Indoor Bike Improvement #4 - Improved Shifting

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 4 of 10 - Better Shift Buttons

The SB20 indoor bike has OK-ish shift buttons.  IMHO: The blip buttons under the handlebar tape are fine. The brake lever buttons are mediocre.  

Brake Lever Buttons

There are 3 programmable shift buttons under the hoods on each brake level. I find they lack tactile feedback. You can't be sure if a button was pressed by feel alone. Also: The buttons on each lever can be difficult to distinguish - particularly in an intense sprint.

Here are my modifications:


1. To address tactile feedback issues, I made cutouts in the brake hoods with a X-acto knife.  

2. I extended the buttons with J&B Epoxy putty. Each button has a different shape: round, pointed and flat. I can now identify buttons by feel.

3. I replaced the hoods and painted each button a different colour to make them visually distinct.

The result is literally a "worst-to-first" transformation. The buttons now trigger with 100% reliably. It is also much easier to press the intended button without looking.  

Blip Buttons

The under-tape blip buttons can be vague or mushy. It can be hard to tell if your finger is properly positioned. Added to that, if you change handlebar tape, button performance suffers.

FWIW: I'm not a huge fan of the original Stage handlebar tape. I think it's too thin and can be slippery when wet.  I am fairly certain Stages choose this style of tape to improve the blip button performance

The original Stages tape is non-porous. Stages says it helps block corrosion. My experience has been opposite. When sweat and moisture gets under the tape, it doesn't dry thoroughly, potentially leading to more corrosion.  I am happier with breathable foam tape. It dries quickly and doesn't trap moisture. It feels better too.


4. I moved the blip button pads from the drops to the underside of the top bar.  I then cut openings for each button in the handlebar tape (it's not the cleanest job I have ever done - the next version should be better 

Either way, the buttons are not normally visible). I used "Goop/Shoe Goo" adhesive to glue rubber pads (kitchen cupboard bumpers) over each button. This greatly improved precision and feedback.

Dealing with Sweat

The blip buttons dry nicely thanks to breathable handlebar tape. The exposed lever shifter buttons do not appear to collect sweat. Since the buttons are no longer hidden under the brake hoods, I can now routinely spray with electronics contact cleaner (I've been using the same can since 1985 🤣).



Contract cleaner help the buttons work even better.  BTW: You can also use isopropyl alcohol.    


* * * * * *

... Something else you may find interesting ...

Adopting SRAM Configuration

After using the top bar buttons for a few weeks, I started to see value in adopting the SRAM shifting philosophy: Left button(s) = lower gear; Right button(s) = higher gear. This works particularly well with the 1 x 25 Dream Drive configuration I have used since day one.  



5. I eventually settled on the following SRAM Inspired settings in Stages Cycling app > Devices > Setups:

⏪

Outside/Upper left button

-3 gears smaller


◀️

Inside/Lower left button

-1 gear smaller


 +1 gear bigger

Inside/Lower right button

▶️

 +3 gears bigger

Outside/Upper left button

⏩️

5b. The blip buttons follow the orientation of lever buttons i.e., when the top lever button shifts to larger gear, the nearest blip button will do the same. You may need to physically reverse each button pad before re-taping depending on how you customized of the lever buttons. 

Using this Setup

It took about 10 minutes to get used to this unique shifter arrangement. The big advantage for me: In a sprint, I no longer move to a smaller gear if I press the top button by mistake. The worst outcome: a less than optimal gear that is at least it is in the right direction. 

--------- UPDATE 📣  January 2024 ---------

I noticed that the Stages brake lever presses the orange Zwift play button to trigger the Zwift brake function without affecting steering. Very convenient if you ask me.



I had to disable the SB20 braking function using the Stages Cycling app. 

Some people use this feature in sprints to effectively pick a higher virtual gear. Instead I find that accurate shifting to an exact gear works better for me. 

🤓 For sprinting, I prefer to shift to my optimal virtual gear and pedal at my optimal cadence. I modified the OEM shifter buttons to make them more reliable (see link below). Optimal gear and cadence is determined by recording sprints and picking highest watts from previous rides or by doing dedicated tests. Using the Stages brake causes me to reduce cadence and always produce lower watts. I pedal at 120-130 RPM in sprints so I never lug the pedals like many do when "adding the brake".

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