Who knows why a chain gets lube on the outside?

[Fat Boab]

The only way to get an answer is to perform a set of experiments to determine the pattern [and cause - but that can easily be ascribed to forces (radial acceleration) acting on an object/material etc] of migration of lubricants on a chain.

Start with a clean drive train. Apply lube to rollers/bushings. Remove excess lube. Record (i.e. photograph) the chain at predetermined intervals. Observe results. Repeat the whole process. Test against a control sample (i.e. clean drive train with no lube). Compare and test results. Formulate a conclusion. Sleep tight.

 

What you might learn is that the lube will eventually migrate from the bushings/rollers to the rest of the chain. At 90 rpm cadence and a 32T chainrings, your 114 link chain make ~25 revolutions per min or 1.5k time per hr. Suppose that's enough movement to get a bit of wax displaced.

 

Or you could do as Newton suggested.....stand on the shoulder of giants? And do a literature review first.....as LongDonkey suggests, it's been studied before. 

[LongDonkey]

Given the viscosity of a lube, the rpm of the pedalling would have a very low impact on the migration of fluid. Especially as the centrifugal forces would push the lube to the tip of the link. Capillary action and surface tension (a a whole bunch of vibrations),would permit the fluid to creep back against centrifugal forces to the centre of the link. OK, think i have flogged this horse enough now.

[Hairy]

So an additional factor to consider .... and I am shooting from the hip here.

 

With the high frequency vibrations that the chain experiences through normal pedaling and then the forces from the road, etc ..... could this act as a crude "ultrasonic" action to move chain lube out from between the rollers and plates?

[LongDonkey]

mechanically bouncing lube around between chain component will happen yes. Not sure how frequency would assist this as most chain movements are fairly large (on a MTB anyway). Small vibrations on the section under tension will have higher frequency vibrations which might move lube differently.

[Flemish Lion]

Where is JB when you need him 

[Hairy]

and a sort of "whiplash effect" on the chain when riding over irregular terrain ... i.e all of SA's bloody roads 

[Warren_G]

So an additional factor to consider .... and I am shooting from the hip here.

 

With the high frequency vibrations that the chain experiences through normal pedaling and then the forces from the road, etc ..... could this act as a crude "ultrasonic" action to move chain lube out from between the rollers and plates?

Good thinking Hairy, high frequency vibrations on the chain under tension should shift lube which means it would also depend on what gear you're turning?

 

Sent from my SM-G930F using Tapatalk

[Hairy]

Good thinking Hairy, high frequency vibrations on the chain under tension should shift lube which means it would also depend on what gear you're turning?

 

Sent from my SM-G930F using Tapatalk

there is only one gear .... the big gear

[Goodbadugly]

It is like the ANC wondering why people with money sent it overseas. And don't keep it on the inside of the country.

All the grinding and churning, junk status, promises of taking over the banks, land reform makes people uncomfortable.

Maybe  the lube feels uncomfortable on the inside of the chain

[SwissVan]

The only way to get an answer is to perform a set of experiments to determine the pattern [and cause - but that can easily be ascribed to forces (radial acceleration) acting on an object/material etc] of migration of lubricants on a chain.

Start with a clean drive train. Apply lube to rollers/bushings. Remove excess lube. Record (i.e. photograph) the chain at predetermined intervals. Observe results. Repeat the whole process. Test against a control sample (i.e. clean drive train with no lube). Compare and test results. Formulate a conclusion. Sleep tight.

 

What you might learn is that the lube will eventually migrate from the bushings/rollers to the rest of the chain. At 90 rpm cadence and a 32T chainrings, your 114 link chain make ~25 revolutions per min or 1.5k time per hr. Suppose that's enough movement to get a bit of wax displaced.

Simplified

Karate kid

Miyagi

Wax on... wax off

[Colin H]

Chain lube is a fluid and will flow through capillary action and through surface tension. The fluid sits in the small gaps between the rollers and the links, and as the chain goes through the drivetrain these gaps get smaller on the tension side and larger on the slack side.

This causes a "pumping" type of action and the fluid flows out of the small caps to larger gaps, and some of it goes to the outside of the pins and finds the outside of the plates. Then the creeping motion of the fluid is helped by the vibrations of varying frequencies through the chain.

By definition the fluid (lube) on the outside of the chain is evidence of too much lube in the initial application. This "too much lube" is not totally avoidable as we cannot abbey the lube directly to the gaps between the metal surfaces as they are hidden. SO we apply lube and it flows into the gaps where it is desired. 

The excess should then be wiped off. No lube is needed on the outside of the chain, just in the places that the metal plates and rollers rub against each other.

 

The merits of oil as a lubricant of choice in the application where two metal surfaces rub against each other under high pressure is documented and proven. The negative of this proper lubrication is that it can be messy.

But in order to keep adjacent moving metal surfaces apart, and thus reducing wear, a lubricating film of an oil is required.

[(Deon)]

Something I've been pondering recently on long, slow rides:

 

Why does lube paste itself on the outside plates of a chain when it is applied between the links?

Gosh, just how slow do you ride??!

 

[carbon29er]

Gosh, just how slow do you ride??!

 

Too slow. But it's time to think about the why's of life.

[Capricorn]

my nightshifted mind is not putting emphasis on viscous creep, capillary action etc, but rather macroscopic effects such as mechanical reduction in volumes between chain rollers, bushings and pins, which squeezes lube out, and contact between chainring/cassette teeth and chains squeezing out more viscous forms of lubrication.

Once mechanically pursuaded to leave the variable volume between rollers and pins, other macroscopic effects such as gravity and centrifugal forces, likely act in combination to result in transfer to the outside plates when the chain changes direction: an accumulation of lube that was maybe at the bottom of the chain, would after passing the chainrings or cassette and rear mech, would now be at the top. The chain plates are not guaranteed to be completely vertical due lateral movements of the chain, and thus this accumulation has equal chances of being drawn downward by gravity and/or centrifugal forces down the inside and outside surfaces of the chain plates, hence the appearance of lubricating fluid on the outside plates  over time.

 

Lube junk cakes on the outside plates because those surfaces are almost always exposed to crap coming off the riding surface with very little chance of being 'wiped' clean by other drivetrain components, unless you are a DH rider with a chain device packed with moto-foam to stop that chain rattling against the inside of the top guide.

 

in a nutshell, i need to go home and sleep!

[Thor Buttox]

It is the 'fan effect' of the turning spokes. That blows.

[Fat Boab]

It is the 'fan effect' of the turning spokes. That blows.

 

But it also sucks......