bOsscO

Thinking about changing my curved road handlebar over to a flat bar. Is it easy to switch up my 9-speed Shimano Tiagra FlightDeck brake levers and shifters (on my road bar) to something like 9-speed XT levers and shifters? I plan on only changing the handlebar components and leaving the deraileurs, cogset, calipers as is. I know Shimano makes road specific components for flat handle bars:

https://bike.shimano.com/catalog/cycl...=1156887899118

However, in Vancouver, mt.bike components are a dime-a-dozen and WAY less expensive. thoughts?

well biked

The Shimano "road" front derailluer requires a slightly different cable pull than the "mountain" FD shifter. Might work, I don't know, but it is slightly different than the road shifter. Also, mtb brake levers pull a different amount of cable than road brake calipers require-

bOsscO

If mt.bike levers pull 'more' than road leavers, then wouldn't it be a matter of adjusting how much I pull?
" " 'less' " ", then they wont' work very well at all.

What about the rear deraileur?

Grand Bois

The rear derailer will work just fine. I have an Ultegra on my MB-2. Mountain levers work just fine with road calipers. I don't like drops, so I know that from experience. Try your road front derailer with the mountain shifters. If you can't get it to shift acceptably, you can switch to a mountain derailer. They're cheap. My Peugeot MTB has a 105 FD on it and it couldn't possibly shift any better. I've read that there is a problem with the curvature of mountain front derailer cages being different from the cages on road derailers, but I've got a 105 and and XT here that look identical to me.

well biked

Just curious, but are you talking about levers on a mtb that were originally used with cantilever brakes? If so, then the cable pull would be compatible with road calipers. I can't say I've ever used modern mtb brake levers with road calipers, but my understanding is that because the road calipers have much less mechanical advantage than linear pull brakes (v-brakes), to try and use them with modern mtb levers would require a more than desirable degree of force at the lever to get effective braking-

Grand Bois

You're right, levers for linear pull brakes are only good for linear pull and mechanical disk brakes. I'm a vintage guy. I tend to ignore the really modern stuff like linear pull brakes and hubs with more than seven cogs.

TO11MTM

As others have said, you'll most likely need a new front derailleur. There's a reason flatbar road bikes don't use regular shimano road derailleurs... you also will not be able to use standard Cantilever/caliper brakes with current Shimano XT brake levers... Personally, I'd vote to get seperate brake levers in any case; there's nothing as irritating as having to replace both the brake lever and shifter because one part or the other broke...

Ray Dockrey

I asked the exact same question to Sheldon Brown several months ago. I have a set of Deore nine speed shifters and brake levers off of a mountain bike and here was his response:

The brake levers will not work properly with caliper brakes unless you install Inline Travel Agents.

See: https://harriscyclery.net/page.cfm?Pa...ils&sku=BR0330

The rear shifter will work fine, but the front shifter won't index properly unless you replace the front derailer with an R443 model.
See: https://harriscyclery.com/derailers-front.html

well biked

But the travel agent is for just the opposite application: using road levers with linear pull or mechanical dics brakes, is it not?

Grand Bois

The OP doesn't have the parts. He said he can get them cheap. He just needs to be sure to get levers made for cantilever brakes.

As for the road derailer with mountain shifters, here's my wife's mountain bike. That's a 105 derailer. The shifters are SRAM gripshifters. It isn't supposed to work, but it does.

bOsscO

judging by the pic/description, that's what I gathered too. I want to go the other way: road (canti) calipers with flatbar levers.

I can find flatbar canti-levers in any used shops bargain bin: no problem there. As for the R443 FD, I realize they exist but that's what I'm trying to avoid. Thanks for everyones help, 'specially YOU Dirtdrop...
would you believe this whole idea is revolving around getting this older XC stem on the front end of my Specialized Allez?

LóFarkas

Switching to a 25.4 road bar to go with that stem would be a bit simpler

Retro Grouch 

I disagree. Lots of factory bikes were sold that had road derailleurs and mountain rapid fire sifters before Shimano saw fit to produce flat bar road shifters.

godspiral

I would price and testride flatbar "fitness" bikes (light hybrids), and feel out the resell value of your bike as a comparison. It could come close to a free upgrade.

bOsscO

It maybe hard to tell from my pic of the stem, but it's a single bolt clamp...so it'll only take a flat bar (I tried to thread a riser through an only managed to scratch up the paint).

As for reselling my bike, I've spent all summer looking for a 62cm roadbike and found this Allez on Craigslist...I just bought it. I'm 6'-3" with long legs and it fits me perfectly so I'm keeping it. I looked at hybrids and 'fitness'frames and not only had trouble finding one big enough, but I also had trouble finding one with out susp.forks.

LóFarkas

Ah, I see. It's a closed clamp or whatever they call it. That wouldn't be a problem, but it's so crazy wide that you'd probably have serious trouble getting any bend through it. You must love this stem

dannyg1 

Is your wifes bike running 7, 8 or 9? Please let it be 9; then you can tell me which chain you're running and I can do exactly what I want to do to my friends bike.

HardyWeinberg

I have shimano 'flatbar roadbike' shifters w/ regular tiagra front derailer right now, works great. Well, no different than it worked w/ the officially compatible front derailer. I wonder what I would get upgrading from 440 to 660 shifters.

I do gather that the mtn bike shifter does not have the half-stop for trimming between the middle and big chainrings. That's a shifter issue, though, not a derailer one.

cs1

I'm using 7 sp thumbies, they work fine. No ft der problem with them. A more expensive solution is to use 9 speed barcons on Paul Thumbie adaptors.

Tim

maddmaxx 

The quickest way to shift a road bar to a flat bar is to install a set of Shimano flat bar shifters/brake handles. Everything continues to work as you have it now. All the various ratio's are satisfied.

If you choose to go with mountain controls, then the R443 front derailleur is probably going to be necessary. Mountain front derailleure have the right ratio but on many if not most road frames they will not have sufficient clearance to operate between the rear tire and the seat tube. Mountain fronts have a kink in the "pull" portion of the operating lever that uses this space. Road derailleurs have a more straight arm that operates on the drive side of the tire and does not require the space.

Again if you choose to use a mountain brake lever than a lever with adjustable ratio's works best. Avid speed dials and Shimano levers with a three position cable anchor screw handle this chore just fine. The pull and torque of the levers will work well with road brakes when adjuster inward toward the pivot point of the levers.

If you like to use Grip twist shifters, then SRAM x.7, x.9 and x.0 shifters will work with any front derailleur as the have 8 "clicks" on the left shifter to handle 3 gear positions. Instant trim. You will however have to change the rear derailleur to accomodate the SRAM 1/1 ratio there.

Most of these rules apply to triple setups with indexed shifters, I'm not sure what can be made to work with doubles. If you use barcon shifters with friction on the front then almost anything is possible. They can be mounted on a flat bar with a bracket called a "thumbie". The end result looks very much like a mountain thumb shifter but with friction capability.

Sorry to be so long winded, but these suggestions work.

maddmaxx 

Sorry, there is an error in my previous post. Shimano flat bar shifter/brake levers require the use of the R443 front derailleur as the shifter ratio is altered to the mountain ratio.