Tonaro power problem

[alban]

Just got an ex-demo Tonaro-type bike - not from Powerpedals so no support! Attracted by the presumed crank drive hillclimbing advantage. Added, with some difficulty, a 36V Hall throttle via spare 3-pin JLT connector - works.
Problem is, in the lowest gears, when I apply throttle it's as if the power tails off and there is no graduated increase in power with turning the throttle - it seems weak, as if the motor is becoming 'disengaged'. In fact it goes better up a gentle incline in 4th gear (of 8) but I know I'll need full power in these lowest gears! it's not the speed limiter as I'm nowhere near 22kph. It has a pedelec function too which seems to give a bit more power in those lowest gears but again tails off.
Is there some kind of limitation based on crank rotation speed via the pedelec wheel or summat? I suspect the battery isn't the best either but as I've said there is more power present in 4th and less 'torque' in the 3 lowest gears which is odd.
Any ideas?

 

[mike killay]

Exactly what bike is this?
Only this years Tonaros (Late summer onwards) are available without throttles in the UK.
When you say you do not have any power in low gear, are you on a hill?
In bottom, the bike will only do about 4 mph anyway.
If, as you say, the power tails off, do you mean the bike slows down or is it that it just stops accelerating?
This throttle that you added might not be very sensitive and just be all or nothing.

 

[alban]

It's not badged Tonaro but is exactly like a Bighit 4. 200W CATIC motor.

You say it only goes 4mph in lowest gear? That surprises me. Yes it stops accelerating after hitting prob about 4mph on a gentle incline rather than slowing. Is it limited electronically then?
Throttle has some definite graduation in it but it's a basic scooter/ebike Hall model.

 

[Blew it]

Well, I'm not too good with electronics, but is it possible the throttle you are using is 10k ohm instead of the more usual 5k ohm found on E-bikes.

 

[mike killay]

The bottom gear on a Bighit is only 34 inches. get the bike on the flat and in top gear. It should easily go up to 15mph, maybe a little more. As you come down the gears, maximum speed will naturally decrease. If it is running out of steam, then as you say, the battery maybe suspect.

 

[alban]

Yeah it was more the pulling power up hills that I was looking for rather than speed. I was expecting it to have more torque in the lower gears but it felt like it hit a brick wall in bottom, up what was a very gentle incline.

 

[Blew it]

Alban,

At the moment I'm not really sure what the problem is, but I'm sure it can be fixed. If needs be, I will post a pic of the controller and connections on my BigHit to see if we can resolve this issue.

A few possibilities.

At the risk of teaching my granny how to suck eggs, did you establish the JST-SM3 2.5 you connected your throttle too is in fact a throttle input? With the machine switched on, one pin will show +5v, one will show -0v and the third pin will be the signal return path. Sometimes the colour coding of the wires do not follow any conventions, some are conventional, red, black and another colour for signal return.

The throttle you are connecting. Was it supplied with a pin-out diagram or description? If not, the pin-outs can be established with a multimeter and a PP3 battery. Connect the PP3 + to the suspected +5v input on the throttle, connect the PP3 -0v to the suspected -0v input on the throttle. Place one multimeter probe on the -0v connection and the other probe on the suspected signal return. Operating the throttle should show an ascending voltage, starting at around .75v up to the voltage of the PP3.

"....it felt like it hit a brick wall in bottom....."

Unrestricted, the Tonaro machines will assist to around 18 mph on a fully charged battery. In order to comply with EU and British regulations, the machines are fitted with restrictors. A magnetic sensor is fitted to the chainstay, the magnet that operates the switch is fitted to one of the rear wheel spokes. The controller measures the time lapsed between each pass of the magnet over the sensor. When this time lapse equals 15 mph, the inhibitor circuit ( also used by the brake switches ) is activated and the electrical assistance cuts out, abruptly!

Try this.

Locate the magnet on one of the rear wheel spokes and remove it. This will disable the speed restrictor.

Some more info would be useful. Your machine was supplied as pedelec only, does it have switched brake levers? Does your machine have a three position mode switch on the handlebars?

This is just a start, but I think you have enough to keep you busy for the time being

Regards
Bob

 

[Blew it]

An interesting thread on Endless-sphere for Tonaro enthusiasts

CLICK

 

[alban]

Bob thanks for your time and trouble! I'm encouraged.
In reply:
The throttle connector seems to work with the throttle giving a nicely graduated response when not moving (wheel lifted off ground) or when moving in a higher gear.
I checked the connector side for 5V supply and signal. Also checked the 4 lead throttle using a battery holder power source and discovered the variable signal and display leads. I insulated the display lead and plugged in red to the 5v (purple) lead and black to the black earth lead. Seemed to work! It was advertised as a scooter throttle but I'd seen a few described as interchangeable.....
I spotted the magnet and have now slid it down towards the hub out of the way. I'll check any difference on the morrow. However it wasn't that it was cutting out due to speed/wheel rotation. In first it just accelerated to about 4mph and then seemed to stick at that pace - full throttle seemed to cause no subsequent increase in speed but does when in a higher gear. I was expecting greater torque and the ability to accelerate up such a gentle slope in low gear!
It does have brake switches that cut the motor and it does have a batt/on or off/3 power mode display. I have always selected max. The battery seemed to run down quickly but I was doing a lot of starts up a 3-4% gradient. The funny thing is that it seems to climb this slope better in 4th which seems paradoxical to me!
Yes I read all around about this bike and was impressed with reports of its climbing ability. That's why I'm a bit taken aback.

 

[Deleted member 4366]

It's probable that the crank is speed-limited, or the motor is reaching its max rpm, so you have to keep changing up before it reaches its speed limit. Does the crank actually turn faster in 4th gear compared with first?

 

[Blew it]

In first it just accelerated to about 4mph and then seemed to stick at that pace .

Ah! That's interesting. Seems to suggest the controller firmware is programmed for EU use. European regulations do permit the use of an independant throttle, but only to a maximum 6kph ( around 4mph ) covered by 'pedestrian controlled vehicle' regs, otherwise known as a walk-alongside-throttle.

For the time being, forget about the throttle and see how the machine performs in pedelec mode with the wheel magnet out of position. With this done the machine should perform in the way the designers intended, this is what you should expect:

Position 1 on the mode console, assistance to around 13mph.
Position 2, assistance to around 16mph
Position 3, assistance to around 18mph on a freshly charged battery.

In all instances, the assistance will die away gradually according to which level is selected on the console. In other words, the assistance will taper off gently as voltage maximum is reached rather than suddenly stopping as if "hitting a brick wall".

If the outcome of your test ride with the wheel magnet removed is satisfactory, then it may be that the controller will have to changed to allow the full use of an independant throttle. Phil at PowerPedals can supply a replacement controller for around £50

36 volt controller.

All else being well, and providing you could overcome any difference in the connectors, this would convert your machine to the same specification as my own Tonaro BigHit.

Have fun

Bob

 

[Deleted member 4366]

Blew it: How fast does your Bighit go in first gear?

 

[Blew it]

I haven't a clue, but after re-reading the first posting I understand your line of thought.

The voltage maximum speeds for each mode I quoted are for top gear. Thinking about this, yes of course it would be very much lower in first gear, but I still don't understand the "hitting a brick wall" bit. Thinking these problems through certainly exercises the grey matter.

I never ride on throttle only, but for the benefit of those who do, I carried out some throttle only hill-climbing at the end of the "Cricklade Country Way" thread. In third gear, the machine slowed to 4.8 mph at the steepest point of 11.8%, accelerating to 9 mph in third gear on the less steep parts.

Anyway, let's see how Alban gets on with the wheel magnet removed, I'm sure a combined effort will sort this out.

 

[mike killay]

One of the problems is that we are not too sure what this bike is. I know that the Tonaro is re-badged as Martin, Gette etc. in other countries and as far as I am aware it was only the latest batch to arrive in the UK that did not have a throttle.
The age of the battery is crucial, if the bike is some older import, it may well be that the battery is on its last legs.
Also, I am not sure what the OP is expecting when accelerating in lowest gear. Until he can ride up some hills and replicate Blew It's figures, we don't know if the bike is performing normally or not. The silence of the motor can deceive and you will not realise that it is running flat out.
I live at the top of a hill, part of it is about 1 in 8. I ride up this in second gear with light pedalling at 6.5mph

 

[Blew it]

Agreed Mike, I should also add, I weigh 72 kgs, or 11st 5 lbs.

 

[mike killay]

I weigh over 100 kilos!!!!
Seriously though, if you are used to petrol engines the characteristics of an electric motor are strange in that torque increases as the motor slows. On a few occaisions I have been pedalling up a hill and been confronted by an extra steep bit such as where a driveway crosses the path. I expect the engine to stall, but as it slows you feel the extra shove. Bear in mind that 200 watts is just over quarter of a horsepower and it may be that the OP is expecting too much.
My old cyclemaster from the 1950's was about 0.8hp and in reality did not seem all that much more powerful.
There is a local hill which the cyclemaster would just about get up unaided, probably about 12-14 mph. Of course it did not have any gears, but my Tonaro will go upthis unaided in 4th at about 9mph.
I am quite tempted to get hold of an old cyclemaster for comparisons sake!

 

[flecc]

I am quite tempted to get hold of an old cyclemaster for comparisons sake!

I think you'd be surprised at how poor it really was in comparison with our e-bikes. The characteristics of very small petrol engines didn't really fit the need, and the Cyclemasters were the weakest of all those we used to fit and service. That applies to both versions, black 25 cc and grey 32 cc.

 

[mike killay]

I think you'd be surprised at how poor it really was in comparison with our e-bikes. The characteristics of very small petrol engines didn't really fit the need, and the Cyclemasters were the weakest of all those we used to fit and service. That applies to both versions, black 25 cc and grey 32 cc.

The noise and vibration were the main drawbacks. But three of us did something like a 300 mile trip because we were able to carry spare petrol which was about its only advantage. Of course we treated them as motorbikes and only pedalled when going up hills.

 

[flecc]

Of course we treated them as motorbikes and only pedalled when going up hills.

Like almost everyone in those days, the concept of pedal assist seemed mostly absent back then.

 

[Deleted member 4366]

My thought is that if the motor is wound for just over 15mph with a 11/34 cassette, then the maximum speed in first gear will be about 5mph. Even if it could do 18mph in top, that would still be less than 6mph in first. The whole idea of a crank drive is that you can gear down for more torque to climb hills, but you have less speed. You can't have both! The same as pedalling: How fast can anyone pedal in first gear? To me it seems that OP's bike may be working as it should.