Shimano RX8 vs RX6, and RC9 vs RC7 Shoes

Here is a brief comparison of a few different Shimano cycling shoes. For gravel usage, there is the top grade RX8, versus the cheaper RX6. As for road cycling, there is the top grade RC9 (S-Phyre) and RC7. I happened to see all these models in the shop, so I decided to do a shoe comparison based on what I saw.

I really like the RX8 gravel shoes, as they use the SPD system instead of SPD-SL, which makes it much easier to walk in. Also, they have the sleek look of road shoes, without the bulk and weight of MTB SPD shoes. In fact, I like the RX8 gravel shoes so much that I have many pairs of it (and counting)!

RX8 in Silver Camo colour

RX8 in Cactus Berry colour

RX8 in Bronze colour

Shimano introduced a few new models of gravel shoes earlier this year. The improved RX801 (previously RX800, also called RX8), as well as the new mid grade RX600 (or RX6) version.

Both are RX6 gravel shoes in different colour. SRP is SGD 199.

Birdy AXS: Chain Length, Freehub Grease and QR Axle Changes

Final post on the Birdy AXS 12 Speed folding bike! At least for now, until some new project or ideas pop into my head.

Throughout the whole upgrading process from the stock 9 speed Birdy City, I have learnt a lot about the Birdy folding bike. Especially for the folding design, where it is different from any other bike.

There were a few issues which were not fully resolved earlier, but they have now been fixed. 3 of the problems have been highlighted below, along with how I solved them.

First issue was the chain length on the Birdy drivetrain. As I transplanted the SRAM AXS 12 speed drivetrain from the Fnhon DB12 folding bike, I reused the existing chain as the mileage was quite low.

However, the chain stay length of the Birdy is longer at 430 mm, compared to the 400 mm of the Fnhon DB12. Therefore, using the same chain length with the same cassette and chain ring, on a longer chain stay, makes the rear derailleur cage stretch out too much.

At the largest sprocket (lowest gear), the rear derailleur cage is very stretched out and looks over the limit.

Birdy AXS: Outdoor Pictures and Gear Ratio

With the Birdy AXS 12 speed completed, I can ride it around to many different places, and take some nice pictures. Here are some of the pictures with the fully upgraded Birdy folding bike with 20" 406 wheels. Compare this to the pictures that I took with the stock Birdy City bike.

Simple but attractive dual colour scheme, with a Sky Blue frame colour and all black components.

Long ago, I had the Dahon Boardwalk with lots of gold bling on it.

Birdy AXS: Birdy Dimensions and Weight after Modifications

After completing the modifications to the Birdy folding bike in the earlier posts, there are some bike dimensions that have been altered. This is largely brought about by the change in wheel size from 18" 355 to 20" 406, and also a few other component changes.

Fully upgraded Birdy folding bike with a 12 speed drivetrain, carbon wheelset, wireless shifting and full hydraulic brakes.

Birdy AXS: Wheel Size Comparison - 18 Inch (355) vs 20 Inch (406)

One of the major modifications that you can do on the stock Birdy folding bike is to change the wheel size. For most bikes, when you upgrade the components, the wheel size remains unchanged, since the frame is only designed to fit one wheel size comfortably. In the case of the Birdy frameset, the stock 18" 355 wheelset can be swapped for a larger 20" 406 wheelset. This means that the rim diameter is increased from 355 mm to 406 mm, a 51 mm increase.

However, if the wheel outer diameter (inclusive of tire) is directly increased by 51 mm, it will not fit in the frame properly when folded. Therefore, using a larger rim diameter needs to be complemented by a reduction in tire height. In other words, swapping from an 18" 355 rim to a 20" 406 rim requires the tire to be changed to a slimmer type (which is also shorter in sidewall height).

Therefore, if you are looking for a more comfortable ride, using a smaller 18" 355 rim will allow a wider tire to be used for more air volume and comfort. On the other hand, if you are looking for a sportier ride with lower rolling resistance, go for a 20" 406 rim with slim and slick tires.

This dual wheel size compatibility concept is the same as that found on the Ascent Bolt/Intrepid mini velo bikes, where you can go for a smaller 406 wheel with very wide tires, or a larger 451 wheel with slim tires.

In my case, I wanted a larger 20" 406 wheelset for faster road riding, which is why I changed to the Ascent Cirrus Elite carbon wheelset. I also chose the Panaracer Minits Lite tires for low rolling resistance and reduced weight.

Stock 18" 355 wheelset on the left, new 20" 406 wheelset on the right. The difference in wheel diameter is quite obvious. Rotor diameter is the same at 160 mm.