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Thursday 28 January 2021

Worn bike drive train

 I've seen a few posts on Facebook which ask, "is my chainring worn out", "should I replace my chainring."

I have just replaced a crankset, probably beyond its expected lifespan, which shows clearly what a worn out chainring looks like.

Side by side, the new and the old. Surprisingly, that chainring was not skipping. I only looked at it because the whole drive train sounded clunky!

I am pretty sure this got to that stage quickly because the chain was worn out. I checked the chain a month or so ago but in that time, it has gone from acceptable to thoroughly useless. I blame the wet mud at this time of year.

A chain guide is the best way to check a chain and easy to use.

I was interested in looking at how a chain wears. I have heard people refer to chains as stretching. This is misleading because the components of the chain do not stretch but the pivots wear smaller allowing play. If you push and pull two links you can see and feel the movement of the links. A new chain has virtually no movement along the length of the chain.

In the case of a severely worn chain, if you pull it taught and offer it up against a new chain, you can see how much play there is.


Sunday 24 January 2021

Ring IR beam modification

Ring Security, as far as I know, do not have an infra-red beam solution for things like driveways.

It was a fairly easy job to modify a Ring door sensor to connect to a commonly available IR beam.

I'm sure I'm not the first, nor will I be the only, person to have made this modification.

The door sensors use a standard reed switch, which is just on and off. The IR beam, that I have, just connects or breaks a relay switch, so is ideal to connect in to where the reed switch would normally be.

I soldered on a pair of wires in place of the reed switch.

I used a water proof box to house the modified door sensor and ran the lead to connect it to the IR beam. Works perfectly.