splice hydraulic lines.

Y

ynot

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Does anyone know of a kit that will allow me to splice the hydraulic lines from a motorcycle brake lever, to the hydraulic lines of a pair of ebike calipers. The goal is one lever actuating the calipers on the front wheels of my tadpole trike.
Am hoping that a kit of parts would have the right size inserts for each of the lines and a coupling to join them.
The inner hdpe line of the bicycle calipers fits snugly into the tube of the larger Motorbike lever. Am hoping to make a good working splice, have a splice which I made, and if there is no kit available will test my splices thoroughly before mounting on the trike. The brake lever has calibration so that I can adjust the volume of oil sent to the calipers thus avoiding an over the handlebars gymnastic exercise.
 
There will not be a kit for that, because it's a hokey idea that won't fly commercially, at least anywhere there's product liability.

Most bicycle hydraulic discs use mineral oil based fluid, similar to automatic transmission fluid. Motorcycle hydraulic brakes use glycol based fluid ("DOT fluid"). You can combine incompatible parts by using silicone fluid (DOT 5, not DOT 5.1). But integrating very different hose diameters and fitting sizes/styles won't be easy or reliable.

There are kits of bicycle discs designed to do what you are doing. Tektro Auriga Twin and Magura Big Twin are the ones I'm familiar with.

http://www.tektro.com/mobile/products.php?p=31

https://www.venhillusa.com/big-twin-brake-system-less-discs-0134117.html

You could use the lever from either of these systems to operate two of pretty much any other bicycle calipers that use mineral oil.

Main Street Pedicabs uses a Magura Big Twin lever (for mineral oil) to actuate a weird racing kart rear caliper (for glycol), using DOT 5 silicone fluid. Those brakes feel pretty gross and leak like that's their job. But it's the setup they have used for decades now.

If you don't want to deal with a leaky, self-contaminating mess, you can get a dual cable brake lever and use two Avid BB7 calipers.
 
Thanks for the tip Chalo, I figured if anyone on the site had a solution it would likely be you.
 
KTM motorcycle has a mineral oil clutch activation system ... a left side lever.
Mineral oil in a DOT brake system works fine with no leaks with the caveat that mineral oil will boil at high temps.
For several applications, I've used motorcycle front brake masters (right side lever) pushing 2 bicycle slaves for perfect no leak results.
The first couple tries it did take a custom modified fitting to blend the different size hoses.
Somewhere in the internet I found an adapter fitting that reduces the motorcycle master down to a bicycle hose.

DOT fluid in a mineral system will swell the seals ... unless DOT silicone fluid is used.
Silicone fluid won't swell either seal type.

The main thing your looking for is an increase in piston size. 2 ~ 3mm usually does it.
 
PaPaSteve said:
KTM motorcycle has a mineral oil clutch activation system ... a left side lever.
Mineral oil in a DOT brake system works fine with no leaks with the caveat that mineral oil will boil at high temps.
For several applications, I've used motorcycle front brake masters (right side lever) pushing 2 bicycle slaves for perfect no leak results.
The first couple tries it did take a custom modified fitting to blend the different size hoses.
Somewhere in the internet I found an adapter fitting that reduces the motorcycle master down to a bicycle hose.

DOT fluid in a mineral system will swell the seals ... unless DOT silicone fluid is used.
Silicone fluid won't swell either seal type.

The main thing your looking for is an increase in piston size. 2 ~ 3mm usually does it.
Click to expand...

The motorbike lever that I have was given to me by a dear Friend who owns a motorcycle repair shop in Mazatlan. It has a single hose going to a splitter, If I could find banjo's to fit that splitter, and fit the calipers it would be the best solution, the aforementioned lever fits the trike much better than any other I have tried.
Have a lathe and mill so could make banjo's but do not have the capability of cutting threads to connect the caliper hoses. wonder if it would be possible to swage the caliper hoses to the motorbike banjo's?
 
What brand are the slaves ?
Hose fitting thread type into the slave ?
Master still have the complete lines down to the banjo's fittings that would attach to the calipers ?
 
PaPaSteve said:
"What brand are the slaves ?"
NOUJIU Mountain Bike Hydraulic Disc Brakes Set, ......... Was buying for low cost.

"Hose fitting thread type into the slave ?"

Have not undone one, but they are not banjo's
"Master still have the complete lines down to the banjo's fittings that would attach to the calipers ?"

Have
Brake lever hose to splitter with banjo's, complete, hoses from splitter to original motorbike calipers, both cut between splitter and caliper,
Ebike calipers with brake levers, both lines cut.
One of the banjo's on MB caliper cut on the metal pipe portion.
Click to expand...

filled the MB lever with mineral oil, it appears to work well.
Hope I have not done too much damage by cutting the lines, should have come here first, but lines are not too expensive.
 
My usual approach is to figure out an adaption from the motorcycle master to the bicycle hose size then use the Magura "Tee" fitting to split the line.
TIG welding two fittings together is one of my common hacks.

Maybe the motorcycle banjo can be threaded for this fitting ?

https://www.ebay.com/itm/224983067475?chn=ps&_trkparms=ispr%3D1&amdata=enc%3A1DCpB1FoIS92s1VMOOaZ8KQ38&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=224983067475&targetid=&device=c&mktype=pla&googleloc=9033039&poi=&campaignid=17597089569&mkgroupid=&rlsatarget=&abcId=9300988&merchantid=582773442&gclid=CjwKCAjwpKyYBhB7EiwAU2Hn2VJ3KGngfkWwUMn6DWkSXr-6kr_Ksf-v4bfAXkU5NrB1lv8M3EXI-RoCuiQQAvD_BwE

To ease the fluid bleeding make the whole assembly easy to remove from the vehicle.
Much easier to wiggle any air bubbles to the top when it's off the bike.

When there's a will there's a way.
You'll figure it out ...
 
HMM! Brazing, damn I sold my jewelry making oxy propane mini torch when I retired.
Could possibly cut a thread onto the MB banjos and make an adaptor.
Great ideas, thank you for making think of new solutions.
 
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