Spline grease formulations

[natalena]

Just curious to hear if anyone uses PTFE in the spline grease "home brew" mix.

I ask because I use MoS2 and PTFE in a wax base to "cook" bicycle chains for racing, and it works splendid for reduction in sheer and compression stress at pins and plates.

There shouldn't be a heat issue at the drive shaft. Anyhoo, was looking at mixing 'x' grams of each into Molub-Alloy, and ripping some donut's in the local elementary school parking lot, disassemble and see if it's mo-betta.

[Laitch]

There shouldn't be a heat issue at the drive shaft.

What exactly does that sentence intend to convey?

[natalena]

PTFE has a decomposition temp about 400f, when it starts to gel.
I remember a conversation with some engineer-types that said working below 500f is required on plasticity applications vs Teflon amalgamations you'd see used in pans. Still pretty slippery stuff.

[Laitch]

Moly works by bonding with metal by heat of friction to create a secondary metal surface to inhibit wear. What role would the PTFE fill?

[natalena]

A micron layer of slip between the bonded MoS2/shaft material/female fitting. The idea come up while reviewing the wattage savings on bike chains, as they have a similar movement at the pin/plate. In practicality, I only re-wax chains every 500mi out of habit, and notice a dramatic increase in use life vs. petroleum lube. Perhaps it could help with drive splines.

[The Mighty Gryphon]

Moly works by bonding with metal by heat of friction to create a secondary metal surface to inhibit wear. What role would the PTFE fill?

I would be concerned by the compressibility of the PTFE under extreme pressure. 

IMO, Moly is the only way to go on splines where the pressure is a concern, the more moly the better.

[johnny]

greetings...

how many housepower at the sprocket... can you grab the chain without getting burnt after 200 miles in 100 deg temps... can it go 10 thou miles between chain lubes without noticable wear...

j o

[Laitch]

A micron layer of slip between the bonded MoS2/shaft material/female fitting. The idea come up while reviewing the wattage savings on bike chains, as they have a similar movement at the pin/plate. In practicality, I only re-wax chains every 500mi out of habit, and notice a dramatic increase in use life vs. petroleum lube. Perhaps it could help with drive splines.

A slip on a slip. That seems redundant and it might just slip away. What is required to adhere PTFE to a secondary metallic surface? Can it adhere?

The forces acting on a moto driveline are greater than those acting on a bicycle drive system—except maybe if somebody like you is on the pedals. :giggles  The problem with the Beemer's arrangement is lubrication castoff by centrifugal force. Using moly mitigates that effect by its plating action. That seems to be why so little is needed for application and why reapplication at intervals is necessary because the plating eventually wears off.

Let us know how well your blend adheres. Spinning donuts in the parking lot might not be enough action to determine the blend's efficacy. Rolling crullers from sea to shining sea—and back—might be a better test, but a journey of a thousand miles etc..

[natalena]

Thanks for the input guy's. I didn't seriously consider the PTFE compressibility at 1.6mu powder, but it's a great point, and I'll ask my engineer buddies. Been using 5 grams of Moly to 20 grams of Castrol Molub-Alloy for now.

The lube conversation came up, as we're always looking for an edge to reduce friction and make better use of available wattage in bicycle Time Trials. The obsession is the same level as shaft drive spline preservation. Flinging of the lube is also an issue, so it may not work for Brick's, but may end up on something Unique with chain drive.

You never know ... we invented a piece of rock climbing gear, the design ended up being used on aircraft canopy's.

[Laitch]

we invented a piece of rock climbing gear, the design ended up being used on aircraft canopy's.

:hail: