1. In their book Lean Thinking : Banish Waste & Create Wealth In Your Corporation, authors James P. Womack and Daniel Jones provide a 3-4 page case study on traditional bicycle production and then write on how lean thinking can be applied to make value flow in better ways. It starts off with historic ways of order-taking, design and production and tie together some new techniques to create a lean bicycle production process. You can read most of it here electronically on a Google Books preview.
2. It has been only a few months since Cycleops released their new "Pro" line of bicycle trainers, and there's already a voluntary recall on all of them, as of last week. The problem child on the design seems to be their yellow skewer clamp or lock ring that comes out loose while in operation. Read below :
A better look :
So while you may train indoors like a total badass, you may also go flying out and over your setup due to the vibrational forces involved in hard efforts.
3. If you like digging into old Time Magazine articles, here's one from way back in 1971 on an apparent bicycle shortage in the U.S! Demand was super high, but retailers & bike companies were unable to keep up. I wonder if we can learn anything from history...
4. Weightweenies had a post on a Campagnolo Bora rear wheel damage :
How it happened, from the rider : "I had to brake hard for a crash in front of me and I also had to steer. Because of that my tube came loose from my rim and I hit the asphalt on my rim instead of on my tube. On the photo's you can see that the sides of the rimbed are damaged. The damage that you see on the photo's is the only damage to the rim. There are no visible cracks or whatsoever. Also the rim is still completly true."
More pictures with interesting comments here.
Its terrible that we keep seeing more of these incidents, particularly when the price of replacement may be a steep cry. Now I had written two similar posts on this issue sometime back so I give them to you for further reading :
1.Tubulur Tires Exploding And Peeling Off
2. Rim Heating During Hard Breaking
5. Most of you may have easily missed this news, so I bring it to you again. At Eurobike 2008 in Friedrichshafen Germany, there was a Taiwanese bicycle manufacturer called Asia Seiko who presented a really lightweight frame, using some interesting frame materials. The buzzwords for the combo makeup is TeXtreme® spread tow fabrics and TeXero® UD tape, developed by a Swedish company called Oxeon. The tape weaving process is patented technology which was discovered back in 1995 by Dr. Nandan Khokar at Chalmers University of Technology in Sweden. You can read more about this frame here, and about Oxeon's patented taping process here.
If anyone has any more interesting updates about the frame, let me know.
Asia Seiko's one piece Fight Weapon frame, made with 80gsm (areal weight) TeXtreme carbon fabric, claiming to reduce the overall weight and increase stiffness.6. A Competition In The Works : Last but certainly not the least, I've been thinking about running a small competition on this blog. I haven't done so yet, so this will mean I'll have to plan something with a small, yet a nice prize for the winner. I have some ideas going in my head to make it a little wild and unique, and it may come online anytime now so keep your eyes open and keep checking the blog.
But here's your chillout tune till then. Ciao!
Posts
Why does that Asian frame look like a replica of Look.
ReplyDeleteI think that while there may be issues with tubular tires and their relationship with mating surfaces on rims, I think this incident shows not a problem with carbon wheels, but rather how strong this one was. It shows that while part of the rim was literally ground off, the rest remained intact, and did not fracture or explode. I find this to be a comforting fact.
ReplyDeletefocal's right. What is the crying about? I know it was an expensive rim and all bit just think what used to happen to rims back in the time when they rolled off a rim.
ReplyDeleteGive us a break, a glued on tire can only take so much before it comes off and now with the stiffer rims a whole lot less tires come off than there used to be... with a whole lot better results afterwards carnage wise.
-B
There may be the thinking in people's minds that glued-on tires are somehow invincible. Sudden braking forces on the rim together with the twist on the tire while turning can could unseat a tire, so there's not much hope in trying to explain the way it happened, but take a lesson home that glue and rubber unfortunately have their shortcomings so base your riding style around that. Meanwhile, what could this rider have done to avoid it? Should he really have run right into the person in front of him without steering? Could he have braked any harder as he rode straight ahead? Somethings to think about...
ReplyDeleteRon, those questions cannot be answered well since there are things we don't know yet. For example, what was the velocity he had. How close was the rider in front of him before he applied the brakes. 100m? 70? 30? I guess you could then come up with a rough figure for braking stop distance assuming he applied the brakes the moment he saw the crash.
ReplyDeleteThis begs a question I had for sometime, are disc brakes better at braking power than rim setups?
ReplyDeleteYes, disc brakes offer much more stopping power. However, there are other issues with disc brakes, but keep in mind that increasing stopping power only serves to stop the wheel from spinning, which can create a skid quite easily with a skinny road tire.
ReplyDeleteHaving a lot of expierance with tubulars from my days as a team mechanic I would like to point out that the likely root cause of this issue was that the rim was not correctly prepped and the tubular was not properly installed.
ReplyDeleteIf you look at the pictures, the rim surface is too smooth, and was not prepped with glue. It also appears that the tublar was also not prepped and did not recieve enough glue either.
I am pretty confident the cause had nothing to do with braking, or the rim heating up, or any other design related issued and was simply basic human error.
- Ryan
Crap, sorry about the miss spelled words.
ReplyDeleteI foolishly replied before my first cup of coffee.
Hahaha.
- Ryan
Ryan,
ReplyDeleteThere may not be any glue in the pictures because the user removed it all for photo purposes. He even claims that his LBS did the original glue job. That is pretty ridiculous if professionals cant get it right.
The fact is, I still believe this type of accident has something to do with the glueing, and the nature of the physics behind the sudden braking (that locks the wheel) together with the sideways motion of the tire will lead to the tubular rolling out. Its pretty intuitive to just visualize. Remember this happened to Beloki once? Check those two additional links in red out.
The element of comfort seems to be the fact that its occurence is not common, but it can happen. Tubulars, in my opinion, is ancient technology, and a well performing tubular takes for granted the fact that the tubular itself is of high quality, the gluing is done by a very experienced professional and the tire will not unseat in the event of sudden hard braking together with shear forces due to sideways motion of the tire against the road.
For those who're curious whether the carbon rim can be repaired, the answer is yes. Carbonology offers repair kits for composite bicycle frames and rims. However, I do not feel the rim will be structurally in an optimal position as per original design condition to handle cornering. Maybe be sad, but for the extra cost of replacing the rim with another one, you may be saving your health and life.
ReplyDeleteGreat info Ron... enjoyed reading the "bicycle shortage" article from Time. I'll be passing along the CylceOps recall info to a friend who just recently made that purchase. Looking forward to hearing about the competition.
ReplyDeleteDon : I'm interested in knowing whether your friend with the trainer experienced any problems himself during use.
ReplyDeleteRon – Regarding your physics reference, you forgot to to include the factor of the lap shear strength of the glue to your model.
ReplyDeleteAncient technology does not equate to bad, or poor technology. If it has been in use for this amount of time, it usually means quite the opposite in fact.
Every tire has the potential for failure failure with respect to the rim.
Just because it happened to Beloki doesn't make it likely for every tubular wheel.
Step back and look at the frequency of this kind of failure combined with the quantity of product in the field. While your points are relevant, and could cause a problem with a similar outcome, I would say to you again that the likely cause of this is human error.
Look at the picture again.
Notice that the rim is as smooth as a babies bottom?
This is a clear indication this rim was never prepped for proper installation as it should be very rough.
Also, if the rim was properly prepped, it would also have a significant layer of glue as a primer base which is very difficult to remove.
Lastly, if the tire was properly prepped, it would be coated with a significant amount of glue also.
Do you know how difficult it is to remove all this glue?
It is an extreme pain in the ass on the rim, and basically impossible on the tire.
We all know that not all bike shops do have the same level of professional service, and even inside a single shop the service can be a rather broad spectrum, but I feel it is unfair to blame a rather significantly proven design just because it is highly likely the installation was done poorly.
- Ryan
Ryan,
ReplyDeleteAll good points. I may not have much experience with tubulars as you do. However, I guess my point was that hard braking (assuming rim brakes and alloy braking surfaces are used) may cause the glue itself to heat up and weaken, thus compromising shear resistance. Some of the tubular glue I have seen are heat sensitive and there's are warnings on the back of the container signaling this. I wonder then if there's a high temperature quality glue out there that can make a difference. Whats your experience?
Ron - You need more then of an expert then me on this.
ReplyDeleteI have practical knowledge of things I learned in the field and they do work, but I do not have any pure science to back up my experiences.
Colin S. "Chip" Howat is the man you want to talk to.
Here is a link on what he has already published on this topic.
http://www.engr.ku.edu/~kuktl/index.html
On the left side of the page click on Bicycle Research.
There you will see a 9 part study on Tubular Tire Adhesive Performance.
Please note: I learned that the surface of the carbon rim has little to no affect on the adhesion of the tire! If you only knew how many hours I wasted on just that, you would be amazed.
Oh and regarding the crash of Beloki, my interpretation of this was he did a classic motorcycle highside.
Highside Dynamics - http://www.msgroup.org/forums/mtt/topic.asp?TOPIC_ID=2192
Motorcycle highside - http://www.youtube.com/watch?v=pI2U3djAZ6Q
As for Rogers, the accusation that the tire rolled came from his brother while watching video footage which doesn't actually show anything because the moto arrived after the crash happened.
His theory was pure speculation.
- http://www.cyclingnews.com/news.php?id=news/2007/jul07/jul16news3
RON-- I don't believe so... I talked with him yesterday and he said his local bike shop was either fixing or sending him a new one.
ReplyDeleteRyan : Great links. I'll have to get deeper into this and get back to you. Motorcycle Highside, wow thats something new to me. I asked a friend who's a lot into motorcycles and even he has no idea what that means.
ReplyDeleteDon : Excellent. Atleast he didn't find it the hard way out.