Linked Hydraulic Brakes

Pegaso650

Hi,

I'm new to this site, trolled through the search function but couldn't get an answer. So -

Does anyone known of a company/manufacturer that does linked hydraulic brakes for MTB's?
Separate bias valve for front to rear?
Option to join hydraulic lines for 1 lever to operate front and rear brakes?

Reason I'm asking -

In February this year I suffered a fairly large stroke. It's left me with reduced control of my right hand/arm. I'm back on the bike now, using the rear brake only. Gear function has been relocated to the right side of the bars. I know a thumb brake is possible not unlike motogp, but I'm very restricted on space.

Any ideas welcomed.

Many thanks

Jon.

rockmonkeysc

I have seen someone with one arm who had botm lever on one side but not linked.
Try speaking to Hope, they might be able to help.

nicklouse

have a read viewtopic.php?f=40073&t=12812329

Pegaso650

nicklouse wrote:

have a read viewtopic.php?f=40073&t=12812329

I like that!

Off to the garage I go!

Many thanks

Jon

nicklouse

Keep us updated with the mods.

bikaholic

There is another method for operating two calipers using a single lever and that is to daisy-chain the two calipers.

Specifically, connect the lever to the first caliper as normal then connect the second caliper via the bleed port on the first caliper.

So, you will need calipers with M6 or M8 threaded bleed screws because hose end fittings using these standard threadings are easily obtainable.

And, it will work because I have tried it myself back in 2001 after getting the idea from servicing a Magura HS33 hydraulic rim brake.

nicklouse

bikaholic wrote:

There is another method for operating two calipers using a single lever and that is to daisy-chain the two calipers.

Specifically, connect the lever to the first caliper as normal then connect the second caliper via the bleed port on the first caliper.

So, you will need calipers with M6 or M8 threaded bleed screws because hose end fittings using these standard threadings are easily obtainable.

And, it will work because I have tried it myself back in 2001 after getting the idea from servicing a Magura HS33 hydraulic rim brake.

But with that you have no means to control the force applied by each brake.

What the above does is allow differing forces to be applied to the brakes via the reach adjuster.

Just like a race car.

Daisy chaining results in one end locking up first. Unless you put a pressue reducing valve inline to the end that requires less force. As you can do on a race car with a single line brake system.

tangled_metal

There was a programme on TV about this guy trying to break the soap box racer speed record. He had one pedal to operate disc brakes on 4 wheels with a valve to adjust front/ rear braking force. He got it from Hope. Perhaps if the above ideas don't work then contact them.

bikaholic

nicklouse wrote:

... Daisy chaining results in one end locking up first. Unless you put a pressue reducing valve inline to the end that requires less force. As you can do on a race car with a single line brake system.

Yes, this I know (although the pressure valve is not needed since the hydraulic system is too small to be significantly affected by caliper imbalance), but independent control of each caliper was not in the OP's request. That leaves the door open for other ideas - of which I have a few more.

jimothy78

Surely the bigger problem with this "Daisy chaining" idea is that you're running two callipers from one lever. That means that to close the gap between the pads and rotors, you're going to need twice the fluid flow, hence twice the lever travel before you reach the bite point. Obviously, a lot depends on make and model, but I reckon that if you doubled the free stroke on my Deore brakes, the levers would be hitting the bars before they really started working.

Also, a leak or damage to any part of the system is going to render the bike entirely brake-less. Two levers, two hoses would mean that in the event of a fault, you've still got one working brake to do something with.

Pegaso650

Day later than I wanted, due mainly to having a day in hospital, some pictures.

After some tedious work, I managed to get both brakes and shifters in the right place.
Working one handed is a pain to say to least!




I'll try it like this for a few longer rides - ideally I'll get the use of my right hand back at some point in the future.

Any comments/ideas welcomed

Jon