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No More Greasy Bike Chains?

Posted November 19, 2010 7:00 AM by Sharkles

There is no reinventing the wheel, but it is possible to change the system that powers it. In the bike industry, manufacturers are developing alternatives to traditional lubricated chains used on bicycles today. These chains require regular oiling and attract dirt as a result, opening the bike rider open to greasy clothing.

One idea for replacing messy chains is to move to belt-driven systems that are made of polyurethane and then shot through carbon chords for tensile strength. The belts feature teeth on one-side that interact with metal pulleys to turn the belt as the bike petals rotate.

According to an article in The New York Times, belt-driven bike systems would likely be more expensive than traditional chains and would only be able to be used on bike frames designed specifically for them. However, they write that the low-maintenance and grease-free appeal may make biking more attractive to urban dwellers.

Do you think moving to belt-driven systems would be worth not dealing with greasy bike chains?

Source: The New York Times

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#1

Re: No More Greasy Bike Chains?

11/20/2010 12:06 AM

It has certainly worked for street motorcycles. But wouldn't it pose a mechanically complex and therefore costly way of shifting gears?

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#2
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Re: No More Greasy Bike Chains?

11/20/2010 2:54 AM

It would for derailleur systems, but might be well suited to internal hub units. Although these are less problematic due to the same gear being used all the time, thus not collecting debris on unused rings.

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#4
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Re: No More Greasy Bike Chains?

11/20/2010 1:08 PM

A double sided cog tooth belt could be used same as a chain for shifting.

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#3

Re: No More Greasy Bike Chains?

11/20/2010 11:01 AM

In addition to requiring the purchase of specific frames, there is only the two methods ( for now) of creating drive. The external geared drive and the internal. The use of a belt-drive requires the exclusive use of an internally geared drive in addition to weakening a frame at an already weak location. The stresses and forces applied during riding at the dropouts (rear axle mounting location) are higher due to the reduced tube diameter and thickness. The additional use of a bolt to hold together a frame ( required to install a belt) creates a greater weak point due to the clearances needed to be able to install a bolt, the clearances combine and add impact stresses on the bolt and threads (in addition to the normal forces) which will lead to a catastrophic failure on what are (on average) unmaintained bicycles.....On top of this: your choices for an internally geared drive are limited to commuter bikes or extreme off-road bikes. Sachs and Shimano make 3 speed, 5 speed and 7/8 speed models.... none are able to handle more than 2 years for regular riding and most don't work in temperatures less than 7 degrees Celsius. Their cost ($150-700 for the hub complete (no internal parts are replaceable) is far beyond the cost and ease of chain replacements.... and you have to pay for a wheel build ($70 and up)...... The chain and its' 150 year history of yeoman service is here to stay....

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#5
In reply to #3

Re: No More Greasy Bike Chains?

11/20/2010 2:02 PM

Applying external grease to part is old technology. New which is grease free is providing grease in the steel itself. During my past work interest I created Iron sulphide in the steel which is glassy phase and is very good grease. The control is important based on need. Sulpher also help to make free cutting steel but also decrease strength since iron sulphide is formed mainly at grain boundry At high end parts and system one does not need external lubrication source and can do very good job by embedding in materials which provide lubrication based on need and provides optimum use out of grease

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#6
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Re: No More Greasy Bike Chains?

11/20/2010 5:54 PM

I don't see where you find the need of extra bolts - mounting the belt pulleys instead of gears would not make excessive differences to the current set-up. I agree that the current internal gears are not as robust as they could be - the old 3-speed Sturmey Archer units just went on for ever! But should the current units be properly mass produced & quality engineered, they could easily become close to the cost of derailleur units. My bike also has hub brakes - they do not fade in poor weather and only require occasional greasing. I must have saved £80 a year on pads and even more on rims.

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#7

Re: No More Greasy Bike Chains?

11/20/2010 11:02 PM

Sealed o-ring chains are available that need no external lubrication and could be made out of stainless steel to keep them from rusting.

I don't know why it would be so hard to do a gear/cable drive with a continuously variable speed rear hub.

Or even a small hydraulic drive with variable speed rear hub.

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#8

Re: No More Greasy Bike Chains?

11/22/2010 12:13 AM

It has already been available in Japan for at least 5 years. The attraction was the cleanliness, since so many people here ride bikes to get around, even women in skirts (with special guards around the wheels to keep the skirt from getting caught in the bicycle wheel). The Bridgestone B8 (introduced in 2005) had an 8-speed internal-gear system. Current belt-drive bicycles range from about $300 and up.

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#9

Re: No More Greasy Bike Chains?

11/22/2010 12:46 PM

Dear Sharkles, In a perfect dirt free world, a bicycle belt drive would a consumer option. In the real world, they are a pain in the butt. Yes, you have to unbolt the chainstay, the lower tubes that connect to the bottom bracket/crank area, to replace a worn belt, which becomes a weak point. Yes, the cheap versions are single speed or three/five speed internal hubs, the more expensive models use 8 or more internally geared hubs, which means more small parts to manufacture and more things to go wrong. When you ride in the rain, oil from the road and dirt get on the belt itself. Ride down to the beach for an ice-cream, what do you think sand and air born silt do to the wear and tear? Don't get me wrong, I think belt drives have potential. But there are other problems, the rear cog and front belt ring are not perfect circles from each other. Being non-concentric, the belt is tight in one spot and loose in another. This makes premature wear and tear on everything, including the bearing wear in the rear hub. In the dysfunctional world of no standards in engineering, how many different length belts are we going to have? Sorry sir, that SKU number is discontinued, we stopped making that belt in 2009. In the bicycle world of chains, there are connecting links that work just fine. How about an injected molded stainless band snap link that slides together from the side for easier installation? Expand the technology to farm tractors and tank treads. By the way, nobody should grease their chain, only oil them and wipe off the excess. The belt does have a future.

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#10

Re: No More Greasy Bike Chains?

01/19/2011 10:23 AM

I have always wondered why bicycles were still built to a two hundred year old design when almost every other mode of transport was going to solid wheels, tuned suspensions and internal gear boxes. Surely the two hundred year old design (steam punk! ha!) is not the be all end end all of two wheeled transport? Belt drives work really well with snow mobiles....with automatic shifting no less! There may be a place for it in a the bold new future! They certainly work well with timing mechanisms and snow mobiles!

But at the risk of sounding like a grumpy old phart, this particular post sounds like a solution in need of a problem. Dirty pants legs? Hah, ever heard of a chain guard? Clothes caught in the chain or wheels? Ever heard of fenders? But we got a cute little belt thingy here, with all kinds of high tech carbon filiaments inside that needs hundreds of dollars worth of re-engineering and different gear boxes per unit, and we think it will be perfect for, um...what. Replacing a cheap plastic chain guard. Riiiiiight....

Good luck finding venture capital for THAT one!

(Yusef shakes his head and wonders out loud, "What ever happened to "form follows function"")

But lets go back to my lead paragraph here...the ancient design. Traditionally, tech advancements in vehicle design were driven by competitions...that is to say, by races like Mosport, and the Brickyard, and rally driving! For bicycles, it would be the Tour de France and so forth. This has resulted in bicycle design which by and large, resembles "race winning" designs. Any bicycle which does not resemble a "Tour de France" bike is looked at with amusement. "Unfair" say I. When you have had to share an elevator with a friendly sweaty young couple with their bicycles, you suddenly think, "you know there might be a better way!" Lets see if we can find some, hmmmmm?

Thomas Owen's "One" is a true citizen's bike with a VERY innovative drive train! It also folds up, the dirty parts fit inside and sells for under two hundred bucks.

Then there is the Taurus bike....which eliminates the seat. You know, there are people like me who detest sitting down. Not many, I admit, but lower back pain means I cannot sit astride a conventional bicycle. This one also has a VERY innovative drive train! And no pedals! OMG! NO pedals! Ha, it uses a stair master trick to drive it! Me...I would like to see this one electrified! The Taurus bike has a future! Its a concept though...not a production bike, but guys, lets get away from the tour de france look because, you know, me and my friends will NEVER win a bike race, we don't drive sports cars, and we don't wear spurs on shiny cowboy boots when we go for a beer. We are old guys that frankly don't look so hot in tight bike shorts!

Then there is the inexpensive "Sandwich" bike. Made by Bleijh concept and design, it uses a low tech solution to create a remarkably pretty, yet inexpensive bike. It uses a chain system as well though the chain is enclosed inside the body. Away from pants and skirts. This truly green design has a future.

Cannondale's Jacknife bike uses a hydraulic drive system. This foldable bike has no chain or belt, only hydraulics. A concept bike which in my opinion, needs people on CR4 to look at more closely. A lot of things I didn't like about it, (the frame is IMHO not made up of UCI mandated light weight triangles, but it DOES fold up so you can prop it beside your desk.) A hydraulic system has a lot of advantages. It may be history that will decide if the instantly set perfect gear ratio would be worth the fraction of a percent loss in efficiency, about the same losses as a flex belt. For racers, no. But for commuters more interested in watching out for idiot car drivers than for constantly changing gears, this might be the way to go.

There are always "concept" designs which might need some innovative belt drive systems though. The I bike. (sorta like an ipod you ride I guess.) Its not about the ride, its about the listening experience!!! grin!

So there you see....I am not just a nervous nelly ultra conservative old phart! I just think there are a lot more innovative ideas than replacing a chain with a belt.

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#11

Re: No More Greasy Bike Chains?

10/08/2021 12:15 AM

Is the ease of being able to clean the chain while it's still on the bike the main draw of those devices? Or are they primarily for light cleaning and removing loose dirt particles?

I've used one before and wasn't impressed with its cleaning abilities (A quick pass over the chain with a dry rag was able to remove far more grime than the chain cleaning device).

Maybe I'm just allowing my 2 stroke dirt bikes chain to get a little too filthy. Last weekend, I cleaned it out and removed at least a few cubic centimeters of black filth the consistency of modelling clay.

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