2

I am currently looking for ways to modify my bike.

I do have a straight handlebar equipped and I‘d like to switch to a drop down road bike handlebar. My drivetrain is built mostly from Shimano SLX parts

  • MT600 36/26 Crank (2S)
  • SLX M7020 Front Derailleur (2S)
  • SLX M7000 11-42 (11S)
  • Deore XT M8000 GS Rear Derailleur (11S)

  • BR-MT200 Disc Brake

  • SLX M7000 Shift Levers

I'm having troubles figuring out which drop down brake shift Levers (aka dual control lever) from the Tiagra or Sora series could work with those parts (2x11 and disc brake). Is there any possibility at all upgrading the shift levers without changing anything else in the drivetrain? I‘d like to stay with Shimano parts, if possible.

Kind regards

  • 1
    Are you aware that drop down handlebars will put your hands much further forwards? Unless you currently have a very long stem installed and plan to switch to a rather short one this won’t be comfortable. – Michael May 25 at 12:58
  • Isn't changing hand position the exact reason for switching to drop bars? – ojs May 26 at 9:37
3

What you are proposing to do is basically impossible. There is no documented compatibility between Shimano mountain and road groupset components.

The derailleurs have different actuation ratios (how far the cage moves for a given length of cable pull). MTB and road cassettes have different sprocket spacings. I've not read about anyone experimenting with Shimano road levers and MTB hydraulic brake calipers but I'd bet they are not compatible either.

You cannot replace the entire drivetrain and brakes. An 11 speed cassette may not fit on a MTB freehub body and a road crank won't fit in a wider MTB bottom bracket shell, and if you are contemplating buying a whole now groupset, just buy a whole new bike!

Another reason to not attempt this is that flat bar bike frames typically have a longer reach, as the distance from the head tube to the flat bar grips is shorter the the distance from the headtube to the hood or drop hand positions on a drop bar. Flat to drop bar conversions typically need a very short stem which can negatively affect the steering.

| improve this answer | |
  • thank you for the explanation - sounds reasonable and to be honest just as I feared... Sounds like I‘ll have to look for a whole new bike then. – Xylose May 25 at 14:26
  • @Xylose I have "read about someone experimenting Shimano road levers and MTB hydraulic brake calipers". Hence my two links to the products that enable that in my answer. See #3 at twowheellifestyle.com/… No need to fit a road cassette on an MTB hub. – Vladimir F May 25 at 18:27
  • As for shifting ratios, having a conversion device like the Tanpan (from Wolf Tooth) can fix such issues in 10 and 11-speeds. – Gregory Leo May 25 at 19:11
  • @Xylose its not impossible, but its excessively expensive. Generally its cheaper to buy a second bike than swap out an entire groupset, unless you got all the parts from a wreck/donor or on clearance somehow. – Criggie May 25 at 20:23
  • @argenti you might want to moderate your 2nd sentence. Its not correct at 7/8/9 speed or for 11sp DI2. Also all Shimano brake disk brake calipers are inter-compatible you just change the hose for the narrower version for Road sti's. – Secret squirrel May 26 at 7:34
2

A possible solution is this pair of brifters GX – Compatible with Shimano Dyna-Sys MTB Derailleurs

GX Shifters are sold as pairs and are compatible with Shimano 10 or 11 Speed Dyna-Sys Mountain Bike derailleurs. You can select from double/triple chainring, and short/long pull brake travel, and 10/11/12 speed.

However I have no experience whatsoever with them or even with the company, so I am just saying "a commercial solution may exist".

I would say that staying with Shimano parts is next to impossible, and I second @Michael suggestion about carefully changing bar AND stem. Your wrists should stay more or less in the same position on the drops as they are now.

| improve this answer | |
2

There are three paths that each have pros and cons.

  • Microshift BS-M11s with your existing derailleurs and switch to either mechanical brakes or Hylexes.
  • The Gevenalle levers mentioned in EarlGrey's answer and switch to mechanicals.
  • Any hydro 11spd STI with a Jtek Shiftmate 8. The FD will be a minor kludge but typically can be made to work fine in this direction on a double. You'll be trying your luck combining the STI with the BR-MT200. They're not listed as compatible but a lot of people run such mismatches. If you don't like it you can then just switch to a compatible caliper. Albeit functional, MT200s are extremely basic anyway; you don't actually have a lot of money tied up in them. If what you really want is hydro STIs with your existing gearing and a clutch, I believe this is the only way to get it. I don't believe the Garbaruk GRX cage would help here if running a double is what you want to do, because it mainly exists to make RD-RX812 clear a 50t cog in a 1x (which may be another way to get where you want to be anyway, and note there that then you're not buying a left STI). It would add a little total capacity, but probably not enough, and it would make your shifting bad with the 42.

There are no Sora or Tiagra STIs that help you here.

| improve this answer | |
0

For hydraulic disc brakes you need at least Tiagra 4700. Lower series only support mechanical brakes. You need the ST 4720/25 levers - but that would only give you 10 speed. You need the 105 series for 11 speed.

But you need to be careful with the MTB derailleur. No road groupset has the same actuation ratio even if they use the same cassette (like GRX). You will need some third-party products for the cable-pull ratio
https://www.wolftoothcomponents.com/products/tanpan
http://www.jtekengineering.com/shiftmate/shiftmate-8/
These are made precisely to allow road shifters and MTB derailleurs. This is a useful combination for 1x setups. Especially before there was GRX.

The brakes are also distinguished road/mountain and I do not personally know about their compatibility with the other type of levers. But many people report they work together.

| improve this answer | |
0

There is one foolproof option but getting a new bike is probably cheaper.

You could get GRX or Ultegra DI2 hydro STI's on your drops. You would need to change your Rear Mech to XT DI2, Front Mech to XT DI2 and add all the associated parts such as battery and wiring. Cost would be around $1000 and you would probably struggle to get a nice fit and you'd need a very high rise stem.

Its a thing though - particularly on older MTB frames at 7/8/9 speed - see this thread here

http://www.retrobike.co.uk/forum/viewtopic.php?f=1&t=94356

Also google monstercross bikes.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.