In an effort to reduce the sales price of the ChainMate, I had a look at redesigning it.
Not drastically, as the original design works very well, but I had to make the ChainMate more flexible so I could reduce the number of variants. This would allow me to get larger quantities made, thus reducing manufacturing costs.
I currently have around 34 different sizes of ChainMate. I needed to streamline the range to reduce costs and to make them more versatile for the user – needless to say, I had many sleepless nights wondering how.
Then the idea came to me to fit a spacer between the smallest width ChainMate – the 520 – in order to make it fit a 525 and 530. After a lot of time spent recalculating sizes and redrawing, I came up with the correct sizes that allowed me to place a 1.5mm shim between the two halves to enable it to fit a 525 chain and then another 1.5 mm shim to fit the widest chain – the 530. I had reduced the number of variants by two-thirds!
However, I still had all the different sizes due to the different radius of the rear sprocket. I then tried a 40T ChainMate on my Kawasaki 41T rear sprocket and found that it would turn quite easily. Initially, I wondered whether it would be a good idea to buy rear sprockets in all the sizes for testing purposes, but quickly came to realise that this would cost a small fortune. Going back to the drawing board, I worked out all the different radii for the sprockets with the chain width added, then drew up a set of four templates, with sprocket sizes from 36T- 51T. These were lasered out of aluminium – a lot cheaper than the sprockets themselves. Once I had the templates I needed to experiment with different radii, I decided that I could not make a ChainMate that fitted a 36T sprocket and a 51T sprocket, as the difference in radius is 74mm. This would compromise the snug fit needed around both areas. Instead, I decided I could make a range of 4 different sizes going from 39/40/41T, 42/43/44T, 45/46/47T and 48/49/50T. Using the shims, this enabled the ChainMate to fit 36 different chain and sprocket combinations, resulting in reduced manufacturing costs that I can pass onto the end user.