Bike Fitting at Loue Bicycles - Insole

Another area that Timothy from Loue Bicycles suggested I improve on during the bike fit would be the insole of the cycling shoes.

I have been using the RX8 gravel shoes since it was first launched in silver camo colour, and I liked it so much that now I have another pair in Cactus Berry colour. It is basically the best lightweight SPD shoe that you can get for road cycling or gravel riding.

So far I have been using the stock insoles, as I don't have any foot arch problems as far as I know. This means that I have been using the mid height insole that came with the RX8 shoes.

Timothy recommended that I get Sidas sole inserts to improve the support for my foot during pedaling. This will stabilize my foot during pedaling as he noticed that my foot was rocking from side to side during harder efforts. Before that, I decided to try the high insole that was also included with the RX8 shoes.

Stock yellow insert with mid height, and the red colour high insole which was included with the RX8 shoes.

Changed the yellow inserts to the red ones, just by pulling it off the main insole, as it is only attached by velcro.

Based on repeated testing (one side yellow one side red, swap sides, both red, both yellow), I was able to detect a small difference in the support. The thicker red insole was able to support the arch a bit more, but the difference is quite small.

Anyway, this was not the insole that Timothy recommended, which was why I still went to get the Sidas sole inserts that he recommended. The specific model that he recommended is the Sidas mid arch slim, which has a flat profile which is more suited for cycling shoes due to the limited internal space. It is not cheap, but it is worth trying it out to improve the pedaling efficiency.

Based on my brief research, most cycling shoes do not come with adequate support for cycling, as the soles are thin and simple. This aftermarket insole will improve the foot support.

Standard model for mid arch foot, and flat for low volume shoes such as cycling shoes which wrap snugly around the foot.

If you prefer a half sole instead of a full sole, you can cut it in half.

Adds some weight to the shoe, but if the weight is not on the bike, it doesn't count.

L size insole is for a foot size of EU 42-43, which is suitable for me as my EU shoe size is 42.

Sidas insole on the right, looks quite a lot bigger than the original RX8 insole.

The Sidas insole has a taller and larger support area, as can be seen from the larger green foam area.

The stock insole is like a piece of paper, compared to the Sidas insole. Let's hope the Sidas insole works well.

The Sidas insole is wider compared to the stock RX8 insole. I wonder if this would prevent the insole from fitting properly inside the shoe.

Using the heel as the alignment datum, I found that the Sidas insole is slightly larger. I marked the Sidas insole and used a scissors to trim off the difference as recommended.

After trimming the Sidas insole to follow closely to the shape of the original RX8 insole, it was fitted inside the RX8 shoe. It was rather difficult to fit the insole in properly, as the Sidas insole is less flexible due to the larger green foam. Also, there is an elastic band inside the RX8 shoe which also makes it hard to insert the sole properly.

However, I was pleased to find that once the insole is aligned properly, it actually fits pretty well inside the shoe. There were no creases or folds due to an incompatible shape outline.

Sidas insoles installed into the RX8 gravel shoes.

Once again, I tested the insoles systematically to see if it really makes a difference compared to the original insoles.

1) Sidas insole on one side, stock insole on other side

2) Swap sides and test again

3) Try both sides with Sidas insole

4) Try both sides with stock insole

I was able to feel a very big difference between the stock insole and Sidas insole. This was tested on various rides over a week, and the result is that the Sidas insoles really improve the stability of the foot.

With a better insole support, the foot is more stable during pedaling, instead of rolling around during harder efforts. This is a good improvement from the stock insoles. If you feel your foot rocking slightly from left to right, you may want to try a better insole to see if it helps to stabilize your foot.

Considering that there are thousands of pedaling strokes during a ride, it makes a lot of sense to consider the shoe and foot stability as well in order to maximize pedaling efficiency and comfort.