balrog687

Hello everyone!

My girlfriend had an accident and will take 1 year to (hopefully) recover her right hand/arm mobility. My goal is to allow her to safely ride her bike with her left hand.

Is there a 10-speed right-hand shifter compatible with Shimano Deore XT derailleur? (RD-M780 is the specific model).
My best option at the moment is a microshift thumb shifter mounted on the left side

I'm also looking for double cable brake lever recommendations. I've seen a lot of cheap options online, I want to replace Avid SD7 levers.

Thanks!!

groth

Not sure what kind of shifter she currently has. If it's a brifter - integrated brake and shifter - that will not work from the left hand side - the forces required would be in the wrong direction for the hand.

However, a bar end shifter would work just fine (you can get them indexed or friction). Just get the right hand shifter and install it in the left bar end, and route the cable and housing over to the down tube (sort of a mirror image of what you would do with the right hand bar end shifter) and after that the rest of the cabling would look the same as with the shifter on the right.

The above refer to road bars. I just looked at my girl friend's bike which has flat bars. Her shifters are separate from the brake mechanism and have two levers: one which you push on to move the derailleur to a bigger cog and one you click to release the derailleur to a smaller cog. It looks like you could just mount the right one on the left bar, but on the top of the bar instead of the bottom. This would allow pushing and clicking in the same direction.

Good luck!

csport

I know that Problem Solvers cable doubler exists, have never used it myself. An obvious disadvantage compared to a double cable lever is that should the cable at the lever break you lose both brakes.

VegasTriker

Shimano has a component comparability chart to show which components can be matched. https://productinfo.shimano.com/#/com

A good source of information for special needs cycling is Mark Powers at Power On Cycling in Newport, TN. The owner has specialized in working with disabled veterans and has a good reputation for finding solutions, https://www.poweroncycling.com/ The shop sells online as well as in person.

eddy m

A front brake only will stop as well as 2 brakes, and better than a double cable brake. There is no way to adjust the double cable that will not cause the rear wheel to skid under hard braking. Better to use the fornt only, and rig a second lever for the rear brake for redundancy.

em

PhilFo 

First off, good on you for thinking of her and if she wants to ride, helping her to do it.
So, what kind of bike does she ride now? The reason I ask is because an "aggressive" position on most mountain bikes or off road bikes will require her to hold herself up with both arms (bikes that Avid SD7s might be on). I learned this in 2010 when trying to get back on the bike after a major SLAP tear in my left shoulder. Surgery took care of the dislocation and torn soft tissue, but the 7 months of physical therapy mostly had me off my cyclocross bikes (and ended my collegiate racing career) and the only thing I could ride was a fully upright 1956 Rudge Sports.
So, it's not just the shifter and the brake, it's the center of gravity, the steering and handling that are all compromised when a rider loses use of one of their steering limbs. You may have to set her up with a riser stem, Northroad bars and a wider saddle for an upright position if she is unable to grasp and manipulate her current handlebar. Make sure the bar diameter is the old school MTB standard of 22.2mm, so the ancient parts you may be looking for actually fit.
Once you do that, since it's only temporary, get a left side Shimano Deore or Suntour XC thumbshifter and set it to friction then go ride.
Good luck to her in her recovery and let us know how this ends up.

VegasTriker

Do not rely upon the front brake only. Any longtime motorcycle rider will tell you that it is very dangerous to apply just the front brake even though it does about 60% of the braking. It's not much different for a bicycle. An awful lot of MTB riders have experienced what is called an Artie Johnson, a reference to the old TV program Laugh In. I know first hand having gone over the handlebars riding my MTB in the desert. You are way better off using the dual brake system even if the stopping power on the rear wheel isn't as good as the front. Here is a primer on the Science of [bicycle] Braking https://www.exploratorium.edu/cycling/brakes1.html
Balancing the braking between the front and rear tire is also important. Paul explained, "The most important things about stopping are that you want to stop quickly, in control, and not go over the handlebars. As I'm going along on the bicycle and I apply the brakes, my body has inertia and it still tends to go forward. That shifts my weight forward onto the front wheel. So, I do a lot of braking with the front wheel, but if I do too much braking with the front wheel, then I wind up going over the handlebars. So the idea of the braking the bicycle is to balance the braking between the front and the back to get the maximum braking."
It is not just an endo to worry about but skidding the front wheel as you try to both steer and stop. Then you are going to go down.

eddy m

A bicycle is not the same as a motorcycle. Bicycles have a shorter wheelbase and higher center of gravity, so the dynamic weight shift to the front wheel is much larger than with a motorcycle, so there's always the possibilty of braking yourself over the handlebars. The rear brake can't save you from that, and there is so much weight shift to the front that the rear cannot contribute much to maximum braking. Working boh brakes with one lever will only guarantee that the rear wheel will skid, which contributes no stopping power and risks a loss of control.
An independently controlled rear brake is useful for controlling speed on fast downhills, or for redundancy, but not much for maximum braking.

em

rickpaulos

electric shifting. Shimano Di2 system. You can put shift buttons anywhere.

I put Avid Speed Dial levers on some of my bikes. The ability to fine tune the brake cable pull ratio is pretty nice.

Not all brake cables are created equal. Some are thicker, some use stainless steel wires, etc. The longer cable run to the rear brake will have a bit more stretch. That can be a moderating factor for single lever control for 2 brakes. Like cars, the front brake should have a little more braking power. Canti lever brakes are easily ajdusted for cable pull so each brake can respond differently from the same lever. It's not that difficult to fine tune a single lever control for f/r brakes.

Leisesturm

The late, great, and too soon departed Sheldon Brown agreed. He has an entire article on front brake only stopping which I've read, but as someone (lazy) who often leaves rear brakes unconnected for months at a time, I wasn't one of those who needed convincing.

eddy m

FIFY
If you adjust the rear brake to engage under moderate braking, it will always skid the wheel under hard braking. If you adjust it so that it only engages for maximum braking, you won't notice much (if any) increase in stopping power. It's not that rear wheel braking is not worthwhile, it's that skidding a wheel at high speed is way more dangerous than the small loss of maximum braking power. At less than maximum braking, there's no loss of power at all without the rear brake.
We don't need to argue about this. It's easy to do the experiment. Roll from the top of a hill to a fixed point where you are doing 20 or 25 mph. Stop using both brakes. Then repeat with the front only, and again with the rear only. For more fun, try skidding the rear wheel deliberately while maximum braking from 30 mph or more. You'll see that I am right about this.

em

PhilFo 

It's absolutely possible with true cantilever brakes using a standard straddle wire (not the fixed length yoke.)

eddy m

It's easy to tune cantilever brakes to make more stopping power at the front than at the rear, but only by a fiixed proportion. The problem is that the rear wheel loses traction with increasing deceleration. In a panic stop, the rear has almost no traction, and will always skid even with minimal brake pressure. The loss of braking power without the rear brake is minimal, but a skidding wheel can be disastrous. If the front brake has enough power for maximum braking, it has enough power for everything else. Also, no one use cantilever brakes anymore, and they can't be fitted to most biikes, so there's that.
It's esay enough to do the experiment.

dm

bwilli88 

My daughter was born with a short arm on the left side, and we have her set up with a dual brake lever. It is a 36" wheeled MTB; with V brakes I have never gotten the rear wheel to skid. Try it.
I do not remember the brand, but it looks like a tektro MTB brake lever, and I got it from Ebay.
It has been posted on BF before.