Bicycle dropout design.

[adajio]

Hi everyone,

I'm currently a design engineering student and my final year project involves redesigning the fork-ends/brackets/dropouts.​

However, I am having some trouble sourcing specifications and finding information on their manufacture and material composition.​

Do any of you know where I could find this information (or any suppliers I could contact)?

Thanks in advance...

 

[Milkfloat]

I don't know enough to help. Although I am intrigued to know what problem you are trying to solve?

I do know on the steel front, some are cast and some are pressed and some are laser cut.

Surly know a few things about bikes, here is some information from them http://surlybikes.com/blog/post/i_know_a_lot_of_dropouts

 

[Yellow Saddle]

I am intrigued to know what problem you are trying to solve?

That question is so important that your professor should give you full marks if you return nothing else but just that question. I did that to one of my students once.

There is an EN specification for bicycle manufacturing (@raleighnut may know about this.) I don't know if it is relevant to the specifics of drop-outs though.

Engineering and design students are FOREVER attempting to redesign the bicycle. We see this every single year at project and assignment time. Every year. Did I mention each year? The designs are always a mess and always laughable. Always.
There is a reason why design changes in the cycling industry are slow. That is because a bicycle is a mature technology that only requires tweaking as legislation, conditions and available materials change.
It will pay you to first study the history of the Rover safety bike (and before) to understand why things are what they are.

Only with that in mind can you offer a re-design.The rationale is much much more important that some fancy radical re-design with purple anodising.

 

[S-Express]

I'm currently a design engineering student and my final year project involves redesigning the fork-ends/brackets/dropouts.

It would be useful to understand what the perceived issue is that you are trying to address with the redesign?

 

[TheDoctor]

Of all the bits that need re-designing on a bike (which is not that many, frankly) the drop-outs would be last on my list.
As has been said about this (and probably every other) attempt at improving upon a mature design, what problem are you trying to solve?

 

[Yellow Saddle]

Of all the bits that need re-designing on a bike (which is not that many, frankly) the drop-outs would be last on my list.
As has been said about this (and probably every other) attempt at improving upon a mature design, what problem are you trying to solve?

Without giving the OP too many clues and doing his homework for him/her, the drop-out has required a re-design with the advent of disc brakes. The laywer's lip was just an inconvenient stop-gap until something better came along and it recently did - the TA.

 

[Dogtrousers]

It's certainly a fascinating subject, and I (and others here) would probably be interested to see what your conclusions are.

The functions of the dropout are multiple, and they are related to the use that the bike is put to and the material from which the frame and the dropout itself is made. Does it need to mount a sacrificial hanger? What is its role in chain tensioning? What is the braking system in use? How will the wheel be secured? What mounting eyelets does it have? Dropouts crop up in all kinds of discussions. I recall reading, for instance, that Rohloff have very exacting dropout requirements. The world of dropouts on racing frames will be a whole other specialism, as will mountain biking and so on. Then you'll have considerations related to mass production ... The more I think about it, the more interesting a subject it is ... and the less I know about it.

Good luck with the project.

 

[Pale Rider]

It's certainly a fascinating subject, and I (and others here) would probably be interested to see what your conclusions are.

The functions of the dropout are multiple, and they are related to the use that the bike is put to and the material from which the frame and the dropout itself is made. Does it need to mount a sacrificial hanger? What is its role in chain tensioning? What is the braking system in use? How will the wheel be secured? What mounting eyelets does it have? Dropouts crop up in all kinds of discussions. I recall reading, for instance, that Rohloff have very exacting dropout requirements. The world of dropouts on racing frames will be a whole other specialism, as will mountain biking and so on. Then you'll have considerations related to mass production ... The more I think about it, the more interesting a subject it is ... and the less I know about it.

Good luck with the project.

I agree, although the OP appears to me to be looking at front - fork - dropouts.

A redesign may not be needed, but it's good to think outside the box even if the conclusion is the best design is the one already in use.

 

[rualexander]

You might find the Ceeway website and it's dropouts pages worth a look: http://www.framebuilding.com/

http://www.framebuilding.com/NEWPARTSPAGES/Forged Dropouts.htm

http://www.framebuilding.com/NEWPARTSPAGES/Cast Dropouts.htm

 

[Dogtrousers]

I agree, although the OP appears to me to be looking at front - fork - dropouts.

A redesign may not be needed, but it's good to think outside the box even if the conclusion is the best design is the one already in use.

Bugger, didn't read the OP properly.

I agree with your thinking. My big dissertation at uni concluded "I couldn't find anything interesting, although I looked really hard using various techniques". I got good marks for it. Possibly the only thing that scraped me through my degree.

 

[mickle]

Here's one wot I rote seven years ago. Nothing has changed.

http://www.cyclorama.net/blog/ramblings/designer-bikes/