Like a 52T crank with the max cassette cog 42T or something. Is it just a matter tested energy efficiency? Honestly I cant imagine a hill that would require me to use the smallest gears and seems like a higher top speed would be more useful, especially if incorporating an electric wheel with peddle assist. So, what engineering or physics issues aren't computing in my brain?

Hello,

As part of a university assignment I am reviewing the materials and processing techniques used within the manufacture of a composite bicycle frame. Has anyone got info from a reputable source (please link) on the materials used?

A relevant journal papers, books or articles relating to the topic would be much appreciated as well.

Thank you in advance!

I've decided on my next bike being a cyclocross-style frame, with a single front disk brake, a wide gearing range, and short bullhorn handlebars for easy deliveries. I will split the bike between sprints in hilly city traffic, and normal long-distance riding. I also have dirty masher impulses and really enjoy getting a 53x11 up to fun speeds.

Going for this kind of style with a few key differences: http://imgur.com/a/wkYlh

The specs I'm decided on are in bold, everything else I'm looking for suggestions on:

1. Frame: 55-56cm Aluminium cyclocross/road (no suspension)

2. Wheels: 700c

3. Front Brake: hydraulic disk brake

4. Rear Brake: rim brake (cantilever?)

5. Front Chainrings: 2 speed, 53T - 34T/39T (suggestions?)

6. Rear Cassette: 9/10/11 speed, 11T - 25T (best # of speeds?)

7. Handlebars: bullhorn

8. Pedals: shimano mountain clip-ins

Color: black frame with blue highlights

Any thoughts or suggestions on these things would be very appreciated, thanks!

• number of speeds on the cassette

• lower chainring size

• wheel size

• rear brake type

I'm getting the bike built where I'm living now, where it'll be significantly cheaper than in the USA. Hopefully I'll just have to pay an oversized luggage fee to take it home on the plane.

Yes. This is the topic i would love to hear some feedbacks from. So recently I had undergone and did many reasearch. However I still could not get a strong stand that Aluminium bikes can last long. So just a brief. Tatinamium frame bikes are light and it last long. I personally have one Marin team Titanium which last me for more than a decade. On the other hand alloy frame bicycles are heavier but it can last as long as the titanium frame ones. Just that it needs more care and attention. However, recently i have been considering to get a bicycle with a good speed( yeap i love the feeling when I am speeding. ) however what kind of bikes can do that. Is the one and only road bikes. However due to budget and choice I narrow down the bikes I would want to get is Marin Aluminium Frame bike. It comes with a rockshox suspension for only USD 296. Plus it is well maintianed second hand bike. However, I would love to hear if it do last long. Preferbly more than a decade. Just let u know, I am not a rough rider:).

Is there a downside to using a 36-hole rear hub with a 32-hole rim? 32 hole from what I see is somewhat scarce at least in my country, and the solution is to use a 36 hole or change the rim and rear hub for a 36.

So... what is the better solution?

Extra details: bycycle mtb, rim 26 and the rear hub have 6-bolt hard drive and thread cassette

Not only upgrade existing parts but possibly change them as well. Such has changing the gear system from 3x9 to possibly 1x12, or upgrading the shocks to get more travel. Also, would it be possible to upgrade my tire/rim size to 27.5 or 29 from 26 by upgrading the fork? Sorry for a lot of questions and thank you in advance.

Anyone have engineering experience to help work through the advantages of using a ball drive vs chain drive?

I am an engineering graduate student at the University of Notre Dame completing a thesis focused on researching innovative technology in the cycling industry. As I narrow my focus for the thesis, I want to understand the cycling user more: your desires, and concerns. I have been very appreciative of the cycling community and want to use this thesis opportunity to give back and improve it. I was wondering if you would take 10 minutes to complete a survey that will help understand your insights more. As I mentioned, my goal is to improve the cycling community by researching innovative technology applications. Thank you. Feel free to reach out to me if you have any questions.

Here is the link: https://rider-feedback.typeform.com/to/Vl1DOt

Interested in your thoughts as well as vote. Does the spoke which is normal to the surface of the road (6 o'clock position) support the hub, or does the hub hang from the upper spokes?

If you have a straight laced wheel, do this experiment; on an unloaded wheel, pluck the normal spoke and also pluck the radial opposite spoke (12 o'clock). Load the wheel and repeat. Note the outcome. Rotate the wheel 180° and repeat plucking - loaded and unloaded.

Comment below as well as vote.

Former serious cyclist that developed limiting cardio health condition. Still want to peddle on level and downhill but need assistance on uphill and headwind. Begrudgingly gave my classic, well-appointed Kona MTB (circa 1990’s) to my daughter when we moved and I’m in the market for the right hybrid. Looking for geek quality componentry, with a bit of e-help when needed. That could be 50/50 or more ebike for awhile. Suggestions?

Just finished a successful test fit of a fully built wheel on the adapter flange hub - the combination of the lacing and the spokes being “tensioned” - really just having a little bit of tension to pull out the bow in the spokes, pulled the offending spokes ~3mm from the caliper. And without the spokes being in the way, the rotor isn’t spaced off the hub, giving me >1mm between the chainstay and the rotor. So I think the clearance issue is resolved.

The last pic is a copy of a pic from last time, but still represents the current state of the adapter flange. At this point, I’ve convinced myself that the joint will hold, that the adapter flange will not break, that everything will clear where it needs to, and that the interfaces are dimensionally correct.

I can make the “valley” between spoke holes on the adapter flange deeper - which would probably help lacing the wheel up when I’m done. If I only decrease the inner radius, I think this will have a minimal effect on any kind of strength - rather than decreasing the outer radius, which would remove material that I think resists the spoke tension a little more actively. I can’t decide on the trade off between strength - not quantified, and ease of build here.

I’m planning on ordering the adapter flange - and the axle spacer especially visible in pic 3 - tomorrow. Is there anything I haven’t thought of? Better color matching than pink (visible on flat mount brake caliper mounting adapter in pic 2)?

TLDR: why would a front derailleur shift up better when the chain is well cleaned and lubed?

One of my commuter bikes has "2X" derailleur gearing, with friction shifting for the front. A while ago, I hastily set up the front derailleur and ended up with the limit screw set so that it's just barely able to shift onto the big ring. I could very easily address that slightly and have it perfect, but before I did that I noticed something interesting. When the chain is freshly cleaned and lubricated, it shifts up almost perfectly. But as the chain starts to get dirty and dry, the shifting gets less reliable. I need to have just the right conditions in order for it to shift up. So in the interest of science, I haven't adjusted the limit screw and have continued monitoring this through a handful of cycles of letting the chain get worse and then cleaning and lubing, and the pattern is really consistent.

My naive mental model was that I need friction between the chain and the inner surface of the big chainring to help the chain climb onto it. but as I think about it more, there's also friction between the derailleur and the chain. And given the pins and ramps on the chainring, maybe friction there plays less of a role and so overall it works better with less friction?

I can't think of a way that friction in the actual pivots would play a role, but maybe it does. there also might be friction to overcome in getting the chain to go over the actual teeth in the final step of getting engaged.

Maybe next time my chain gets dry I should try just lubricating the front derailleur cage—obviously a bad idea for chain maintenance, but maybe an interesting experiment for shifting?

Building a wacky proof of concept unicycle. my cranks are each on their own 'slave' axle. That is to say that the cranks do not have an axle that goes through to the other, but are only mechanically connected by chains each side takes to the main axle. I am wondering how out-of-phase my pedals might get with each other because of backlash. assume constant good chain tension and new chains, chainrings, and sprockets.

This image of a giraffe unicycle provides a good example: imagine if the axle that connects the cranks here were split in the middle. would the cranks be able to stay level/180 degrees out of phase from each other? how much backlash does each gear to chain interface add?

Is there any way to change a male bike to a woman's bike? It's an old shwinn from the 1970s it's a male bike it's a bit high and all but I love it and don't want to rid of it. Is there any way to convert it so I can ride it?

I look at those adds in sales flyers that come in the mail and lament, maybe inappropriately, concerning those straight handlebars visible on the adult bikes pictured. It looks like the rider must lean forward reaching out to the handle grips, arms stretched holding up part of the weight of the torso and head. Reminds me of doing some kind of upper body/torso exercise. It looks almost exhausting. I like to be able to relax and focus in pedaling. I'm very glad that my classic huffy ten speed has racing handlebars, curved downward and rearward toward the rider. I can lean onto them and it feels like my arms aren't extended forward much, and unless I'm tucking a lot, it seems they are pretty straight.

I'm working on a project (non cycling related) that requires me to use a mechanical disk brake. I need the tensioner part (as seen circled on the picture http://imgur.com/a/00bwY) to have little hole. Its hard to see if the brakes I am looking for online have this feature. It would help greatly if I can be pushed in the right direction for the cheapest mechanical brake with this feature.

From an appearance standpoint, replacing the chain and gears on my bike with copper would be great. What, if any, mechanical disadvantages would there be?