Are there any MTB style flatbar trigger shifters that are compatible with Shimano 4600 road components?
The Shimano SL-4600 are flat bar shifters for the 4600 road components.
SL-R780 and SL-R460 shifters are also listed by Shimano as compatible, so you have a couple more options than I first thought.
IIRC mountain bike 10 speed shifters use a different pull ratio so all are off the table, which you probably know hence the question.
Even the new 4700 shifters use a different pull ratio to 4600 so don't be tempted to use the SL-4700 version.
Shimano use several pull ratios for their shifters/derailleurs
- 6-9 speed road/MTB (aka standard ratio) & most 10-speed road
- 10 speed MTB
- 11 speed MTB
- 11 speed road (and Tiagra 4700 (10-speed))
As 4600 uses standard ratio, this rules out 10-speed MTB (different ratio), and obviously 9-speed.
4700 is ruled out because it uses the 11-speed ratio.
This leaves 7800, 7900, 6600, 6700, 5600, 5700, 4600 as the road groupsets using standard ratio.
The relevant parts:
- SL-R460 (2x10)
- SL-4600/SL-4603 (2x10/3x10)
- SL-R770 (2/3x10) - this one requires a special front derailleur the FD-R770/R773
- SL-R780/SL-R783 (2x10/3x10) - multi-release, but basically the same quality level as the cheaper R460/4600 (choose based on colour)
At least Tiagra 4600, 4700; Sora R3000 and Claris R2000 have flar bar shifters available in their line ups, presumably for use on road-oriented hybrids, commuter or fitness bikes.
Drop bar shifters have the component code
ST-[series code], flat bar shifters
You can look all this up on the Shimano line up charts.
To figure out what is compatible with what, you can look at Shimano's compatibility charts. As an example, open the Rear Drivetrain chart and search for 'SL-4600', you'll see it's compatible with the RD-4600 derailleur.