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I have an idea to build a carbon fork with aluminium joints. I don't have any experience in frame building but I want to read about it somewhere. Is there any good literature about how to build a bike from scratch?

I've found a couple of books on Amazon, like "Construction of Lugged Bicycle Forks". I think this is the book that I'm looking for. I have a good machinist guy with two turning and one miling big industrial machines.

What I need is to buy two awesome pieces of TAPPERED carbon tubes and then mill a head and dropouts to fit the carbon tubes.

I have some experience with Solidworks and I think I can make a model with all the loads which head should take. I can test all the loads of the carbon tubes and then calculate the head and drop-outs. What do you think, guys?

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    Yes. But without some idea of what research you've already done, how much experience you have with composite design and construction, what machinery you have available, and so on, no-one can answer this for you. What have you done so far? – Móż Mar 27 '16 at 21:37
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    Carbon is a hard material to work with if you don't have an industrial lab/manufacturing setup (most non-bulk frame builders use steel; a few use aluminum or titanium). And a fork is probably the hardest part of a bike to design, so I'm not sure you should start there. – Batman Mar 27 '16 at 23:54
  • Just buy one you like. Seriously. Vote to close as off topic. – Criggie Mar 28 '16 at 5:49
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    So, you can afford the materials and tools, but $15 book is too expensive and you need help getting a pirated copy? – ojs Mar 28 '16 at 9:41
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    I'm not asking for pritate copy here. I'm asking for books and advices you can give. Then I'll buy this book if its worth it. I want to count everything before (materials and labour) before pay for anything. Why so aggressive guys? – alexey polusov Mar 28 '16 at 9:49
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There are some decent websites where people talk about building composite bikes, and even a couple of answers here. But those are mostly either very simple complete bikes, or aimed at people who know a reasonable amount about framebuilding. The book you found is about steel forks, and has only one chapter that seems relevant to what you're doing, and that chapter is marked "optional" in the ToC.

That design stage is critical though. Bicycles are surprisingly hard to analyse using modelling tools, and the front fork is far from the easiest part of the bike to work on. It's also a part where failures are very likely to result in injury. Those two factors mean that it's not a great part to start experimenting on, especially "start toying with framebuilding".

These days with cheap sensors and high-rate portable data collection units it's not impossible to get at least an approximation of the major forces on a diamond frame bike (because you only need 30 or so channels - 8-10 tubes for the frame, maybe four for the fork, with tension and torque for each), but you're only getting an approximation. I don't know of public data like this, unfortunately.

Your design is also relatively unusual as far as carbon forks go, it's more an MTB fork with carbon blades. That doesn't mean it can't work, just that no-one else makes one and there may be a reason why (bast case it might be unprofitable, worst case it has bad failure modes). If you're just going to combine OTS tubes with machined lugs it should be simple enough to build one and see, though. That will also avoid most of the mess and complexity of working with composites, and that's good.

In your position I would be very tempted to make another part first and test that to destruction. That way you get to run through the process and get an idea of your abilities and limits, and you get a part to test. Seatstays, for example. When they fail you tend to end up sitting on the ground, rather than using your face as a digging implement. If you threw together an inverted 4 frame with single bar seat/chain stays you'd have a part similar to a front fork, but with safer failure modes.

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  • Seatpost is a good starting point. However, it's very complicated to mill the top of the seatpost. Should it be forged at first? – alexey polusov Mar 29 '16 at 8:13
  • @FixedGear at this stage you've shown such poor English that I'm reluctant to write any more for fear of you misunderstanding me further. Do you have any friends who are native English speakers that you can get to help you? – Móż Mar 29 '16 at 21:28
  • I thought that I'm good in speaking. However, I didn't understand the last sentence. – alexey polusov Mar 30 '16 at 6:35

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