PDA

View Full Version : Motor breaking on clutch lever - got questions



Hugues
07 June 2015, 1158
Hi guys,

I would like to add motor breaking using clutch lever. Currently I have only neutral braking setup on my Curtis controller. Questions:

- which parameters I need to change on Curtis controller to activate and set this motor brake ?
- what is the best way to link a potentiometer to a clutch lever. Or can we buy this kind of lever online ?

I would like to remove my rear mechanical brake and re-use the brake lever (set on left side of handle bar) for the motor brake.

Athlon
07 June 2015, 1648
mechanichal breaking is mandatory , having just the front breaking is too dangerous and you cannot control the bike in sharp turno and many other situation.

If the clutch is a wire type yust connect a normal pot at the end of the wire inside a waterproof box. On curtis there is the brake pot wires that take care of electronic brake , you can map it like the throttle in the brake menu

SplinterOz
07 June 2015, 1652
The solution I like best came from a guy called Danny Ripperton. He used a hydraulic clutch level and placed a pressure transducer on the output where the banjo would be. This gave a feel like a normal brake with braided lines very intuitive. Have a read here http://www.diyelectriccar.com/forums/showthread.php?t=138066

I do think you can make your own... just have to get the right transducer for your master cylinder.

Stevo
08 June 2015, 0730
mechanichal breaking is mandatory , having just the front breaking is too dangerous and you cannot control the bike in sharp turno and many other situation.

If the clutch is a wire type yust connect a normal pot at the end of the wire inside a waterproof box. On curtis there is the brake pot wires that take care of electronic brake , you can map it like the throttle in the brake menu

Fast Freddie Spencer used to remove his rear brake lever cause it got in the way of his big foot ;)
You don't need a rear brake at all. 90% of your braking is done with the front wheel (at least for me anyway) unless your riding offroad, then you need a rear brake absolutely, that's to swing the bike's rear sideways to enter into a turn.

Athlon
08 June 2015, 0859
rear brake is very useful when front brake is not working.

Some times ago an asshole stole my front caliper , I was in hurry and late so after work I just tok the bike without doing a bike check , from my work you cant take the highway almost straight so I found out about the missing front brake only when was time to get out of the highway ( my home exit is a sharp turn ) .... right now I'm still alive thnks to the rear brake.

Stevo
08 June 2015, 0902
Good story with a happy ending Athlon...
Thieves suck:mad:

podolefsky
08 June 2015, 1209
rear brake is very useful when front brake is not working.

EXACTLY

I have the clutch lever > regen brake setup (see this page (http://elmoto.net/tell-us-about-your-project/874-93-gsx-conversion-16.html)). I like Ripperton's solution better since it gives a more realistic brake feel, but mine works fine. It's pretty easy to lock up the rear - you really have to finesse it.

I would never drop the mechanical rear brake. #1 reason safety. Also, the regen brake has some speed dependence, not quite as predictable.

Rear brake is also useful for starting on hills. The regen brake won't do anything at a stop.

Electro Flyers
08 June 2015, 1217
You don't need a rear brake at all.

So, you've pulled the rear brakes off of your bikes? What happens if the front brakes fail? Or, if you're on a hill(thank you, Noah); or your caliper gets stolen( that's a good one, Athlon!)

Stevo
08 June 2015, 1929
I use my rear brakes!
Noah...
How does the clutch lever/motor brake feel? If its just a banjo bolt hydraulic pressure sensor then it could be used on the rear brake master as well.
But can you actually feel the control with hand or foot pressure ?

podolefsky
08 June 2015, 2000
It feels like a light spring. It's just a cable lever going to a PB-6 pot box. I can pull it all the way to the bar without much effort. It took some practice, now I'm used to it and I can apply just enough in different situations. I pretty much only use it at stop lights or straight downhills. Anything that needs more finesse I stick with mechanicals.

Electro Flyers
08 June 2015, 2051
I use my rear brakes!


Ok, so you have rear brakes. Why are you telling people that "You don't need a rear brake at all"? It seems dangerous and irresponsible to make this kind of assertion. You seem very knowledgeable, but if your not following your own advice, it's very difficult to believe what you say.

Stevo
08 June 2015, 2234
Oh sorry its my humor. I was merely stating that you don't need rear brakes. Flat trackers and speedway racers have no brakes at all.
I'm a dirt biker and street rider for many years, since age 15.

Podbuilder
09 June 2015, 0208
Just thinking out loud as I've no idea if this would work, but put a throttle on the left handle bar so you'd need to rotate it backward to activate the regen braking and maybe a thumb button stitch on the right handle bar as a safety to close the circuit . I might try this on mine.

Stevo
09 June 2015, 0631
I know Lightning has it controlled by the throttle position sensor. Is there a way to do that? That makes the most sense to me.

Electro Flyers
09 June 2015, 0744
Stevo, I have to talk to people about EVs after they've read blanket (ill informed?) statements like this one. And, it's not funny nor humorous having to try to set them straight on issues of safety or EV design.

Here's a all-in-one throttle/regen control I've mentioned before:http://www.freeenergystore.com/evhubmotors.html (item 15). I've not had a chance to try one. Has anyone on the forum tried one? They're made for a bicycle system, but might work on a MC.

Nuts & Volts
09 June 2015, 0900
I currently have a left hand lever with built-in master cylinder. This is connected to a pressure transducer (150psi) which then sends a 5V signal to my controller. I want a 300psi unit so that I can pull a bit harder to feel more connected to the braking and so that I dont risk damaging the one I have.

It works great and I can program it to give really great feel. I can also program the max regen torque so that it is impossible to lock in normal riding conditions. To me it is safer/more confidence inspiring than the mechanical rear brake.

I two have dreamed about removing the mechanical rear brake (would save like 7lbs). I understand the redundancy risk. I have never had the controller shut off and have never had the front brakes had a problem in 5000miles of riding. That's my data point. With dual front rotors on my bike I think you could run independent master cylinders on one lever to each front caliper. This gives two independent mechanical and one electrical braking method. I would feel comfortable removing the rear brake in that situation.

Lex
09 June 2015, 1104
Would using two hub motors one for the front wheel and one for the back each having their own separate regenerative capabilities be a possibility for braking instead of using mechanical?

Hugues
09 June 2015, 1131
Would using two hub motors one for the front wheel and one for the back each having their own separate regenerative capabilities be a possibility for braking instead of using mechanical?

Not possible here in Switzerland, one mechanical brake is mandatory (front or rear).

I agree that from a safety point of view, no mechanical brake at the back is questionable. And also from a low-speed riding confort point of view, i often like to hold the bike with the rear brake, would be difficult to achieve the same with motor brake only, i think.

I do realise again while riding today, that my "neutral braking" set-up has some kind of graduation, it's not ON or OFF only, it can also be in-between. I mean by neutral braking, on Curtis, when you release the throttle, the motor braking force is somewhat proportional to the amount of roll back of the throttle. I'm pretty sure about this, if i roll back a bit, the negative amps on my display go into the 20's amps, if i roll back completely, i can read around 80's negative amps. I have my neutral braking parameter on Curtis set to 40%. Anyone else uses this type of motor braking ? Do you also feel a certain graduation when rolling back ?

I'm not sure i would feel confortable with a brake lever connected to a pot only, i think i prefer to have resistance in the lever. Maybe a pressure transducer would give this. But if i cannot get rid of the rear mechanical brake, then i think it's not worth the trouble for me, i'll stay with my throttle roll back motor brake. In normal riding conditions, i almost never use my mechanical brakes, only at low speed or coming to a complete stop.

But thanks for all the input.

podolefsky
09 June 2015, 1259
Would using two hub motors one for the front wheel and one for the back each having their own separate regenerative capabilities be a possibility for braking instead of using mechanical?

You would still need mechanical because regen will only slow you down if you're moving, it won't hold you at a stop.

podolefsky
09 June 2015, 1334
A few things to consider:

-Depending on your system, regen might not work for the first few miles until your pack has discharged enough. Mine always seems to work right out the door, but I know this isn't always the case (might have to do with cell chemistry and rest voltage).


Just to add to the discussion - the rear brake isn't just a backup in case the fronts fail (although for me that is #1, even if it adds a few lb).


Three things you can do with your rear brakes, either mechanical or regen:

-Control the bike if you have a front blowout.

-Apply more braking force (unless the rear wheel is actually off the ground). This is especially true on cruisers that are more weight biased to the rear.

-Settle the suspension - useful entering turns, especially downhill. (Don't take my word for it https://www.youtube.com/watch?v=MddguBZRieQ)


Three things you can't do with regen:

-Holding the rear brake on a hill. You can learn to start on a hill with just the front, but it's a lot easier with the rear.

-Holding yourself in place at a stop while you sit up and stretch. (For real, I do it all the time.)

-Consistently go back and forth between electric and gas bikes (may not apply to all). The one place I want my reflexes to be consistent is braking, so I try to keep my braking technique the same.

Stevo
10 June 2015, 1006
A few things to consider:
-Settle the suspension - useful entering turns, especially downhill. (Don't take my word for it https://www.youtube.com/watch?v=MddguBZRieQ)
.

That was cool. Did you catch the part about removing brake pad material back in the day?
I've had guys crash right in front of me going into turns too hot on their rear brakes. Yes...proper technique is required.
As far as front brake failure... I've logged probably over 100000 miles in 35+ years of riding over 15 different motorcycles ( dirt and street) and NEVER
had a front brake failure. NOT once. I think that's pretty decent odds. That doesn't mean it can't happen. I bleed my own brakes and have always
done my own brake pad changes. Here's a good video about how to properly "bed" your new brakes: https://www.youtube.com/watch?v=Pi4BAuMjpbE

On a street bike, 90% or more of your stopping ability is in the front brakes. Yes there are times feathering your rear brake will help in certain situations. These are advanced racing techniques.
When it comes to rear brakes, go gently! Keep in mind this is about street bikes, where you have lots of traction between rubber and pavement.
BUT on a dirt bike, where your constantly sliding, the rear brakes are used way way more. As a matter of fact... I highly recommend riding dirt bikes to complement your street riding... it will make you a better rider on the street. You will learn how to handle your street bike when you lose traction on the pavement.

Hugues
10 June 2015, 1038
..

-Apply more braking force (unless the rear wheel is actually off the ground). This is especially true on cruisers that are more weight biased to the rear.

-Settle the suspension - useful entering turns, especially downhill. (Don't take my word for it https://www.youtube.com/watch?v=MddguBZRieQ)
..

Interesting.

Come to think of it, i have my rear mechanical brake on my left handle bar, i think i have more "finesse" controlling it this way than if i had it under my foot. So another reason to keep my current set-up.

And thinking of my commute ride today, 40 km, i think i did not touch my front mechanical brake, maybe once max. 90% of braking done with engine (so rear braking), and using the rear mechanical brake to hold the bike in place when stopped or in a tight turn at low speed. Of course in an emergency stop, my rear mechanical brake can quickly lock the rear tire if i pull too much, happened to me once or twice.