Don’t Do This Conversion If You Have STI Shifters 

from Rookie’s Keyboard

Hello, friends

Today, I am going to talk about a conversion that some uneducated rookies might try to do, namely – trying to mount brake-shifters such as STI on non-drop bars (e.g., risers, flat bars…etc.). 

I am about to tell you why this isn’t ideal and save you a lot of time all while providing you with info nuggets regarding STI style shifters that will help you avoid other errors too.

Let’s go.

Ergonomic Nightmare

Brake-shifters are made for drop bars and drop bars only. 

They have hoods serving as handles providing a comfortable riding position and quick access to the brakes.

If you put them on risers or other forms of flat bars, the hoods create massive ergonomic problems 

The levers of STI are designed to be perpendicular to the bars rather than horizontal.

In the second scenario, shifting becomes practically impossible or at the very least super uncomfortable because you have to push the switch levers down and up rather than to the sides.

Don’t be surprised if the tendons of your wrists and fingers start complaining pretty quickly.

Braking Performance Will Degrade Massively

Brake-shifters are built only for handlebars with curves. When you install them on flats or risers, the levers end up hitting the bars before completing their engineered travel.

That’s bad, very bad.

The rider is left with two options – to pre-set the brakes to the point where the pads are almost rubbing against the rim/rotor or to bike without having the option to “hit the brakes” 100%.

In other words, you are choosing between insufficient braking power and poor brake modulation.

The modulation of a brake gives the rider control over the braking force.

If there’s too much modulation, the levers will bottom out before full braking power has been reached.

If there’s too little modulation (as in this case), the braking feels like flipping a light switch. The brakes are either OFF or ON.

The Clamping Areas Don’t Even Match

Drop bars operate with 23.8mm clamps whereas flat bars have a 22.2mm clamping area. 

Of course, this can be circumvented via a shim around the bars.

I know that some people may find this option non-aesthetically pleasing, but it’s needed to securely tighten the bars.

Alternative Solutions

Sorry, there isn’t a logical and safe way to mount brake-shifters on risers, however, if your actual goal is to convert a road bike from drops to flats, consider the following options:

  • Flat Bar Road Shifters

Those are trigger shifters built specifically for road bikes with flat bars. 

They pull and release just as much cable as STI shifters and have smaller diameter clamps.

  •  1 Road + 1 MTB Shifter

Shimano’s 8, 9, and 10-speed rear road derailleurs have the same rear shift ratio as Shimano’s 6,7,8 and 9-speed MTB rear derailleurs.

As I’ve said in other posts, the shift ratio shows how much the derailleur moves per 1mm of cable pull or release by the shifter. 

If two derailleurs have the same max cog capacity and rear shift ratio, they’re functionally interchangeable.

If your road bike has 9 speeds or less, you can combine an MTB shifter with the cassette.


The front derailleur, however, demands a dedicated road shifter for optimal shifting experience.

If you aren’t against a retro setup, you could roll with a friction shifter mounted on the stem, the downtube, or the bars. 

Friction shifters aren’t segmented into clicks and allow you to mix road and MTB parts.

Note: There are also thumb friction shifters, albeit they ain’t exactly easy to find.

This wouldn’t be my choice (I am a big fan of downtube shifters), but it’s an option nonetheless.

Below is a list of thumb friction shifters:

ModelNumber of Speeds*Weight
Sunrace SLM105-7126g
Falcon Friction5-7N/A
Dia-Compe ENE Thumb Shifters8-10116g
Microshift Flat Bar Shifters9-10110g
Shimano Deore SL-MT62 5-7N/A
Shimano SL-M1505-7N/A

Alternative Handlebars

If you want to get away from drop bars while keeping your STI shifters, you could also consider two alternative handlebars:

  • Mustache Handlebars
Mustache handlebars

Mustache handlebars combine flat and drop bars. They can work with STI as far as the braking is concerned, but the shifting will be unusable. Most mustache handlebar users rely on regular road brake levers + bar-end shifters precisely for this reason. 

Bar-end shifter
  • Sparrow Bars

Sparrow bars are very similar to mustache bars. The only difference that I can see is that they’re shorter and have a more pronounced drop. 

There you have it friends – another informative article on rookiejournal.com

Until next time

– Rookie


Posted

in

by

Tags:

Comments

Leave a Reply

Your email address will not be published. Required fields are marked *