A mate of mine bought a Mongoose Canaan Comp and is looking to mod' his bike so to be able to use both disc brakes with his right (and only) hand. He's done it with cantilevers in the past, but we've come unstuck with discs. Any idea on how this might be done?
Avid BB7 discs and a brake lever designed for a trike.
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mine are cheaper, £17 from tricyclesales.co.uk
Speak to TN on here. Her and her man ride for Team Bullheart, and he's only got one arm so uses the same system, although I think he uses hydraulics.
but where's the bling? Wont somebody think of the bling?!?!
does he want independent control of each brake on one lever for two calipers?
i'm sure you can get bmx levers which will be cheaper than pauls & better looking than ^ trike ones.
I think cable is the best bet as if you try and mod a hydralic you will need to increase the piston some how.
unless of course you use one of the cable to hydralic adaptors that have been seen around cyclocross for a bit
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Good stuff on here.
http://www.mtb-amputee.com/bikemodifications.htm#Mountain_Bike_Modifications_for_Arm_Amputees.
does he want independent control of each brake on one lever for two calipers?
We've assumed that control over both brakes would be out of the question. Have you seen a system able to control brakes independently?
While functional will do - bling good!
drop the good folks at hope a line
might be something they have an idea on
Good shout, Troutie!
IIRC, they have made a splitter for someone in the past.
I recall reading a magazine article where they went on a ride with one of the founder/owners of Hope - he was riding a bike and testing exactly this set up. From the photo it didn't look complicated - just a union that split the hydraulic pipe into two.
If you want to control the brakes independently you could look at a proportioning valve - we used them in race cars
[url= http://www.demon-tweeks.co.uk/Motorsport/Braking/Brake_Proportioning_Valves/Tilton_Lever_Type_Proportioning_Valve/1719/3478 ]Link here[/url]
aye. hydraulics should be very easy by just splitting the pipe. You might need a large volume piston to split (hope may be able to do that if you can't find a brake with a large volume) and yup a bias valve would be ideal to prevent lock ups.
How about a lever off a set of 4 pot brakes - eg hope or shimano saint along with calipers of a more normal 2 pot set up?
Leave the bias valve somewhere easy to access for tweaking it to the conditions.
Alternatively I am sure a way of controlling each independently could be done.
Similar to a car brake pedal maybe? Tee-piece the brake hoses together through a bias-valve and then tune to your heart's content.
Not the best control I admit but should be relatively easy to "build".
My husband uses Avid Elixirs with both levers stacked on the right bar. It looks crowded but it gives him control over both ends and he swears its easier than it looks.
Other hydraulic brakes will work but because you have to flip the left one over you need to have an inline reservoir otherwise you lose the pressure.
There's another chap on here rides with the same setup and he says it works for him too.
Plus I reckon this option fulfills the bling requirement too. 🙂
Actually - I have a couple of ideas for how to get more independent control. Will need to sketch them out really. Give me a shout (email in profile) if want to get stuck into getting something dedicated made instead of assembling something from existing parts and I will put pen to paper.
cound you change the hydraulic actuation from across the fingers to two finger levers (sorry for bad explanation and I think leverage etc could be an issue ) but imagine a bike with both brake levers on the same side and mounted vertically (so that both brake lever tips are pointing up and alinged with where two fingers go off the front of the bars in normal grip position) so that by pulling the appropriate finger towards you you would activate one or both brakes ?
In the recent article on Hope one of the guys was 2 running disks with a single lever. They may be after test pilots!
I have seen two hope discs run from one lever. You remove the bleed nipple from the front caliper then screw in a fitting and hose then run this to the rear caliper.
Some good ideas on that site.
Simplest solution seems to be:
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You can easily operate one lever with an index finger and the other with a middle finger.
This is neat:
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I guess the key has to be designing solutions which don't add to the riders workload.
You'd need a brake balance controller in there or you'd just lock the back all the time (with little braking on the front).
Or... you can get thumb actuated levers fro motorcycles. You may well be able to control a thumb lever and a regular lever at the same time. Maybe.
Did a few road races with a guy who had 2 STis mounted on the right hand drop handlebar.
If the end of the levers are close enough together, you can use a single finger on each lever, which cuts down the amount of faff to a simpleish how do I mount them question rather than splitters and such.
A lot of the polo guys are running front and rear off one lever, a lot are using those two cable out of one lever things and the rest seem to be using what i think are called travel adjusters but again they are cable only.
heres another lofi cable option
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A lot to think about here - thanks! I've assumed that having two levers on one side might be uncomfortable and perhaps too much strain when full anchors are required. I might be wrong, so I'll have him try this first.
I used to know a biker, predictably called 'bandit' who rode a motorbike with one arm. Controlled throttle, front brake and clutch with his right hand, and he used to be left handed.
andyl that bottom pic of yours is a thing of genius.
I had a go on a mountain trike and that used a T piece to run 2 avid calipers on each front wheel from one lever (v similar to many motorcycles). Maybe the guys there will be able to offer some advice. Google mountain trike.
"...is now riding one handed with some very cool modifications to his Mojo Mondraker – how does a moto gp thumb brake and steering damper sound?”
From here - http://dirt.mpora.com/uncategorized/tom-wheeler.html
Theres alot of good ideas up there,
I lost the use of my arm for over a year (nerve injury) and was riding s/s so only needed a brake mod for V's.
I pulled apart an old trigger gear shifter and removed the ratchet system and redundant lever, so it became a thumb operated brake. It worked really well and I've seen hydraulic versions for motorbikes around. Thats the route I'd choose.
Phill
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could you not mod of the shimano XT / XTR dual control levers? so instead of the hydraulic brake and cable gear change to hydraulic brake and cable brake? might be a good base to work from?
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then fit a separate shifter..
probably best though as a above to get one lever to operate two master cylinder via a balance bar to adjust bias or have a valve to limit pressure
Hope are releasing a mechanical to hydraulic convertor so you could use one of those dual pull cable things with it to get two whel braking - you;'d have to be careful on balance, though, I guess.
[url= http://ow.ly/i/fW1v/original ]http://ow.ly/i/fW1v/original[/url]