Basic tadpole trike question - brakes

DIscuss anything relating to non-standard cycles and their equipment.
belgiangoth
Posts: 1394
Joined: 29 Mar 2007, 4:10pm

Basic tadpole trike question - brakes

Postby belgiangoth » 21 Jul 2020, 4:34pm

My understanding is that with tadpole trikes the rear brake (if any) is purely a parking brake and the front brakes are where it's at.
So, are both brakes actuated by the same lever? If so what happens when you need to signal with that hand, or if the cable snaps? If you have a different brake for each wheel, won't that give you brake steer?
If I had a baby elephant, it would point out that there is no evidence for planing. Then it would eat all my bananas.

User avatar
[XAP]Bob
Posts: 17496
Joined: 26 Sep 2008, 4:12pm

Re: Basic tadpole trike question - brakes

Postby [XAP]Bob » 21 Jul 2020, 4:42pm

Depends on the trike...

Most trikes have independent L/R braking, but some share a lever via some mechanism. Tigerbitten for example just uses one lever for obvious (if you've met him) reasons.

The KMX K3 I have has dual band brakes with a single lever (and a v brake at the back for handbrake turns)

The ICE steering geometry is such that you can (though I wouldn't recommend it) disconnect one tracking rod and brake with the other wheel.

I've never had an issue with steering, braking, and signalling at the same time - though obviously with two brakes you do get better control (I instinctively brake more on the outside (loaded) wheel in a corner for instance)
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.

belgiangoth
Posts: 1394
Joined: 29 Mar 2007, 4:10pm

Re: Basic tadpole trike question - brakes

Postby belgiangoth » 21 Jul 2020, 4:50pm

[XAP]Bob wrote:Tigerbitten for example just uses one lever for obvious (if you've met him) reasons.


Yeah, I always thought it was just an internet handle.
If I had a baby elephant, it would point out that there is no evidence for planing. Then it would eat all my bananas.

n0ct0
Posts: 22
Joined: 27 Apr 2020, 2:11pm

Re: Basic tadpole trike question - brakes

Postby n0ct0 » 21 Jul 2020, 9:56pm

You can steer with the brakes on HP trikes. Quite handy, but also a bit weird.

User avatar
Tigerbiten
Posts: 2066
Joined: 29 Jun 2009, 6:49am

Re: Basic tadpole trike question - brakes

Postby Tigerbiten » 21 Jul 2020, 10:51pm

It depends on the steering geometry on how much brake steer you suffer.
If the trike is well designed then the brake steer is predictable and controllable.
I've done that after disconnecting a front brake due to a cable failure while on tour.
I just have to pull the single brake on more smoothly vs twin front brakes.

You can use a rear brake for stopping on a tadpole trike but it does take longer and can be much more iffy if the road/track is slippery.
I've done that a couple of times after a total front brake failure.

With only one hand, if I need to brake and indicate at the same time (normally into downhill junctions) then I either use my back wheel drag brake or I use my leg to keep holding the front brakes on.

Luck ......... :D

belgiangoth
Posts: 1394
Joined: 29 Mar 2007, 4:10pm

Re: Basic tadpole trike question - brakes

Postby belgiangoth » 21 Jul 2020, 11:38pm

I assume you can also compensate for it though - e.g. steer right but brake left to balance out.
If I had a baby elephant, it would point out that there is no evidence for planing. Then it would eat all my bananas.

User avatar
[XAP]Bob
Posts: 17496
Joined: 26 Sep 2008, 4:12pm

Re: Basic tadpole trike question - brakes

Postby [XAP]Bob » 22 Jul 2020, 12:16am

Yes, happens very naturally.

But geometry is king. You can’t just slam on one brake, lock up and expect to be going in a straight line. But progressive braking shouldn’t send you off course.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.

OldBloke
Posts: 117
Joined: 15 Jul 2014, 3:34am

Re: Basic tadpole trike question - brakes

Postby OldBloke » 22 Jul 2020, 12:47am

Yes, separate L and R brakes on mine.

My HPV Gekko has more a bit more brake steer than my Performer Trike-F. I got used to it pretty quickly and learned to compensate.

I've ridden a friend's Catrike 700. I wasn't aware of any brake steer with it. Greenspeed also don't seem to suffer from brake steer.

OB

User avatar
Tigerbiten
Posts: 2066
Joined: 29 Jun 2009, 6:49am

Re: Basic tadpole trike question - brakes

Postby Tigerbiten » 22 Jul 2020, 5:14am

The other thing good/bad geometry can alter is the amount of bump and camber steer you suffer.
If one front wheel hits a lump/hole/soft patch, especially at speed, how badly do you deviate off your line.
This is similar to camber steer, how fast do you dive for the ditch when you lean to counteract the slope of the camber.

Luck ....... :D

User avatar
yakdiver
Posts: 1217
Joined: 12 Jul 2007, 2:54pm
Location: North Baddesley Hampshire

Re: Basic tadpole trike question - brakes

Postby yakdiver » 22 Jul 2020, 7:39am

12 volt indicators and yes motorist do see them.
Alias Numbnuts

User avatar
squeaker
Posts: 3649
Joined: 12 Jan 2007, 11:43pm
Location: Sussex

Re: Basic tadpole trike question - brakes

Postby squeaker » 22 Jul 2020, 9:43am

ICE trikes = very little (if any) brake steer; WAW velomobile = slight brake steer (both have 2 independent brake levers). IME far less of an issue than having to use the rear brake only when signaling right on a bicycle ;)
"42"

belgiangoth
Posts: 1394
Joined: 29 Mar 2007, 4:10pm

Re: Basic tadpole trike question - brakes

Postby belgiangoth » 22 Jul 2020, 11:26am

My standard upright is a fixed gear, so I can leg brake when indicating. I take it fixed gear is less convenient with laidbacks.

On my upright cargo trike there's brake steer and camber steer and all. It handles much better with a heavy load (and a little practice). It has one brake lever for both front brakes so I reckon it's just loosening something along the brake cable to sort out the brake steer, but ~15 years of fixed have made me mechanically stunted so I need to re-learn everything from scratch (what are these "disk" brakes of which you speak).
If I had a baby elephant, it would point out that there is no evidence for planing. Then it would eat all my bananas.

User avatar
[XAP]Bob
Posts: 17496
Joined: 26 Sep 2008, 4:12pm

Re: Basic tadpole trike question - brakes

Postby [XAP]Bob » 22 Jul 2020, 11:40am

Single lever brake systems need to have something to balance them, whether that's mechanically automated or regular maintenance.

Of course you get used to whatever brake steer your particular vehicle has.

Shouldn't be too hard to get the brakes working together... There are normally fine adjustments possible using little knurled doodads at the brake lever.


I should also add, in further reply to the original question, I can easily lift the rear wheel, even when the trike is loaded... I can't always lift it in the wet, but I can certainly unload it to a very significant extent.
If the rear wheel completely loses traction (or even contact) with the ground then you only have differential braking for steering.
Fortunately that situation is usually very short lived. though if you were relying on the rear wheel brake you could easily end up doing handbrake turns (like on the kmx) which, at speed, would certainly be able to flip you sideways.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.

User avatar
Tigerbiten
Posts: 2066
Joined: 29 Jun 2009, 6:49am

Re: Basic tadpole trike question - brakes

Postby Tigerbiten » 22 Jul 2020, 1:29pm

The twin cable brakes off one lever are a bit tricky to set up.
I set one up so the lever was in the correct position at max brakes.
Then dialed the second one in with the barrel adjuster.
It didn't matter that much if one started slightly before the other, but that could be adjusted out with care.
I set then up so at almost max braking both stopped me by the same amount, that stopped any chance of brake steer if I needed to grab a handful of brakes.
My twin hydraulics brakes off one lever are self balancing, so very easy to set up.

With only one hand, I can bunny hop the back end if the brakes are new.
Once they're worn a bit and lost a little stopping power I lose that ability.

But the brakes on a tadpole trike may be a bit of a minefield.
The 1983 regs state:- Both fronts off one lever and the back off another one.
And I'm not sure if there's a newer reg which adds the provision for independent front brakes.
It may just be a case of "don't crash" with independent fronts ........ :roll:

Luck ........... :D

Shreds
Posts: 44
Joined: 19 Dec 2010, 4:43am

Re: Basic tadpole trike question - brakes

Postby Shreds » 22 Jul 2020, 2:07pm

Tigerbiten wrote:The 1983 regs state:- Both fronts off one lever and the back off another one.
And I'm not sure if there's a newer reg which adds the provision for independent front brakes.


Back in '83 the Regs would have had traditional trikes in mind, or ice cream carts. Mike Burrows obviously pioneering the tadpole Windcheetah, was probably beyond the legislators comprehension at that time.