HELP - Newbie - Cadence Sensor installation issue.

[Firebird]

Hi guys,

A little history.

I am new to e-bikes and am wanting to convert my Haro Sonix which I love to ride, however due to health issues I need the ability to be able to either Ghost Pedal or use a throttle to get me home if my illness flares up..

After doing lots of research and reading I have hit a brick wall. The reason is the the Haro has the crank on the rear suspension arm and the connection to the down tube means the the spindle nuts are recessed in to these connectors. The attached photos show it much better than I can explain.

Initially I was looking at a mid mount motor however after seeing how they are mounted I believe that they would not work, I even considered a CYC Gen 4, but again I eliminated it due to the rear arm mounts.

That left me with Hub motors. They would work however then I realised that there was on issue trying to install a pedal sensor. Again the issues was the rear arm mounts.

Any advise on the above would be greatly appreciated.

I think I might have found a solution. I realise that this is a Torque Sensor, I am prefer that, however as I am a newbie I would like input from people that hopefully know allot more than I do.

As I need to climb a hill in order to get back home I am looking at a 48v 750-1000w geared motor. Have looked at 2000-3000 direct drive and they may be an option however I do have to be a little careful as in Aust the max size legal motor 250w. I will be riding it on the street however I live in a small community that police seldom visit.

As I have said any advice would be very much appreciated.

 

[RunForTheHills]

That looks like an Erider torque sensor. They are easier to install because you don't have to drill a hole in the bottom bracket for the wire exit. But that may not work well with your bottom bracket. Grin used to sell a torque sensor from Sempu that might have worked better with your bike, but they had quality control issues with them. You might still be able to get one off of Aliexpress. The Sempu came in different spindle lengths, making it easier to get a good chainline. Grin has one from Fischer on their website, but seems to be only available in a very wide 127mm spindle length.

PAS/Torque Sensors - Control Stuff - Ebike Parts

 

[gromike]

Grin also has a chainring mounted magnet disk for a cadence PAS, so you don't need to mount it on the crank axle.

 

[Firebird]

Grin also has a chainring mounted magnet disk for a cadence PAS, so you don't need to mount it on the crank axle.

Hi, thanks. Will check it out.

 

[Firebird]

That looks like an Erider torque sensor. They are easier to install because you don't have to drill a hole in the bottom bracket for the wire exit. But that may not work well with your bottom bracket. Grin used to sell a torque sensor from Sempu that might have worked better with your bike, but they had quality control issues with them. You might still be able to get one off of Aliexpress. The Sempu came in different spindle lengths, making it easier to get a good chainline. Grin has one from Fischer on their website, but seems to be only available in a very wide 127mm spindle length.

PAS/Torque Sensors - Control Stuff - Ebike Parts

Just checked the part no. and it is Erider. Will take a really close look at the bottom bracket clearance to see how much room there is. Have also looked up the controller and it is Lishui so that is good. It allows you to select voltage and amps when you order Looking at 48v 25amps.

 

[Firebird]

Just took a really close look and it offers T9, T13, T15 and T17.

 

[docw009]

That's a nice bike, but there will be some aesthetic issues mounting a battery in the frame. It will fit on top of the downtube, but be an ugly wart. Good luck avoiding any police attention. Under the frame means you have to wrap it with straps because most cradles aren't strong enough, Inside the frame, most batteries don't fit,

I really like the torque sensor on my mid motor bikes, but not interested in the cost/complexity of putting one on a hub motor. It would cost me maybe $200 for the parts. Instead I can slip pedal assist and use a $12 throttle and feather in power.

If you have the extra budget to spend. I think it's better to start with an old steel bike and geared rear hub motor. After you get some DIY and ebiking under your belt, then look at a motor on the Haro, My first motor kit cost less than what I would have spent on a torque sensor and Cycle Analyst, Still works, and I lucked out on an inexpensive 36V battery that is still serviceable (and didn't explode) 11 years later,

 

[linberl]

Just something to think about: I don't know what your illness is but if it affects your effort, your ability to put muscle into pedaling, you might want to reconsider a torque system. I have a disability which depletes my muscles and needing to pedal a big hill near the end of a ride - when the assist is determined by how much energy I put into pedaling - is a problem. I find a cadence system works much better for me in that regard. My force does not determine the amount of assist as long as I can rotate the crank at all.

 

[Firebird]

Just something to think about: I don't know what your illness is but if it affects your effort, your ability to put muscle into pedaling, you might want to reconsider a torque system. I have a disability which depletes my muscles and needing to pedal a big hill near the end of a ride - when the assist is determined by how much energy I put into pedaling - is a problem. I find a cadence system works much better for me in that regard. My force does not determine the amount of assist as long as I can rotate the crank at all.

I have pinched nerves in my lower back that can shoot pain down both my legs. I am still able to move them so I can ghost pedal so having a throttle when needed would I believe be the best solution. Mind you I am assuming that opening the throttle will provide power to the motor without the need to pedal. Am I correct.

 

[Firebird]

That's a nice bike, but there will be some aesthetic issues mounting a battery in the frame. It will fit on top of the downtube, but be an ugly wart. Good luck avoiding any police attention. Under the frame means you have to wrap it with straps because most cradles aren't strong enough, Inside the frame, most batteries don't fit,

I really like the torque sensor on my mid motor bikes, but not interested in the cost/complexity of putting one on a hub motor. It would cost me maybe $200 for the parts. Instead I can slip pedal assist and use a $12 throttle and feather in power.

If you have the extra budget to spend. I think it's better to start with an old steel bike and geared rear hub motor. After you get some DIY and ebiking under your belt, then look at a motor on the Haro, My first motor kit cost less than what I would have spent on a torque sensor and Cycle Analyst, Still works, and I lucked out on an inexpensive 36V battery that is still serviceable (and didn't explode) 11 years later,

Thanks for your input. Yes it is a nice bike and I understand the limitations of where to place what.I have pinched nerves in my back so I need a full suspension bike as vibration has a tendency to upset them. As far as a battery goes, I don’t expect I will need more than a 7-10.5ah so are looking at the water bottle size as it would be easy to either use the existing mounts or add a additional one.

 

[E-HP]

I am new to e-bikes and am wanting to convert my Haro Sonix which I love to ride, however due to health issues I need the ability to be able to either Ghost Pedal or use a throttle to get me home if my illness flares up..

That left me with Hub motors. They would work however then I realised that there was on issue trying to install a pedal sensor. Again the issues was the rear arm mounts.

I think I might have found a solution. I realise that this is a Torque Sensor, I am prefer that.

As I need to climb a hill in order to get back home I am looking at a 48v 750-1000w geared motor. Have looked at 2000-3000 direct drive and they may be an option however I do have to be a little careful as in Aust the max size legal motor 250w. I will be riding it on the street however I live in a small community that police seldom visit.

A few questions.
How will you normally be riding the bike, when your illness isn't flaring up? Unassisted?
How steep is this hill, what is the grade, and how long? If you have google coordinates, that would help.

If when you have a flare up, and you need to throttle or ghost pedal, a torque sensor won't help, since that requires pedal effort (which is then multiplied). A cadence sensing PAS is what you would want in order to ghost pedal. However, if you had a throttle, would you really need a pedal assist sensor at all?

If it were me, I would get a geared hub as big as you feel wouldn't attract the police. Maybe even paint it to match the color of the bike to be extra stealthy. I wouldn't bother with PAS or even a throttle. I'd just make a little resistor circuit and a couple of push buttons for low and high speed/power, and combine that with a controller that supports a 3 position/speed switch. So, all together you have 6 speeds.
You could use a set of switches like this for the high/low pushbuttons (the left or right momentary turn signal switches). The headlight button could be used for controller on/off. The cops won't know what to make of it.

And the three speed switch on other other side.

For that style bike, I'd put both the battery and controller in an under top tube bag. Very little to indicate that you're riding an ebike, and no throttle they could point to either. Generally I wouldn't recommend the controller go in the bag, but you're not running a lot of power most of the time, especially with the tiny battery. If you stick with the small battery, then cell selection will be important, so it can provide the current needed for the hill.

example:


Knowing how steep and long your hill climb is, and your weight, will make it easy to model in the Grin Simulator in order to determine just how much power you need to climb the hill without pedaling effort. After that, it's easy to select components that will meet your requirements.

Motor Simulator - Web Tools - Resources

Our ebike motor simulator allows you to easily simulate the different performance characteristics of different ebike setups - with a wide selection of hub motors modeled, and the ability to add custom batteries and controllers and set a wide variety of vehicle parameters you'll be able to see...

ebikes.ca

 

[Firebird]

A few questions.
How will you normally be riding the bike, when your illness isn't flaring up? Unassisted?
How steep is this hill, what is the grade, and how long? If you have google coordinates, that would help.

If when you have a flare up, and you need to throttle or ghost pedal, a torque sensor won't help, since that requires pedal effort (which is then multiplied). A cadence sensing PAS is what you would want in order to ghost pedal. However, if you had a throttle, would you really need a pedal assist sensor at all?

If it were me, I would get a geared hub as big as you feel wouldn't attract the police. Maybe even paint it to match the color of the bike to be extra stealthy. I wouldn't bother with PAS or even a throttle. I'd just make a little resistor circuit and a couple of push buttons for low and high speed/power, and combine that with a controller that supports a 3 position/speed switch. So, all together you have 6 speeds.
You could use a set of switches like this for the high/low pushbuttons (the left or right momentary turn signal switches). The headlight button could be used for controller on/off. The cops won't know what to make of it.
View attachment 384156
And the three speed switch on other other side.
View attachment 384157
For that style bike, I'd put both the battery and controller in an under top tube bag. Very little to indicate that you're riding an ebike, and no throttle they could point to either. Generally I wouldn't recommend the controller go in the bag, but you're not running a lot of power most of the time, especially with the tiny battery. If you stick with the small battery, then cell selection will be important, so it can provide the current needed for the hill.

example:
View attachment 384155

Knowing how steep and long your hill climb is, and your weight, will make it easy to model in the Grin Simulator in order to determine just how much power you need to climb the hill without pedaling effort. After that, it's easy to select components that will meet your requirements.

Motor Simulator - Web Tools - Resources

Our ebike motor simulator allows you to easily simulate the different performance characteristics of different ebike setups - with a wide selection of hub motors modeled, and the ability to add custom batteries and controllers and set a wide variety of vehicle parameters you'll be able to see...

ebikes.ca

Thanks for the advice. I do want to be able to ride the bike with some assistance where needed. The hill is only a few hundred yards but is reasonably steep. I am 6ft tall and weigh 220-225lbs. Right now I would say I am not in great shape however I am usually in reasonable condition. I usually play golf twice a week walking and sea kayak on a regular basis.

 

[E-HP]

Thanks for the advice. I do want to be able to ride the bike with some assistance where needed. The hill is only a few hundred yards but is reasonably steep. I am 6ft tall and weigh 220-225lbs. Right now I would say I am not in great shape however I am usually in reasonable condition. I usually play golf twice a week walking and sea kayak on a regular basis.

I’d choose a different donor bike and use a tsdz2b mid drive.

 

[Firebird]

I’d choose a different donor bike and use a tsdz2b mid drive.

Thanks, I had a look for a donor bike however there were very few full suspension bike’s available and they were all north of $1000.

My issue is that I have pinched nerves in my neck and also my lower back. When the ones in my lower back flare up they send shooting pain down my legs which make it hard and painful to pedal. The same applies to walking. I used to love riding my Haro however after several times when I have had to ring my wife to come pick me up I stopped riding.

I have read that some controllers allow you to have different profiles I.e. Torque Sensor and Cadence and that you can switch between them. Is there one that will provide Torque Sensing and Throttle options.

I have been looking at all my options again. A mate is an Aircraft engineer and when we looked at the rear suspension pivot assembly he realised that we could make me a new one for the left that would eliminate the the recess which would potentially allow the installation of a mid drive however we then found that the gearbox would hit the rear suspension arm. I had also found these and based on the information they have provided, it should fit but not sure I want to go that far. Looks like a beast of a set up.

So, I will probably go for a Bafang 750W. I could only find 1000W for fat bikes. Will talk to another mate who is a computer engineer about the circuit you described and will also use the Tool to work out the battery output required.

BTW, I played golf with local Police Sergeant on Saturday and talked about E-Bikes. He said that as long as people ride sensibly and do not give them a reason to stop you, he does not care what power your E-Bike has.

 

[E-HP]

Thanks for your input. Yes it is a nice bike and I understand the limitations of where to place what.I have pinched nerves in my back so I need a full suspension bike as vibration has a tendency to upset them. As far as a battery goes, I don’t expect I will need more than a 7-10.5ah so are looking at the water bottle size as it would be easy to either use the existing mounts or add a additional one.

I’ve been riding my full suspension mid drive for the last several months. I'm using a moderately cushioned mtb saddle. It’s nice for drop offs or riding off a curb, on the bike, but not as good on the body when staying in the saddle. It’s definitely not as plush in the saddle as my hard tail with a long travel thudbuster suspension seatpost and cloud 9 saddle. I can only ride 20 miles or so on the full suspension before it gets uncomfortable, while regularly riding 30 miles on the hard tail setup is no problem. I had high hopes moving to the full suspension, but they didn't pan out for my riding.

 

[yooper2001]

I hear ya....I'm dealing with a degenerating disk... every crack in the road after 10 miles start the pain....I just did what I said I'd never do....I bought a moped style full suspension on clearance ( That made the wife happy) for those bad back days to get out.

 

[Firebird]

Hi guys,

So after much discussion manly with Grin I have decided what I am going to do. However before I do that I thought I would supply all the information I have found so that it may help someone else looking to do the same.

So what I had originally looked at doing was to install a Bafang 750W Rear Hub Motor with a Erider T17 Torque Sensor. This would require a new rear 36 Rim hole and lacing. The problems were how to add a thumb throttle and as suggested a Cadence Sensor as this may be better solution.

The Answer - Cyclist Analyst. It can covert the T17 in to a Cadence Sensor. I also can have a thumb throttle and you can quickly switch between them. Yes, it is not cheap however it did provide a solution to my problem.

Whilst browsing AliExpress I found MTB frames that would be more cost effective than buying a donar bike. So I started pricing up that option which would allow the installation of a Mid Drive. So now I had two solutions however that would mean that the Haro would be set aside and not used.

In the end Option 1 came in at approximately $1300. Option 2 came in just under $1850.

So which one am I going for, Option 3.

In researching MTB frames I also found E-Bike Full Suspension MTB frames and so I priced out this option. Looked at two motors, the Bafang M410 and the M510. The first was $2200, the second was $2350.

I also buy from Alibaba.com and I received an email promotion from the company I had enquired about for the frame and the M510 kit. They have a complete bike with M510 for $2387.19 including shipping. Naturally I then checked this company out and they are legit. The benefit of spending lots of time in China for work is that I have contacts there that are able to validate a company.

So here is what I plan to buy. Will provide photos etc when it arrives.

One last thing, my wife bike is not great so I plan to give her the Haro.

Thanks for all your advice.

 

[linberl]

I have pinched nerves in my lower back that can shoot pain down both my legs. I am still able to move them so I can ghost pedal so having a throttle when needed would I believe be the best solution. Mind you I am assuming that opening the throttle will provide power to the motor without the need to pedal. Am I correct.

Just saw this. Yes, a throttle means no pedaling. You might want to make sure you get a system that has cruise control - holding the throttle for more than a minute or two is a pita. And I'm assuming Australia doesn't have laws restricting throttles on e-bikes like some US states do.

 

[Firebird]

Just saw this. Yes, a throttle means no pedaling. You might want to make sure you get a system that has cruise control - holding the throttle for more than a minute or two is a pita. And I'm assuming Australia doesn't have laws restricting throttles on e-bikes like some US states do.

They do, you need to ghost pedal. And yes the system I am looking at has cruise control.