why can't anyone make a fully enclosed 10-speed bike chain/gears?

Discussion in 'Boat Design' started by Squidly-Diddly, Mar 30, 2016.

  1. Squidly-Diddly
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    Squidly-Diddly Senior Member

    OK, this isn't technically a 'boat design' topic, but consider the main drawback of storing a bike on a boat is that nasty, greasy chain and gears.

    Plus this is a forum where people make custom shapes out of a variety of thin and strong materials.

    When I say "10 speed" I mean any bike with both front and rear de-railers.

    You see fully enclosed single speed covers (even if the rear is actually 3 or 7 speed hub).

    Doesn't seem like it would be too impossible to enclose a normal dual derailleur bike gears on a typical road or mountain bike, or even a folder....

    and still be able to pedal without noticing the enclosure.

    The way I see it, the deraileur stuff moves but the range of motion always stays well clear of your feet, and rest of the bike.

    It wouldn't be even close to "wind tight" since there would be pretty big gaps around the rear sprocket where the sprocket set meets the spokes.

    Most enclosure designs are top and bottom clam-shell, which would be my first attempt as well.

    Should be able to remove easily and without tools for the occasional actual "deraileur" where the chain falls off and needs you to get your hands dirty putting it back on. This mostly happens when manhandling a bike in or out of storage place.

    I think my first move will be stiff wire frames on my old road bike, then thick tin foil or plastic wrap over that, just to sort out the shape.
     
  2. Skyak
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    Skyak Senior Member

    I can design it. There is a local company here that is big in 3D printing AND vacuum forming that could produce an effective part at a very reasonable cost with a very reasonable break-even and gross profit.

    So to answer your question "Why can't anyone make a fully enclosed 10-speed bike chain/gears?" I say it's because nobody has ever paid me to do it!

    $30/hr for product engineering plus 20% of gross profit.
     
  3. PAR
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    PAR Yacht Designer/Builder

    The obvious answer is weight and maintenance. If inclosed, some, regardless of significance unnecessary weight is along for the ride. What happens if the chain pops off, now you have to disassemble the guards before you can do anything. Lastly, this guard thing would be prone to trapping things if it had any type of ventilation, so you'd be inclined to design it tight, maybe with an oil bath, further increasing disassemble complexity, maintenance, etc.

    These sort of things usually boil down to some sort of cost/value equation. How much value can you push on this feature, what does this do to the production costs, materials, etc., are we (as a company) required to do this, is there a marketable aero/efficiency advantage that can justify the price point increase, etc., etc., etc.

    I'm sure you could make a simple cover. Wrap the whole shooting match with some foam tape, enough to offer room for things to swing around. Cover with plastic sheeting and CSM/polyester resin. A simple interlocking flange maybe. It'll keep your pant legs out of the chain.
     
  4. philSweet
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    philSweet Senior Member

    There have been several, though they tend to be pricey. The way to do this is not with conventional deraileur systems, but with sealed hub gears and crank gears connected by shafting. Or connected by a fixed chain if you prefer. Electric bikes are leading the way here. But most boaters aren't going to pay more for their bike than for their boat.

    http://ecruiserbikes.com/our-bikes/shaft-drive/
    http://glendalecycles.com/bike-technology/chainless-shaft-drive-bicycles/
    http://www.alexmeade.com/photos/styled-7/index.html(check out the tube coupler system)
    http://www.treehugger.com/bikes/chainless-shaft-drive-bicycle-transmissions-by-sussex.html

    no grease

    http://www.gatescarbondrive.com/
    http://www.bikewagon.com/fallbrook-...2SCSWofp9IixdhQInaf45RIwkZJn0M7BUQaAlqS8P8HAQ
     
  5. Rumars
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    Rumars Senior Member

  6. rwatson
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    rwatson Senior Member

    Attached Files:

  7. Squidly-Diddly
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    Squidly-Diddly Senior Member


    Basically this (3rd drawing showing clam-shell easy-access) but a bit bigger in just the right spots to enclose a Deraileur system.http://www.google.com/patents/US5312303

    There a huge existing number of Deraileur bikes and the chain system has several advantages over shafts so its not going away soon.

    Something made of this stuff, with a few rubber lined hose clamps and a few metal strips for reinforcement and clipping.https://jet.com/product/detail/9ae7...Ke_dSMyKgW29c8O7C6HWt3skZRuN6ucpX6hoC8U7w_wcB I'm thinking well under 3 lbs total added weight for a after market system that could be easily removed and left at home if "racing for money".

    Doesn't need to be tight or with any oil bath. Bikes now use this for chains.http://www.whitelightningco.com/products/lubricants/easy-lube
    Goes on wet to penetrate, then dries to wax which self sheds when it gets dirty. IIRC it also become liquid when actually under mechanical pressure at contact points and sort of self-refines. Trick it to remove all factory grease first otherwise it wont adhere properly. Why bikes still ship with old style grease I can't explain.

    You don't need anything more that a wind resistant fit, just enough to stop wheel flung dirt and water (because road-water is dirty water) from hitting the drive-train. You don't really even need to prevent nice clean rain water while stopped.

    You also want to prevent other stuff from direct contact with drive, particularly the chain, even with White Lightening. Just something so that luggage etc can be placed up against the bike without fear of nasty grease stains on everything.

    More of a Chain Fender than a Chain Enclosure.

    The wires and tape would be just to double check the dimensions.

    Besides the "woman's market" for people that just don't like getting anywhere near greasy machines in daily life, there should be a big market for off-pavement riders who like riding in mud, but don't like spending time cleaning their bikes afterward, and its impossible to clean a derailleur well without taking the whole thing apart with special tools.

    Except for extreme jumping and other stunts, de-railments are pretty rare in RIDING unless the bike is way out of adjustment or the chain is extremely worn out. IMO they mostly happen when manhandling the bike in or out of some awkward storage (like back of a car) and something contacts the drive-train.
     
  8. Skyak
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    Skyak Senior Member


    IMHO
    -off road bikers don't want any more bike surface area because it just adds to the weight of mud accumulated. They plan to get dirty when they go out.

    -performance road bikers are quite sensitive to weight and wind drag -not an easy sell but may be willing to pay up for performance.

    -commuters will buy in droves. They are so sick of %$@# grease on their cloths, snagging on the chain and having a grease pit on their otherwise glamorous bikes they will pity the fool that does not have the guard. Most commuters are urban and carry their bikes through doorways daily -another opportunity to get dirty grease where it doesn't belong. This is a small fraction of the bike market, but it is still huge in numbers.

    -that white chain grease is great, but it still turns to black grease over time with dirt and metal wear and it still stains anything it touches.

    That plastic pan you referenced is thermoformed, Polyethylene PE most likely. It should be OK against grease exposure, but it will be thick, heavy, and prone to rubbing on the chain or gears -too clunky and undesirable.

    You are WAY off on your mounting.
     
  9. Rurudyne
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    Rurudyne Senior Member

    Replace the chain with a link belt and the gears with either pulley equivalents or a continuously variable transmission set up (as is used on a Shop Smith, for example).

    That would eliminate most all grease.
     
  10. Squidly-Diddly
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    Squidly-Diddly Senior Member

    Mountain Bikers don't mind getting themselves and clothes filthy, because you are just gonna shower and throw it in the washing machine anyways.

    But they feel pain when their high end components get covered in mud and there is no good, much less easy, why to clean them.

    Yeah, I'd probably make the outside Teflon coated, or maybe just recommend Teflon spray to help mud fall off. But I'd still much rather brush or scrape a layer of mud off a flat-ish plastic cover after a muddy section of trial with a handy branch than off all my deraileurs.

    Those plastic pans are pretty light weight, IMO and they stand up to mixing concrete with heavy steel shovels and hoes. I don't need anything stronger than heavy duty Saran-Wrap stretched tight, just needs to hold its shape.

    What do you mean "way off on the mounting"?

    I don't think I've even begun to figure that out but I guess it would be from several points on the frame with little rubber lined hose clamps and some lightweight metal struts. Probably "bend to fit". Mostly it would be Huffy patent I linked, just stretched over a more voluminous drive train. I figure a big (if low end) bike company sorted out the mounting.

    I agree the Commuter would be the best market. IMO lots of people WOULD use bikes on Commutes if not for the chain issue. Most buses and trains now allow bikes which makes them much more useable. My second biggest prob using mass transit is not being able to find a bathroom or appropriate corner to piss in within walking distance.
     
  11. Rumars
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    Rumars Senior Member

    Mountain bikers wash their bikes with a pressure washer at the DIY manual car wash. Afterwards they oil the chain. That is why they encapsulated bearings are for.
    A real commuter bike is SS or has a 3, 7 or 14 gear speedhub with fully enclosed chainguard. Ladys bikes have skirt guards as a standard. They also often have front drum brakes for use in wet weather.
    Low end or hybrid commuter bikes come with "normal" chainguards (non enclosed) even if fitted with derrallieurs.
    That is the normal state of things in europe.
     
  12. Squidly-Diddly
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    Squidly-Diddly Senior Member

    Yeah, I've seem them at the car wash. I guess that is for those that live in Apartments ("Flats") and don't have an outside hose at home.

    Still seems less than ideal. The two little cogs on rear deraileurs still often have fully exposed bearings, which look plastic and maybe are supposed to run dry?. A bike shop mechanic once told me a common problem is dirt on the deraileur cable ends, but only at the deraileur end, not at the handlebars, for obvious reasons. Mud gets into the cable housings from the cable going in and out when dirty, then it starts rusting and eroding the cable and housing causing rough shifting.

    Haven't tried one since my old Raleigh Made In England 3spd, but I've been told the gear hub bikes give up a lot of performance compared to derailleurs, so only good for short, flat commutes.

    I was stuck on a hard plastic or even sheet metal cover but after remembering this....http://inhabitat.com/transportation-tuesday-bmw-gina-light-visionary-model-revealed/

    I'm now considering flexible titanium wire frame (like those eyeglass frames) and stretchy fabric. Even a very porous fabric would be able to defect wheel flung dirt and water.

    A fabric cover could even be machine washable.

    If I was going to get real tricky I'd hang the rear frame off the rear derailleur small cog gear frame so the fabric cover wouldn't need to be so wide and would follow the chain as it moved back and forth. But that would require some real engineering to prevent the stretch fabric from fighting the derailleur movements.
     
  13. Skyak
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    Skyak Senior Member

    Squid,
    Take it as as just an opinion, but mountain bikers that actually ride off road would not strap that thing to their bike if you paid them anything less than what a new bike costs. Why do you think the guard will hold mud and dirt out but not in? MTBers would presume the opposite. Mounting is critical because the derailleurs are very sensitive.

    I have limited time in Europe but would confirm what you say. Commuters are a big percentage of bikes in Europe and a big percentage compared to car owners. They are less sensitive to price and inefficiency so the hubs are a fine choice.

    In the US commuting tends to be farther and faster for lack of public transport and theft is still a big problem -so derailleurs rule with a lot of 'fixies'. It is rare for any bike commute or errand to not involve sharing the road with 25mph+ car traffic. If you tried to sell a popular European commuter bike in the US the response would be "for that price and weight I can buy an electric assist".
     
  14. bpw
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    bpw Senior Member

    Mountain biker here,

    Don't think any of us would enclose the drive train, extra weight, would trap dirt and you need to get in there every couple rides for maintenance and an added step would be a hassle. Much easier to give it a quick hose off and oil the moving bits if everything is exposed.

    It would get destroyed on the first ride in most areas from bouncing over rocks and logs unless it could support full body weight, and then it would weigh a ton.

    I have owned motorcycles with covered chains, pain in the neck to remove and didn't help keep things clean when riding dirt just more difficult to clean.

    I really think gearhubs with belt drives or a minimal chain cover are the answer to this problem.
     

  15. Squidly-Diddly
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    Squidly-Diddly Senior Member

    Someone will call it a "derailleur diaper".:p:eek:

    When I was a kid I'd take the fenders off my new bike because it was cooler and more 'tough'. Now I'm shopping for expensive full cover fenders. "Crud" brand. Might also stretch fabric completely across the rear frame triangle.

    I seem to be getting a pretty solid push and shove from my derailleurs. I can hold my thumb very firmly against them and still overpower with the shifters, which is why I'm thinking stretch fabric is doable. It would only be about 7degs defection from the front, so not much torque on rear mounting.

    I think something like that BMW car could be considered fashionable, at least among the Silicon Valley performance road rider groups in Los Altos, Woodside etc. They all wear various gaudy corp logos all over their bike shirts and shorts. Some hi-tech stretch fabric would be just another place to put corp logos.
     
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