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Wooden bikes

materiabikes.com

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Re: Wooden bikes

#181

Post by samstave »

abakker wrote: post #124
mr_overalls wrote: post #114

Engineered wood is truly an amazing material. While touring a newly-constructed home a few weeks ago, I saw what appeared to be floor joists constructed out of thin, cheap particle-board. It turns out that they're made of engineered wood, and are actually stronger than an equivalent sawed wood beam. https://imgur.com/a/3AkZblF

Engineered wood and chipboard/ Oriented strand board (OSB) are a very different animal that particleboard or MDF. Each has their purpose. True particleboard is a very crappy material, best used for ballast and being cheap. MDF is smooth, stable, and machinable, and OSB provides a lot of tortional resilience. For any home woodworkers, I don’t recommend working with OSB or particleboard. However, OSB is moderately wate…

In the 80s, in Tahoe, we built a tree-fort near my house. My dad was a general contractor and we had a lot of MDF available to use from his company...

Yeah - MDF and SNOW do not a happy tree house make.

The MDF sops up water like a sponge and deteriorates into its constituent particulate... which really sucked because our fort had two levels....

We built a house on the truckee river and there was a giant glue-lam beam that was used for the main truss of the roof. It had to be custom ordered from some manufacturer, and when I asked my dad why we were using that, he talked about how the glued laminate layers were stronger than a single material beam.

Re: Wooden bikes

#182

Post by samstave »

CompelTechnic wrote: post #119
leni536 wrote: post #29

The best materials for damping vibration have low density and low stiffness. When coupled with the low vibration transfer speed, these properties determine how well a material damps vibration. Based on the table below by "stiffness" they mean Young-modulus. None of these quantities describe damping of vibrations in a material. Also Young-modulus and density determine the longitudinal vibration transfer speed (this is…

Yeah, I've still rarely seen honest discussions about what damping means in terms of structural materials. If you made a bell out of cast iron instead of bronze, it would still ring, but it would ring for a shorter duration. This is because cast iron has higher internal damping than bronze. It is a viscoelastic effect, in that energy lost is proportional to the speed of movement (strain rate) within the material. I i…

Does this have to do with the "grainy" texture of cast iron? I would think that it has more surface-area-like to traverse, thus the vibrational waves attenuate super fast, as opposed to brass where they can carry?

Re: Wooden bikes

#183

Post by hammock »

ramy_d wrote: post #170
Eric_WVGG wrote: post #155

Earlier quoted context omitted.

There's a blogger called “Bike Snob” who has been ridiculing cyclist gullibility and fleeting trends for over ten years. One manufacturer of wooden bicycles decided to just up and send him one, and… well I'll just quote him: > Before getting the bike: Intrigued by the novelty factor and an excuse to make gratuitous wood puns > Shortly after receiving the bike: Impressed by the exquisite craftsmanship but also kind of…

I found a sequence of updates from the guy if anyone is interested: https://bikesnobnyc.blogspot.com/2017/11/bsnyc-field-trip-20... https://bikesnobnyc.blogspot.com/2017/11/would-that-i-could.... https://bikesnobnyc.blogspot.com/2017/11/this-title-is-100-f... https://bikesnobnyc.blogspot.com/2018/06/wood-bike-status-up... https://bikesnobnyc.blogspot.com/2018/01/sawdust-in-wind.htm... read for yourself

This guy is funny!

Re: Wooden bikes

#184

Post by samstave »

sergiosgc wrote: post #14

I don't understand the market for bicycles in the thousands of euro price range. Bikes get stolen often enough for me to never be relaxed leaving such a bike outside a shop or caffe or such. If you can't leave the bike anywhere, it's almost useless, except perhaps as a virtue signalling device.

I have a bike that I term "ride-able art" Its not for racing, and while its not terribly expensive, I love it, care for it and don't want it stolen.

I have had several bikes stolen from me - its such a horrible feeling when that happens.

Re: Wooden bikes

#185

Post by eitally »

gameswithgo wrote: post #148
eitally wrote: post #109

Earlier quoted context omitted.

But dampening happens differently in different parts of the frame. For example, thinner & curved seat stays vs a suspension fork, or round 853 steel tubing vs highly aero-optimized low profile carbon, or deep dish carbon wheels vs traditional aluminum. Your statement is technically accurate, but that doesn't mean the feel of the ride will be equivalent.

Professional level riders are absolutely certain they can feel the difference between deep carbon wheels vs aluminum when they test them. Then if you disguise the wheels such that they cannot tell which is which, they are completely unable to discern them. The same is true with frame types typically believed to be vastly different. A professional triathlete and ex cat 1 road racer I know was sure he could tell the di…

Perhaps I unreasonable assumed we were comparing a Cervelo (any) to a wood frame, not two high-tech carbon Cervelos (fwiw, I ride an S3). There absolutely are differences and the gamut is broad, but the differences are subtle when comparing two very similar products.

As an aside, the placebo effect is real, and I attribute a lot of strong product opinions re: fitness equipment (doesn't matter if bikes or running shoes) to how they make people feel, not how they objectively perform.

Re: Wooden bikes

#186

Post by samstave »

blakblakarak wrote: post #23
tcgv wrote: post #17

I wonder if wooden bikes bring any safety concerns in the event of a crash, since when wood breaks it can become reasonably sharp, like a spear.

I doubt the risk is any worse than with carbon fiber. http://www.bustedcarbon.com/

https://www.youtube.com/watch?v=rTfu0hjVtzE

Carbon bike disintegrates at 107 MPH

Re: Wooden bikes

#187

Post by bigpicture »

cultus wrote: post #129
ubermonkey wrote: post #110

Earlier quoted context omitted.

Are you certain about this? Because I'm not sure it's true based on my own relatively recent experience test-riding a variety of fairly serious road-cycling frames.

I can't find the source at the moment, but there was actually a test done where riders rode bikes of carbon vs. alloy or steel with the frame material obscured from view. They couldn't tell the difference. When everyone is telling you that carbon has a better ride quality, it's hard not to feel it. Steel is the best frame material for 95% of people due to its durability. Quality steel frames (not Schwinn travellers)…

> Steel is the best frame material for 95% of people due to its durability. Quality steel frames (not Schwinn travellers) are quite light.

I have a bike made with True Temper OX Platinum steel and it is my favorite bike by far. It is a very light frame, but that is not what I like about it. Steel (and titanium) frames can be made with tubing of a much smaller diameter than that of aluminum or carbon. I believe that the tube diameter (and associated stiffness) is what people are feeling when they talk about the difference between bikes.

If you make a steel bike with tubing that is indistinguishable from aluminum or carbon, I am not surprised that nobody can tell the difference!

Re: Wooden bikes

#189

Post by braindongle »

gameswithgo wrote: post #82

The vibration dampening is a red herring. As a point of comparison, the differences in dampening between various frames/materials is on the order of ~1psi of tire pressure normally. In other words, if you found yourself with the harshest of frames, you could drop air pressure by 1 or 2psi and be at the same level as the "smoothest" frame.

Woo-woo! Engineering word police, open up! "We dampen sponges. We damp vibrations."

Re: Wooden bikes

#190

Post by ema »

cultus wrote: post #137
toxik wrote: post #131

Earlier quoted context omitted.

While true that tire stiffness is a major player in vibration transfer, it also trades off friction. As we all know, stiffer tires (higher pressure) is faster. I think you're reducing a complicated mechanical system to a few variables; mountain bikes, for example, have dedicated shock absorbers. Granted, they're for much harder impacts, but something similar could be said of high-frequency shocks.

Too high pressure actually decreases efficiency. While you have less deformation of the rubber, it causes the bike to bounce over irregularities more. The energy from this bouncing is lost. On rougher roads, often pressures below 90 PSI are best.

As a casual cyclist 50 psi already feels like "this is amazing I just hope my tires aren't gonna burst". So it seems "higher is better" is solid advice for most people, who aren't gonna go over 90 psi anyway.
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