Bicycle Engineering
Bicycle Engineering
(OP)
I am working with a client that has asked me to design a bicycle component. It looks as if there will be additional bicycle component work coming from them. I am the sole engineer on this, and I have no professional bicycle specific expertise. I'm struggling with determining the appropriate loads / overloads / cycles to design to. I did some searching online and came up with a list of standards that can be boiled down to the list in the Wikipedia article, http://e n.wikipedi a.org/wiki /Outline_o f_bicycles #Standards and more specifically to these few standards / specifications:
EN 14764 City and trekking bicycles - Safety requirements and test methods
EN 14765 Bicycles for young children - Safety requirements and test methods
EN 14766 Mountain-bicycles - Safety requirements and test methods
EN 14781 Racing bicycles - Safety requirements and test methods
EN 14872 Bicycles - Accessories for bicycles - Luggage carriers
EN 15496 Cycles - Requirements and test methods for cycle locks
Each of these specs costs hundreds of dollars, and I can't find any preview as to what I'd be getting. Are these useful for my situation? Are there better sources of information?
Thanks,
Mark
EN 14764 City and trekking bicycles - Safety requirements and test methods
EN 14765 Bicycles for young children - Safety requirements and test methods
EN 14766 Mountain-bicycles - Safety requirements and test methods
EN 14781 Racing bicycles - Safety requirements and test methods
EN 14872 Bicycles - Accessories for bicycles - Luggage carriers
EN 15496 Cycles - Requirements and test methods for cycle locks
Each of these specs costs hundreds of dollars, and I can't find any preview as to what I'd be getting. Are these useful for my situation? Are there better sources of information?
Thanks,
Mark





RE: Bicycle Engineering
How could we know? You haven't told us what "component" you are designing.
Bicycles have been around a lot longer than EN standards.
RE: Bicycle Engineering
Mark
RE: Bicycle Engineering
Section 4.14 for tests that apply to saddle and seat pillar.
No?
Ted
RE: Bicycle Engineering
One of the comments I found in reading the spec and related links was this -
""These EN standards for bicycles have been criticized by many in the industry as inadequate. The main reason for the criticism is that fatigue tests do not apply to fully assembled bikes while the standards for sub-assemblies and components specify only very basic and minimal requirements."
Does that mean that there are tougher standards or references out there that some people / companies work to?
Thanks,
Mark
RE: Bicycle Engineering
Ted
RE: Bicycle Engineering
The company expecting you to design this thing should have given you some criteria to meet I would imagine? If they list a spec to test to, go buy the spec. If they have given you no guidance whatsoever, then go buy a few of these components and break them.
From experience, the highest force on a Seat post collar is when someone gets a few feet of air and then lands. That was actually one off the tests I saw done. They used a Loading dock and just had a guy jump off with a bunch of sensors on him and the bike.
RE: Bicycle Engineering
You can view EN 14765 and 14766 using the following links:
w
w
You are not going to find better information within the public domain than what is contained in the EN standards. In my opinion, if your customer wanted you to design something that could meet a more stringent standard developed internally by a bicycle manufacturer, etc., then they should have provided that up front.
RE: Bicycle Engineering
RE: Bicycle Engineering
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RE: Bicycle Engineering
Perhaps the company that produces the bicycle has some functionality range? I'm sure that a mountain bike would be required to withstand much larger dynamic loads than a racing bike. I'd start by getting some design requirements from the company to determine how harsh of an environment they would like their bicycle to survive. If their requirements are incomplete, you could propose some design requirements to them based on standards or plain old engineering judgment (i.e. what seems like reasonable use, harsh use, etc.).
I'd imagine that many bicycles out there don't conform to all industry standards (though surely many do). You may ask the company if they use industry standards in their designs, and if so, which?
At the end of the day, it's all about clearly understanding customer's expectations.
//signed//
Christopher K. Hubley
Mechanical Engineer
Sunpower Incorporated
Athens, Ohio
--
http://engineeringliberty.wordpress.com