a shop rag, place it over the cassette, and try to force the stuck cogs counterclockwise – out of their notches. If that doesn’t work (i.e. your freehub is really bad), there is a two-person method. Person 1 holds the cassette with a rag. Person 2 carefully takes a flat head screwdriver, and places it against a tooth of the stuck cog. Then they gently tap the handle of the screwdriver with a hammer.

 

This screwdriver-and-hammer method has never failed me. If the freehub is badly damaged, the only solution is to replace it with a new one. Keep in mind that this is usually not considered to be a warranty item by most wheel manufacturers. The aluminum freehubs are doing exactly the job they’re supposed to – be a light racing product. As we know, the definition of a racing product is something that gives up longevity and durability for light weight and/or speed. If you keep killing alloy freehubs (and don’t like buying new ones), consider going with a titanium or steel model next time around. Or, train on a training-specific wheel/hub (with a steel freehub), and then race on a racing-specific wheel. 

End backstory.


Shimano saw this aluminum freehub business going on, and decided to do something about it. They knew that they couldn’t make an aluminum freehub in the existing 9-speed shape – at least one that would last more than one season. So, they did what they always do… re-engineer the design. What they came up with was a new spline shape. Take the old 9-speed model, and make the splines substantially longer. Longer splines mean more contact between cassette-and-freehub… so no more digging and notching. While they were at it, they also made the freehub 1mm shorter, so the little spacer would no longer be necessary. 

Behold – the Shimano 10-speed ONLY freehub (shown with a 1mm spacer to prove that it won’t fit on the deeper splines):

 

For comparison, here is an image of the older short-spline 9/10 freehub (left), and the newer deep-spline 10-only (right):

 

This new freehub was a fantastic solution to the problem. However, it created a new one - it was a new standard. The 9-speed freehub was around for years, and the industry was comfortable with it. It works with 9 and 10-speed cassettes, so it is versatile. A few manufacturers got on board and started selling the 10-only. But most were slow to react, and stuck with the 9/10. Besides, the older-style meant quicker freehub failure, and more sales of new freehubs… why change?

Alas, after a few short years, Shimano themselves dropped the 10-only freehub. They reverted back to the 9/10, and using titanium freehubs as their lightest option. Today, you still see a very small handful of wheel manufacturers selling the 10-only, such as Easton. If you only own Shimano 10 cassettes, they work great (i.e. you don’t own any 9 or 11-speed, and nothing from any other brand – SRAM, Sampson, etc). If, however, your drivetrains are diverse, you’re better off sticking with the 9/10. 


Going to eleven, Mavic, and more

Many of you have heard that the new 2013 Dura Ace 9000 is going to 11-speed. You may have also heard that it requires yet another – newer – freehub. The splines are the same short style as the 9/10 freehub, but the total length of the freehub is longer by 1.85mm (to accommodate the additional cog). This means that if you have an old wheel with a 9/10 freehub, you cannot use it with an 11-speed cassette. You must buy a new wheel that is 11-speed. However, the 11-speed wheels are retro-fittable for 9 and 10-speed. They come with a 1.85mm spacer to take up the extra slack. If you have a 9-speed cassette, you only use the 1.85mm spacer. If you have a Shimano 10 cassette, you use the 1.85 PLUS the 1mm 10-speed spacer.

In a stroke of either luck or genius, Mavic wheels are already 11-speed compatible. Their wheels always included a 1.75mm Mavic spacer, because their freehub is extra long (by 1.75mm). This photo compares their spacer (right) with the Shimano 1mm spacer (left). 

 

If you want to use 11-speed Shimano components with a Mavic wheel, simply use no spacers at all.



Charting it out

This is all really simple, right? I hear you – it’s not simple at all. In fact, I’m guessing that if you’ve read this far, your eyes are glazed over, and you might even be drooling a little. This is definitely an area of the bicycle that has become unnecessarily complicated. I personally understand how it works, but I’m a rare breed of nerd. For those of you for whom this type of stuff is not second nature, I put together a table that will hopefully clear things up. 

The table covers most potential situations and setups of cassettes, but is by no means all-inclusive. I chose to include products and standards from Shimano, Campagnolo, SRAM, Mavic, and Sampson, as they are – in my view – the most common in the US, and also what I’m most familiar with. There are a handful of other cassettes out there – Miche, Wheels Manufacturing, and IRD – to name a few. If you happen to have one of these cassettes, my advice is to follow the manufacturer’s instructions, or call them with questions. Also, this entire topic will continue to evolve, as manufacturers jump on the 11-speed bandwagon… and inevitably move to 12-speed, or whatever comes next. 

 

Update:

Some of our readers brought up the fact that their Mavic wheels required a special .55mm spacer to use with Campagnolo 11-speed. I inquired with Zack Vestal from Mavic for further detail; here is his response:

“The reason that some Campy 11 users need spacers is that the very first ½ production cycle [of wheels] in the early days was run before they realized the new cassettes - in some sizes - didn’t fully clear the hub flange. This was on a few wheels only. [For those wheels], a small ‘band-aid’ spacer was required. I think this may have even been limited to just a certain few R-Sys and Ksyrium wheels with taller, more blocky hub flanges. That’s why it’s just .55mm of spacer – just enough to push out the cassette a tiny bit. 

In later versions, no spacer is required.”

--

All images © Greg Kopecky / slowtwitch.com

Looking For a Bicycle Repair Course

Looking for a Bicycle Repair Course – Bike Teacher Has What You Need
Are you looking for a bicycle repair course? Do you want to repair bicycles professionally, or are you just interested in taking care of your own bike? Regardless of your reasons, if you want a great bicycle repair course, then Bike Teacher has just what you need.

Bike Teacher Offers a One‑On‑One Personal Experience

We keep class sizes low so that you can get one‑on‑one time with your instructor. You will learn by doing. This is called experiential learning, and it’s proven to be very effective. We are completely hands on and will make sure that you get the training you need in our bicycle repair course.

Bike Teacher’s Bicycle Repair Course Can Be Done on Your Schedule

Yes, that’s true. We have various times available for you to take our bicycle repair courses. Whether you want to do a special project on your bike or need help learning the basics of bike repair, we’ve got a bicycle repair course for you. Our variety sets us apart from our competitors, but so too does our willingness to work with you. We know that your time is valuable and you may not have the time to take your bicycle repair course during the day. Nearly everybody’s got to work. We have Monday through Friday classes available anytime between 8am – 10pm and weekend classes are optional and totally doable. We will schedule your bicycle repair class on your time. Bike Teacher is happy to work out class times that best compliment your life. Just contact us for more information.

What Kinds of Basic Bicycle Repair Courses Does Bike Teacher Offer?

We have a beginner, intermediate and advanced class. In our beginning class, little to no prior skill is required. We will help you learn to maintain and repair the most common bicycle issues. For four hours, you will learn flat tire repair, how to adjust the brakes, brake pad replacement, derailleur replacement and a chain replacement. Our intermediate class, which is also four hours, further explores bicycle repair. In this bicycle repair course, you’ll get into the nitty‑gritty of bike repair. You’ll learn some of the more complicated issues that you could come across while caring for your bike at home, issues like: brake cable replacement, derailleur cable replacement and adjustment, chain life evaluation, pedal removal, headset adjustment and introduction to bearing diagnosis. Our advanced bicycle repair course lasts 12 hours and will help you become a well‑rounded bicycle mechanic. You’ll learn the most challenging aspects of bike repair including wheel truing. You can divide up the hours however you need to. All classes welcome beginners to experienced bike mechanics.

What other Bicycle Repair Courses Does Bike Teacher Have?

We have a tune‑up course that teaches you how to tune‑up your own bike. It’s pretty intensive and we have various options that you can take. See our website for more information. We also offer a 40‑hour and a 70‑hour class for people who are interested in making bicycle repair their career. We cover so many topics in both classes that you’ll be able to handle any challenge that comes your way. Our bicycle repair courses will provide you with certificates of completion so you can go out into the world and make bicycle repair a rewarding career.

All of our offerings are located at http://www.biketeacher.com/classes/. Check out our bicycle repair courses. We’re sure you can find something to fit your needs.

I've been seriously riding for over 20 years. (Bike Teacher Review)

I've been seriously riding for over 20 years. I own an assortment of bikes, including hybrids with grip shifters, road bikes with Shimano index shifters, a tandem with a monster disk brake, and a high-end carbon-fiber bike with electronic shifters.  For years, I've worked on this assortment of bikes with trepidation, as I knew enough to be dangerous.  As a birthday present, my wife signed me up for the 40-hour class from Arthur.  

As others have noted, Arthur is a very patient teacher. When he says "let's remove that widget", he intends that you should remove it.  This is not a class where you watch the teacher.  You are wrenching on your bike (or his) while he's nearby giving advice if needed.  When you've dropped his tool or a handful of bolts and washers on the floor for the nth time, he calmly retrieves them. When you are about to install something backwards, he gently points out the issue.   When you work one-on-one, you have the opportunity to ask all of the questions you always wanted to ask. Even stupid questions are respectfully answered.  Arthur's shop is fully stocked with top-of-the-line Park tools, and he knows how to use all of them.  

In this class we serviced hubs and bottom brackets, replaced brake and shifter cables, removed and reinstalled cassettes and chain rings, measured chain stretch, removed chain links and replaced chains, straightened bent derailleurs, trued wheels, replaced spokes, adjusted brakes, and serviced head sets.  Not only am I confident that I can diagnose what's not working on my bikes, I now am confident that I can probably fix it.

Last, Arthur taught me how to think like a mechanic.  When we encountered problems that weren't simple to fix, he taught me how to carefully and methodically approach each problem. Tricks and tips were revealed, and sage advice was olled out constantly.  If you really want to learn about bike maintenance from a great teacher, then I highly recommend his 40-hour class.

Best Bike Repair Classes in California

Bike Teacher is known for having the best bike repair classes in California. We give you personalized instruction and we work on your schedule. Bike Teacher’s classes are what you need to succeed with your own bicycle repair and in the bicycle repair industry. We leave nothing out. You’ll learn everything you need to know to maintain and repair bicycles and have fun doing it with Bike Teacher.  Now, we’ll let you know what the best bike repair classes in Southern California can do for you.
 
We offer beginning, intermediate and advanced bicycle repair classes that will teach you about all the systems of a bike and how to maintain and repair each component. In the beginner class, you’ll learn how to maintain and repair the most common issues associated with riding a bike such as flat tire repair, brake adjustment and chain lubrication among other things. Our intermediate bike repair classes will show you how to do a brake cable replacement, a chain life evaluation and replacement, and tackle pedal removal. Our San Jose area bike repair classes will teach you how to set up bicycle shocks to handle specific rider weight. Not many of our competitors do that. In our advanced bike repair class, you will learn wheel truing and hub overhaul among other things. Our bike repair classes are comprehensive at every stage of learning. Bike Teacher truly offers the best bike repair classes in Southern California.

If you live in the San Jose area and want to become a professional bike mechanic, we have bike repair classes that will help you accomplish that goal. We have a 40 hour class and a 70 hour bike repair class which includes certification upon completion that will teach you how to work in the bicycle industry and keep bikes working at optimum levels. You get one on one instruction and are able to work on your own bike, or one of ours. Bike classes include everything from tubeless tire set up to rider position set‑up. Our bike repair 40 hour class can help you work on being the best bicycle mechanic you can be. Of course, our 70 hour class covers more information and will help you learn about the different style of components that you’ll run into on a day to day basis in a bike shop once you become a professional bicycle mechanic.
 
If you don’t want to become a full time bicycle mechanic, that’s fine. Bike Teacher has special project classes. In these bike repair classes, you get to choose what you work on. You’ll get one on one instruction and complete working on your bike at a very affordable price. You can take the classes on an as needed basis and on your schedule; learn on your own terms how to fix your own bike.
 
Bike Teacher also offers Southern California bike repair classes for businesses and special events. We do pro bike builds for those of you who are interested in that, we provide shock service, and we offer bike repair classes on suspensions, bearing replacements, and tubeless tires. Contact us today for the best bike repair classes in San Jose and the surrounding areas. Our phone number is (408) 210‑2890. We’ll be happy to accommodate you.

Bicycle Mechanic School

Benefits of Bike Teacher’s Bicycle Mechanic School
When you enroll in a bicycle mechanic school, you obviously want to see benefits. Bike Teacher’s bicycle mechanic school has some obvious benefits for aspiring bicycle mechanics. In this article, we’ll go over 5 such benefits. We hope you enjoy them and they encourage you to join us.

1)    Flexibility of classes. Bike Teacher lets you set the class schedule that’s right for you. We understand your time is precious and we work hard to offer classes that meet at a time that works for you. Monday through Friday classes can start as early as 9 am and go as late as10 pm. We work around your schedule. Saturdays and Sundays are also options. Just tell us what you need and we’ll do our best to accommodate your schedule. If you know what your schedule is like ahead of time, you can lock in your bicycle mechanic school hours early and know that you’re covered. However, if your schedule changes a lot, then you can set up classes as you go. We don’t penalize you either way, and you won’t get this kind of flexibility at any other bicycle mechanical school that we know of.

2)    Small class size. At Bike Teacher, we keep classes small so that there’s a good student to teacher ratio. Many of our students work one on one with their instructors. We find that smaller class sizes give each student a better opportunity to learn the material hands‑on. They also give our instructors the ability to give their students personalized attention. It’s one great thing that sets our bicycle mechanic school apart from others out there.

3)    Payment plans for specialties 40 hours and over. Our bicycle mechanic school is not very expensive, but we understand that many people have to live within a budget. For those of you taking advantages of programs that have 40 or more hours, we offer payment plans. Like our class schedules, they are flexible and encouraged to work within your needs. We really want you to enjoy your overall experience with us and want to make it one that is affordable too. We understand your needs and try to exceed expectations. We accept a flexible array of payments including cash, PayPal, Visa, MasterCard, American Express and Discover.

4)    Learn on your own bike while fixing it. C’mon, you love your bike. We know it. If bicycles are a passion of yours and they have to be for you to consider bicycle mechanic school, then you have a bicycle. You get the opportunity to learn on your very own bicycle, so you’ll know it like the back of your hand. That gives you extra confidence and capabilities. You can say you practice what you preach and that you work on your very own bike. You can trust yourself and us with bicycle mechanic training.

5)    World‑Class Curriculum. Bike Teacher uses the Park Tool Big Blue Book of Bicycle Repair for its classes. We teach to the book. It’s an industry standard. Our bicycle mechanic school turns out well‑educated and informed bicycle mechanics. You can have faith in the curriculum we use. You are getting the best information possible.

We really hope you can see the benefits to enrolling in Bike Teacher’s bicycle mechanic school. We are totally committed to helping you have a wonderful educational experience whether you are a bicycle hobbyist who wants to repair his or her own bike or desire to work on bicycles in a bike shop for a living. Contact us today at either via email at arthur@biketeacher.com or by phone at (408) 210‑2980.

Bicycle Mechanic Training

Bike Teacher Has Bike Mechanic Training Classes Available Now

It’s 2016! That means it’s time to get your bike mechanic training at Bike Teacher. Classes are forming now. We offer convenient schedules. We have openings seven days a week, including evenings. You can choose when you come in for your class. We are flexible and open to having you receive your bike mechanic training.
 
Bike Teacher has bike mechanic training classes for the novice all the way to highly advanced bike mechanics, and everywhere in between. We even offer bike mechanic training certifications. We follow the Park Tool Big Blue Book of bicycle repair for our bike mechanic training classes. Our classes are hands‑on. When you take the 40‑hour and 70‑hour classes, at your convenience and customizable for your skill set, you receive a certificate. The 70 hour class covers every aspect of bike repair that you can imagine. Bike shops look to us for referrals for bike mechanics. You can receive your bike mechanic training through us and you can ask to be put on the list and stay informed about jobs in the bicycle repair industry.

Working with Bike Teacher to learn more about bike mechanic training is rewarding and affordable. You can take predesigned classes or custom make your own classes. We really work hard to work with you. You can bring your own tools or your own bike or work with ours. We provide materials for you. If you choose to buy materials through us with any class you take, you will get a shop discount.

We use Park Tool tools. They are the best bike tools on the market and preferred for bike mechanic training. Bike mechanics prefer them for home and professional use. Park Tool has a dedication to quality, innovation, and customer service.
 
Bike Teacher provides you with a hands‑on experience with our special bike mechanic training. We provide bike mechanic training for beginners, bike shops, enthusiasts, race teams, bike clubs, businesses, and recreationists. You’re guaranteed to find bike mechanic training that will work for you regardless of your experience level at Bike Teacher.

Give us a call today to set up your class. We can’t wait to work with you on your bike mechanic training.

Alum Rock Park Bike Ride

My steering felt funny as soon as we left the parking lot. Gorgeous Day most would consider this a boring park to ride but the scenery was spectacular.

 It felt as if I had extremely low air pressure or my front tire was very sticky to the ground. When we arrived at the park I felt the headset was loose, tightening did nothing so I took a peek inside and found the bearings had come off the designated bearing cage. This could have been the beginning of the end of the ride for me, luckily the bearings popped back into place and a way we went. The stem never sat flush, there was obviously something wrong with the headset.

 For whatever reason the headset came loose, probably from use, either way the looseness and continued riding produced the bearings to fall out of place and gum up the feel of the steering. Putting the bearings back into place and readjusting the headset did the job; despite the gap in the headset it felt great. Oh well, sometimes stock parts break down like this after a year so I was not surprised.

 Bikes, hikers, runners and horses can be found here. As far as bike riding goes prepare your self for many feet of climbing with little to no technical trails involved. You come here if you enjoy a change of scenery from plush redwood shaded canopy riding and a challenging workout. I like it in late winter to spring; everything is green and bright this time of year. I often cycle from my house in Willow Glen to Alum Rock as a destination turner around point.

 It often reminds me of Riding in Monterey, near Laguna Seca Raceway. Except with less opportunity for single track. The ground is usually hard packed unless there have been consecutive days of raining. Then it's off limits, it becomes too sticky and you and your bike won't stand a chance. If you looking for more challenge technical terrain with more single track, jumps and drops, visit Soquel Demonstration Forest in the Santa Cruz Mountains.

 At Bike Teacher we provide complete hands on bicycle mechanics repair and maintenance training for beginners, enthusiast, bike shops, race teams, bicycle clubs, businesses and recreationalist.
 Located in the North Bay, San Jose California.

Limit Screws, Rear Derailleur

The "B" Screw, an often forgotten about adjustment and rightfully so. Hopefully this screw goes unnoticed to those who struggle with the rear derailleur adjustments. There’s a good chance this screw will not yield the fix your looking for. The only time this screw is turned is when the derailleur is first installed and even then some bikes have no reaction to it from what I’ve seen. So don't sweat this guy too much. If there is a problem you should notice it in a particular gear, the biggest gear in the rear (cassette) and most likely the smallest chain ring in the front. This selection will allow the chain to relax quite a bit producing a problem IF it exists, not always.

The problem is this, a noise that is produced when upper pulley wheel of the rear derailleur is so close to the biggest gear on the cassette, it begins to rub. The pulley wheel has the chain riding on it, which, together, makes contact with gear, producing a rolling vibrating sound. Simply* turn the "B" screw clockwise (righty tighty) enough to allow some space between the two. Textbook calls for 4-5mm of space. *In some cases the screw is hard to turn so you will have to unweight the derailleur body along with the "B" screw off of the hanger, taking the pressure of the screw, allowing you to *easily turn the screw.

Here's where videos, pictures and text don't do you justice.biekteacher.com

Bicycle Mechanic Training and Cerification

Bike Teacher Has Bike Mechanic Training Classes Available Now

It’s 2016! That means it’s time to get your bike mechanic training at Bike Teacher. Classes are forming now. We offer convenient schedules. We have openings seven days a week, including evenings. You can choose when you come in for your class. We are flexible and open to having you receive your bike mechanic training.
 
Bike Teacher has bike mechanic training classes for the novice all the way to highly advanced bike mechanics, and everywhere in between. We even offer bike mechanic training certifications. We follow the Park Tool Big Blue Book of bicycle repair for our bike mechanic training classes. Our classes are hands‑on. When you take the 40‑hour and 70‑hour classes, at your convenience and customizable for your skill set, you receive a certificate. The 70 hour class covers every aspect of bike repair that you can imagine. Bike shops look to us for referrals for bike mechanics. You can receive your bike mechanic training through us and you can ask to be put on the list and stay informed about jobs in the bicycle repair industry.

Working with Bike Teacher to learn more about bike mechanic training is rewarding and affordable. You can take predesigned classes or custom make your own classes. We really work hard to work with you. You can bring your own tools or your own bike or work with ours. We provide materials for you. If you choose to buy materials through us with any class you take, you will get a shop discount.

We use Park Tool tools. They are the best bike tools on the market and preferred for bike mechanic training. Bike mechanics prefer them for home and professional use. Park Tool has a dedication to quality, innovation, and customer service.
 
Bike Teacher provides you with a hands‑on experience with our special bike mechanic training. We provide bike mechanic training for beginners, bike shops, enthusiasts, race teams, bike clubs, businesses, and recreationists. You’re guaranteed to find bike mechanic training that will work for you regardless of your experience level at Bike Teacher.

Give us a call today to set up your class. We can’t wait to work with you on your bike mechanic training.

Skeggs Mountain Bike Ride

Skeggs Mountain Bike Ride

We rode Skeggs, in Woodside California Sunday January 24th also known as Corte Madera Creek Open Space Preserve. This is a great place to mountain bike if you you like your single track with fire roads and a healthy dose of climbing. It's universally canopy shaded so it offers some relief in the summer time. You can make short loops or just about any time frame you want in this park. There is nothing too technical here. The area's that are in question will make you a better rider with challenges you can opted out of. I like what this place has to offer, fitness wise. Just be sure to go prepared with plenty of food and water and a specially good map reading skills or a guide.

This accident happened about 2 1/2 miles in on our way out. The rider Jose tried to jump a downed tree stump when the tire hit the tree half way over in it's cycle when the wheel finally hit, it happened to be in a week spot of the wheel (previous hit) and Bang! the tubeless tire blew and over the bars he flew to a forgiving landing. He is fine but the Crank Brothers wheel got destroyed immediately. 

Bike Crash Destroys Wheel

We rode Skeggs, in Woodside California Sunday January 24th also known as Corte Madera Creek Open Space Preserve. This is a great place to mountain bike if you you like your single track with fire roads and a healthy dose of climbing. It's universally canopy shaded so it offers some relief in the summer time. You can make short loops or just about any time frame you want in this park. There is nothing too technical here. The area's that are in question will make you a better rider with challenges you can opted out of. I like what this place has to offer, fitness wise. Just be sure to go prepared with plenty of food and water and a specially good map reading skills or a guide.

This accident happened about 2 1/2 miles in on our way out. The rider Jose tried to jump a downed tree stump when the tire hit the tree half way over in it's cycle when the wheel finally hit, it happened to be in a week spot of the wheel (previous hit) and Bang! the tubeless tire blew and over the bars he flew to a forgiving landing. He is fine but the Crank Brothers wheel got destroyed immediately. 

At Bike Teacher we provide a complete hands on bicycle mechanics repair and maintenance training for beginners, enthusiast, bike shops, race teams, bicycle clubs, businesses and recreationalist.
 Located in the North Bay, San Jose California.