Wednesday, June 19, 2013

Bicycle Chains and Oils

clean your chain!
After too many years of testing different kinds of chain lube I have decided there is only one way to make your chain last longer. Keep it clean; if it makes your fingers dirty and greasy it is way too filthy. There is no substatute for using a brush washer regularly. 3-n-1 oil was originaly a chain oil. All the high tech chain oils are rip-offs.

There is a kind of chain that is galvanized to keep it from rusting. But it may wear-out sooner because the galvanized coating is ruff.

For a motorized bike a good belt drive would be great. But they need to be kept clean also. So building a cover for it would be needed.

It is good to use quik links and carry a removal tool to open the chain when needed. This and keeping the chain clean will make fixing a broken chain much easyer. Some chains are easyer to replace a pin the old way than others, but I do not know which they would be. So after braking my chain several times with my new motor, I decided to stop shifting the rear gears, because the not using an indexed shifter makes it very difficult to not jerk the chain so hard that it can brake the chain.

PTFE Molecular Structure

The STP will make light oil into a viscous mess so use only a very small amount to keep it in contact with the chain bearings.

Longest lasting chain oil you can make.

I have tried all kinds of chain oil, only one lasts more than a week for me, and it lasted only two weeks. When I went to a chemical forum they recommended using aluminum oxide powder in oil to make an extremely viscous goop with staying power beyond your wildest dreams (It lasts several months for my low mileage commuting, about a 1000 miles).

So I have been using this mix of STP (w/zinc oxide) and a thinner “sewing machine” type of oil to thin it out a little bit. And finally I put PTFE in it. I clean my new chain with Naphtha solvent before applying this lube. And I have to heat the oil in an eye dropper bottle in hot water to get it to penetrate the chain. Of course this is only for on road commuting.

  • Racers need something more temporary made of wax and PTFE. Spray on wax lube maybe easy to apply, but it will bunch up and leave the chain un-lubricated in just a few days. You should clean it off the chain after every use.
  • If you live with silica dust on the roads, you will be better off with no lube at all.
  • If you are a dirt trail rider, use the wimpy sewing machine oil that “could” clean your chain if you use enough of it. Buy it in bulk.
  • Motor oil has detergents in it, and was designed to thicken as it heats up. Not a problem unless your riding in the desert in the summer?
  • If you want your chain to last longer, keep it enclosed like Dutch Style Bikes. This may require internal gears also. But you will need to have one custom made for your bike.
On the Sheldon Brown site they tell you not to use aluminum in oil because they think it is abrasive. Aluminum hydroxide is a soft very small particle. It can't work as an abrasive!!! And racers will probably tell you that this viscous oil will suck so badly that it will slow you down! That is why I tell you how to do it your self, and forget about speed!!!

 keeping your chain clean is almost impossible, wax lubes must be applied every time you use the bike but the chain must be cleaned first. So if you really want to keep your chain clean, run it through a tube. But it is only easy to do on a recumbent bike.

    Go-Kart chains are #35 and #219 and are vertualy the same size. And none of the sprockets fit on a bicycle.

    But if you can rig a way to use them it is easyer to build a large gear reduction with them.

    From Cost-Benefit Comparison: Electric Bike Chain-Suck"

      With oil as a lubricant, the abrasiveness of the sandy road grit has hardly any physical effect because the particles that can get into the chain links are very small.

      Particles already in the link can hardly be removed by any cleaning method (not even with an ultrasonic bath). In order to prevent particles being transported into the link in the first place, the chain should be kept dry and clean on the outside by wiping it regularly with an oily cloth. Additionally, sprockets, pulleys and chain-rings should be kept as clean as possible because these parts are in direct contact with the rollers of the chain.
      Cleaning solvent will mix with the lubricant which in most cases destroys its lubricating feature; cleaning liquids which do not have 100% degreasing effect, such as diesel fuel are recommended.

Even so called lubes with a noticeable white wax film do not actually stay in the links long enough to lubricate your chain for more than a few days, and should only be used after lubrication. Dry-wax film reduces the amount of dirt sticking on the chain and partly protects the link against dirt and water.

This chain wax lasts only about one hundred miles when used to lubricate the links, but is very good for protecting the chain's outer surfaces from rain. Spray it on lightly to keep it from building up. And only after lubricating the links with viscous oil! 

chain construct: 

Pins inside full bushings of (six element) chains are well protected against lubricant depletion because both ends were covered by closely fitting side plates.

Some motorcycle chains have O-ring seals at each end. In the swagged bushing design where there is no continuous tube because the side plates are formed to support the roller and pin on a collar with a substantial central gap; In the wet, lubricant is quickly washed out of pin and roller then the smaller bearing area of the swagged bushing for the pin and roller can easily gall and bind when lubrication fails.

If I had enough money I would convert to a timing belt and internal gears.

Old chains lasted longer than the new narrow chains because they had more to wear away and because the amount of sprockets was less. Chain rings lasted longer also!

The friction savings would be minimal either way, since friction relates to the materials, and lubrication and not to surface area. Since the material is steel both ways, any difference would be tiny. But the bearing grade bushing provided for longer wear life.

 You wouldn't want a bushing chain these days (even if you found one) because your derailleur system wants more side flexibility than is possible with this design. Also, it would be difficult to produce a bushing chain narrow enough for today's requirements.

When it comes down to it, buy a decent (mid-quality) chain, keep it reasonable clean and lubricated, and replace it as necessary. With decent choices, drive-train maintenance costs will not be a major factor either way.

If you get a lot of mud and crud build up on your sprockets, you may as well take it to a car wash then use WD40. Then keep applying it every week, wiping off the extra.

For a typical large motor you need a 12-114 chain and sprockets which can only be found with go-cart sized chains. (#35)

E- Bikes:

     Ten speed cassette cogs are 1.6-1.7 mm thick, 9 speed 1.75-1.8 mm, 8 speed 1.8-1.9 mm, 5-6-7 speed 1.85-2.0 mm, BMX 3.2 mm thick.

The upshot is that a ten speed cog will wear about twice as fast as a BMX cog. The chains themselves, on new cogs, will wear internally at the bushings and pins, based on the quality of the chain. But since the narrower cogs wear faster, this will indirectly accelerate chain wear.

I have said this too many times. Somebody needs to produce a drive-train for high powered (over 750 watt) mid-drive bikes. A five speed cassette with cogs and spacers twice as wide as ten speed, wider idler spacers for the dérailleur, and a shifter with every other detent missing/filled to use BMX chain.

A 14-42 cassette gives nice even spacing, a 3:1 or 300% or 8-24 mph range (however you want to think about it), and a minimum of seven teeth engaged.

"Bushingless" chains have bushings; they're just stamped into the side-plates and therefore not a separate subcomponent. Bushingless chains are easier to lubricate, and allow the chain more side flex, so they're generally better for pedal bikes with dérailleur shifting.

Traditional chains with bushings have a lot more projected area in the bushing-to-pin interface, so they last a lot longer in single speed applications with good sprocket alignment, like track bikes or industrial equipment. You have to lube them through the gap between sideplates, which is sometimes tricky. That is one reason that they invented thin oil.

A BMX chain is basically what was used for dérailleur bikes for decades. My first road-bikes all had 5 speed rear freewheels. They shifted just fine with stiff, bushed chain that was basically indistinguishable from BMX chain. 

Modern ramped cogs would make that chain shift even better. Cog center-to-center spacing on those bikes was 5.5 mm. The center-to-center spacing of 5 cogs on a current cassette would be 7.9 mm. A chain as stiff as rebar would work with that much space.

Chains wear out sprockets, rather than the other way around. Once a sprocket is badly worn, then it can wreck a chain. So the thickness of the sprocket is much less important than the width of the chain bushing surface.

A narrower sprocket leaves more room for a 1/8" chain to deflect sideways before contacting the adjacent sprocket. So a wider sprocket isn't necessarily an advantage.

What is chain suck? The chain will try to cling to the sprockets causing the whole drive to bunch up and crash the bike. So it really is good to keep the chain very well lubricated.


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