Single lever, dual caliper brakes for trike

So here is the thing… We have a cargo bike in the family. It’s a large, three wheeled monster, that is infinitely useful for hauling kids, groceries, beer, and whatnot around. It’s called a Christiania Bike, and it has a motor in the back wheel. It weighs about 30 kilos in itself, and the allowed system weight is around 250 kilos. I do not use it very often, but the missus uses it almost every day. It has Bengal hydraulic brakes fitted on all wheels, and the two front wheels use the same brake lever. The hose from the lever goes to a splitter, which makes sure that the front brakes move in sync. Additionally, the lever is fitted with a lock, that makes it work like a handbrake for parking.

The problem is, that these brakes absolutely sucks. They do not work. They are weak, no modulation, the brake pads are tiny, and they need to be changed very often. The size of the pads is quite uncommon, which means that they are quite hard to come by, and never cheap. The only equivalent I could find are the pads used in Hayes Sole/ MX calipers. The brakes always rub the disks, no matter how carefully or often I align them. I don’t mind the brakes squealing now and then, but the wife hates it… and then she makes sure that I know her feelings about brake squeal. Over and over until I align it again and we both get a few days of peace and quiet.

The back brake is not the main problem, I could take off the damn Bengals, throw them as far away as possible, and fit a Shimano Saint or brake system… which would probably cure my problem in the rear. But what about in the front? I have been trying to find a single lever, dual caliper system that would work, but apart from a Hope system that is eyewateringly expenisive, and a Magura system that seem to have been discontinued, not much turns up. I contemplated just exchanging the Bengal calipers for another set, but Bengals use DOT fluid, and I have no experience what so ever with brakes other than Shimano and Magura.

Any suggestions as to where I should concentrate my search? Has anyone built up a trike with hydraulic brakes recently?

I have had my eye on a Tektro Auriga Twin to upgrade my KMX trike if I ever manage to get a reliable chain idler on it.

I will follow with interest, though, in case there are any magic setups I could bodge together.

When you say hope lever, do you mean the dual lever on a single clamp? That’s meant for one armed riders to have independent control of 2 brakes.

Don’t you just need to have a splitter in the hose which turn goes to each front caliper? I’m guessing you don’t want to be able to brake an individual wheel on it’s own.

Motorbikes mostly have 2 front calipers and a lot of them just split the brake feed to the calipers. Works fine for them! Or, a longer dual banjo bolt with 2 separate hoses from the master cylinder to each caliper.

Edit: hope do a dual caliper single lever system, it’s basically just a normal system with a splitter.

https://www.hopetech.com/products/brakes/cross-country/tech-3-x2-uno/

Last time I looked for a customer it was Hope or Magura. The Hope setup was expensive, but worked well.

You can also build your own setups, just do the calculations for surface area of the master cylinder piston, caliper pistons and stroke. If you stay everything dot or mineral you can mix and match levers and calipers as long as the piston ratio and stroke is ok, you will need to work out fittings etc.

I’m pretty sure a brake or hydraulic specialist would be able to supply a splitter and hoses for any hydraulic brakes you wanted. It’s a pretty basic thing really.

https://www.bike-components.de/en/Magura/T-Splitter-for-Brake-Hoses-p60538/

Assuming it has standard brake mounts, some Deore 4-pots with 8″ rotors on the front would be an obvious place to start.

it has a motor in the back wheel

I’m surprised nobody’s told you that’s cheating yet.

Hope use a Tech 3 lever and 2 X2 calipers

You can do it with a T piece.
My wife’s Mountain Trike has a single Avid lever going to a T serving a pair or calipers.

Some good suggestions here. Upgrading the rotors are not an option, the brake mounts are fixed and bodging them would be a bit risky.

Of course the motor is cheating, but a bike with an adult, up to four kids and gear is bloody heavy. This is the third Christiania Bike we have, the two first were without motors and had five speed internal gears and roller brakes. In fact, in my household it is always known as “Snydecyklen”, which is Danish for “The Cheater Bike”.

I will take a look at different calipers. I already have the hardware on the bike, so the splitter is sorted. Which calipers use DOT fluid these days? Hayes and SRAM, I presume?

The likely issue with a splitter is that the reservoir won’t be big enough to cope with the pad wear of both calipers. The reservoir on Shimano brakes is barely big enough for one caliper, so you’ll end up topping up the fluid or throwing away half used pads. If you could find a lever with a more generous reservoir it’d probably work.

You’ll also end up with a lot of lever travel but probably usable.

I would like to continue using the Bengal lever, simply because of the built in parking brake option, which is quite rare. It has also been built for dual calipers, and has a large reservoir.

One of our pre-lockdown Wed riders is a para-olympic Gold medal cyclist, BC modded his bike so he has both disc brakes on one lever – Shimano IIRC.

If you could find a lever with a more generous reservoir it’d probably work.

Motorbike lever with Avid calipers?

Edit: The existing lever with Avid calipers would probably be a better option.

Yeah – SRAM/Avid are DOT. You’ll need to check the caliper piston sizes. If the current ones use small pads, they may have small pistons.

You can also build your own setups, just do the calculations for surface area of the master cylinder piston, caliper pistons and stroke. If you stay everything dot or mineral you can mix and match levers and calipers as long as the piston ratio and stroke is ok, you will need to work out fittings etc.

I don’t think being quite that exact is important. most manufacturers only make a single master cylinder to drive everything from their XC brake to the biggest 4-pots (e.g. XT, Xt-4pots and saint all used the same lever until they updated the XT one.

Assuming it has standard brake mounts, some Deore 4-pots with 8″ rotors on the front would be an obvious place to start.

I’d go with big rotors and small calipers, means less fluid is needed. Despite what I said above I’d not push my luck with 8 pistons of a single master cylinder!

Some good suggestions here. Upgrading the rotors are not an option, the brake mounts are fixed and bodging them would be a bit risky.

What’s fixed about them? Can’t you just fit adapters like normal? Assuming they’re IS or post mount I’d just get the biggest rotors that will physically fit, you can get 220/223mm rotors now! The easiest solution would be just to do that rather than mess with the brakes themselves.

That to me looks like a standard post mount caliper. Just find a rotor 20mm bigger, and get some +20 adapters.

most manufacturers only make a single master cylinder to drive everything from their XC brake to the biggest 4-pots (e.g. XT, Xt-4pots and saint all used the same lever

Yes, but they’re all basically the same ratio aren’t they? The 2 pots are 22mm, and XT 4 pot is 15mm + 17mm which is only 6% more area.

Hope V4 calipers and 220mm rotors. Accept nothing less 😀

I think that I maybe didn’t explain the problem with fitting other rotors. First of all, the setup on the picture is not the one thats on my bike. The bike pictured looks like one of the bikes they make for commercial use, like bike taxis, handicap transport, sales carts, and so on. The one on my bike is more flimsy, and I think that is one of the reasons the brakes squeal. There is already one special adapter fitted, and I think that it is a bad idea to put an adapter on top of an adapter. I could be done, if I really wanted to. That will be my last resort.

My main gripe is not the lack of braking power. It is the fact that I have to align and adjust the bloody things almost daily, in order to make them shut up. I had hoped that some calipers from another company would be more forgiving in their setup, giving me slighly more leeway before they start making noise.

Hmmm, have you tried different pad compounds or even disks?

I just swapped from sram centerline to shimano to cure a squeel. I can now almost get the front tyre to lock up on tarmac without a squeel which is much nicer than the howling SRAM rotors.

are you sure the squealing is coming from the caliper, not the rotor vibrating or some other part?

I’d bodge on a single-sided brake from another bike and ride it round to see if the squeal is cured. if not you’ve just saved a load of effort..

I’d be weary of trying to run 2 calipers off one lever. even if the reservoir is big enough, I doubt the master cylinder will push enough fluid to effectively actuate both calipers

I doubt the master cylinder will push enough fluid to effectively actuate both calipers

If they’re properly bled and the pistons not stuck in the calipers, this shouldn’t be a problem. The pistons only move a tiny amount when you apply the brakes so you’re not actually pumping much fluid. As above, the problem will be when the pads wear and there isn’t enough fluid in the reservoir to compensate.

There is no doubt that single lever dual caliper setups can work. They are used in many places, especially on trikes and bikes used by people with one arm missing, or weaker than the other.

It’s just that the calipers that Bengal uses are made of cheese, and with a very small gap between pads, which means that they need to be aligned to within a micron with the disk in order to stop making rubbing or squealing noises.

Additionally, it really bothers me that the pads are quite unusual, which means that aftermarket options ar very limited and expensive.

There are some good suggestions in this thread, and I will look into fitting other calipers.

If you’re intend on keeping the same rotors and lever then you need a dot fluid caliper. One of the cheapest big powerful caliper options is the one on the Sram Guide RE (not the same caliper on the r / rs / rsc). It’s the old Code DH brake caliper and has a lot of power and easily brake pad availability.

You could also look for the old Code brakes for the same caliper.

The new Codes have a better caliper still – but they’re a lot more money.