Can i mount a deore XT shift lever on a drop bar?

Question

I have shift levers Shimano Deore XT SL-T8000 for a 3 x 10 groupset.
The clamps are for straigt bars, 22.2mm. I'd like to mount them on a drop bar, which has ~24mm. The bike is from the mid-90s and much beloved, and originally had downtube shifters, but the old 2 x 7 groupset doesn't offer the gearing for the hilly region around here. Since the clamps are detachable, i was wondering if there are replacement parts with a wider clamp diameter. I'd be willing to widen them if necessary, since there seems to be sufficient material to drill them to spec, but i'd rather use something premade, if there is anything.

Does anybody know of suitable clamps for these shifters, or otherwise of other shifters that might work in the situation?

Answer 1

If you're interested in an alternate solution, there are some "alt-bars" that have the mtb-standard diameter but allow a more aero position. I have Surly's Corner Bar on my mtb/gravel hybrid bike. It works pretty well. It's not quite a full-on drop bar but it was a very inexpensive way to get more aero. A drop bar would have meant replacing the levers, which also would have meant replacing the derailleur and maybe even the brake calipers. So far I'm really happy with it.

Answer 2

You're correct that the 22.2mm clamp will not work on the wider drop bar. I don't know of any after market clamps that will replace the current clamp and fit the drop bar. For the Shimano XT, T8000, to replace the band on the shifter requires a new top cap assembly (the upper, outer portion of the shifter). The shape is very specific with matching screw holes, etc and the shift indicator, if present, is yet another separate piece that would need the correct connection holes to fit back onto a replacement clamp assembly.

Finally, the ergonomics of a flat bar shifter mounted on a drop bar are not ideal. They may work for some if mounted on the top, straight section of the bar (and we've seen how they won't fit a drop bar without extreme modification of the clamp band). Another bug-a-boo is that the T8000, utilizes the cassette spacing and derailleur shift actuation of Shimano mountain bike 11 speed, both of which are different from Shimano road 11 speed. This can be over come by using a MTB 11 speed rear derailleur and an 11 speed mountain bike cassette.

By now, it should be obvious that simply trying to use mountain, flat bar shifters has some hassles that make the solution more of a problem. You might be better served by acquiring "bar-end shifters." These are designed to fit into or on the ends of a drop bar. They're offered in 9,10, or 11 speeds.

Another option would be to get a 7 speed mountain cassette or freewheel, depending on your rear wheel hub design, that has a 34 tooth large cog.

Changing your current cassette to one of these would be the most economical solution as it only requires the purchase of the wide range cassette. The rear derailleur might be out of its spec limit for number of teeth of the largest cog, but typically can be made to work just fine by screwing in the B adjustment screw to get enough space between the derailleur jockey wheel and the largest cassette cog.

Answer 3

There are options the other way around (using a road groupset on a flat handlebar), but I'm not aware of options to use MTB components on a drop handlebar. The T8000 series is to my knowledge a niche product - and more aimed at an utilitarian audience than an enthusiast one, so I doubt there would be many aftermarket modifications for it.

If you want to avoid machining the clamp of the current shifters, I don't see many options:

• bar ends (least hassle solution): Microshift has one set that is compatible with 3x10 MTB groupsets.
• an "alt bar": that are bars with original shapes for flat bar components. There are not many options with clamps smaller than 31.8mm, but they exist (Surly Corner Bar for example).
• other shifters with iSpec mounts (iSpec mounts are mounts for shifter/dropper that are meant to be mounted with a bolt under the brake clamp), if you can 3D-print a clamp that is strong enough for the shifters with the matching mount (3D models are easy to find online). In that case you could use a M8000 front shifter and a M4100 rear shifter, that are both available with iSpec mounts (the M8000/M7000 won't work, as it is a 11-speed shifter). It starts to be more complicated, but depending on your local options, can be easier than machining a clamp.

But if the problem you want to ultimately solve is the range, rather than fitting a T8000 on a drop bar bike, why not a Microshift Sword 2x10? It's a recent 2x10 gravel fully mechanical groupset. It doesn't have as much range as the T8000, but is not far from it (600% vs 550%). They start to be available around 500€ (crankset, 11-38 cassette, derailleurs, brifters). If you take the 48/31 crank, the fastest speed will be as high as what you get with the T8000, and the slowest speed has a ratio of 0.8 (vs 0.74 for the T8000). With the 46/29 crank, the fastest speed will be marginally slower than the T8000, but slowest speed will almost match the T8000 (0.76).