This section covers information that might be of use to potential buyers and existing owners and includes technical information and possible customising modifications.
Sprockets and gears
The chainwheel is 41 tooth, the Nexus hub sprocket 22 tooth, chain and sprockets 1/8". With a gear range of 244% the gear inches are: 33", 37", 44", 51", 59", 69", 80".
Cadence in top gear at 15.5 mph is 65. I managed a short period of pedalling at 27 mph on a gentle 6% downhill with a 113 cadence, but at the optimum cadence of 90, the road speed is 21.4 mph. A typical e-bike riders top cadence of 70 produces 16.7 mph.
Anyone finding the top gear too low can simply change the rear hub sprocket. These are available from your local cycle dealer or SJS in 16 to 24 tooth 1/8" sizes. A 16 tooth would theoretically give a maximum but illegal assisted speed of over 21 mph, though the power phase down commencement now around 16.5 mph would probably mean a maximum of 19 mph by using high power mode. Of course the steepest hill that could be climbed would correspondingly suffer, but for anyone who doesn't have hills over 10%, it could be practical, and the cadence at 15.5 mph would be reduced to 47. Probably a more universally practical choice would be a 19 tooth rear sprocket giving a maximum assist speed of 18 mph / 29 kph and a cadence at 15.5 mph of 56. Warning: On bikes using the Panasonic systems, altering the gearing up or down from the designed optimum often reduces the range, the greater the change, the greater the loss.
The motor drive sprocket is a 9 tooth fitted onto a tapered splined shaft with a securing circlip, and these are also manufactured in 8 and 11 tooth sizes. Changing that would alter the relationship of the motor drive to gear hub without affecting the ratio of the chainwheel to gear hub drive, but would be unlikely to give any advantage in normal circumstances. The different sizes are for other purposes, 8 tooth for the low power only motor or for extra hill climb ability, and 11 tooth to raise the chain speed for some other applications like small wheel bikes. See the Repairs section below for changing this.
Seat post. For the cyclist who prefers a rigid one, the correct size to buy is 27.2 mm.
Sprockets and gears
The chainwheel is 41 tooth, the Nexus hub sprocket 22 tooth, chain and sprockets 1/8". With a gear range of 244% the gear inches are: 33", 37", 44", 51", 59", 69", 80".
Cadence in top gear at 15.5 mph is 65. I managed a short period of pedalling at 27 mph on a gentle 6% downhill with a 113 cadence, but at the optimum cadence of 90, the road speed is 21.4 mph. A typical e-bike riders top cadence of 70 produces 16.7 mph.
Anyone finding the top gear too low can simply change the rear hub sprocket. These are available from your local cycle dealer or SJS in 16 to 24 tooth 1/8" sizes. A 16 tooth would theoretically give a maximum but illegal assisted speed of over 21 mph, though the power phase down commencement now around 16.5 mph would probably mean a maximum of 19 mph by using high power mode. Of course the steepest hill that could be climbed would correspondingly suffer, but for anyone who doesn't have hills over 10%, it could be practical, and the cadence at 15.5 mph would be reduced to 47. Probably a more universally practical choice would be a 19 tooth rear sprocket giving a maximum assist speed of 18 mph / 29 kph and a cadence at 15.5 mph of 56. Warning: On bikes using the Panasonic systems, altering the gearing up or down from the designed optimum often reduces the range, the greater the change, the greater the loss.
The motor drive sprocket is a 9 tooth fitted onto a tapered splined shaft with a securing circlip, and these are also manufactured in 8 and 11 tooth sizes. Changing that would alter the relationship of the motor drive to gear hub without affecting the ratio of the chainwheel to gear hub drive, but would be unlikely to give any advantage in normal circumstances. The different sizes are for other purposes, 8 tooth for the low power only motor or for extra hill climb ability, and 11 tooth to raise the chain speed for some other applications like small wheel bikes. See the Repairs section below for changing this.
Seat post. For the cyclist who prefers a rigid one, the correct size to buy is 27.2 mm.
Kalkhoff Agattu Pedelec - Extra
A tiny bell, seen here, is neatly and cleverly integrated into the rear brake lever. Although surprisingly effective for it's size, some riders like to fit something rather noisier.
Since putting one next to the handgrip would inconveniently move the Power & Mode control away, a right hand auxilliary bell or horn would probably be operationally preferable.
Since putting one next to the handgrip would inconveniently move the Power & Mode control away, a right hand auxilliary bell or horn would probably be operationally preferable.
The charger instructions in the manual warn that the battery should not be left on the charger for more than 48 hours after charging. I've no idea why this unusual instruction is there, but as the battery has three active connections with the charger, unusual with a Li-ion, that may be an issue. It seems likely that the charger and battery share in the monitoring of the charge process via the additional connection, so a long term connection to the monitoring circuit could have a consequence.
The Nexus 7 gear hub normally needs no slowing of pedalling to change up, and barely any to change down. However, as the drive pressures of both rider and motor are on the gears, an easing of pedal pressure when changing up and a momentary pause when changing down are desirable in the interests of a long troublefree life from the hub.
Maintenance. The Panasonic motor unit needs no routine maintenance, being a sealed unit pre-lubricated in manufacture. The remainder of the bike just needs a normal level of cycle attention from time to time, but with one exception. The motor, as well as the rider, driving through the chain and sprockets places higher loadings than normal on those, so regular lubrication is important to keep wear low. Either use dedicated good quality cycle grease or oil according to preference, and in the case of oil I'd suggest an every day user should aim to lubricate the chain every week to achieve the best life for the chain and both the motor and bike sprockets. For the technical, after taking into account the difference in all three sprocket sizes and the difference in wheel size, the tooth pass rate on this latest Panasonic motor's drive sprocket is 40.7% higher. Hence the emphasis on good and regular chain lubrication.
Repairs. The build quality and components should ensure a long and troublefree life, and any replacements and repairs on the cycle side are easily carried out by a knowledgeable owner or cycle shop with no more difficulty than on an ordinary bike. The only normally wearing replaceable item on the motor unit is the motor's chain drive sprocket, the symptom of it being worn being the drive suddenly snatching and jerking as the sprocket teeth jump chain links. The sprocket can easily be changed by an owner used to doing their own cycle repairs or a cycle shop following these instructions if necessary, with the replacement sprockets available from the bike supplier. There's also a "quick fix" to keep going without a replacement sprocket in those instructions.
Rider Power Contribution
Panasonic refer to the power applied by the motor as 0.5 times the rider's input in Eco mode, which I shall ignore, 1 times the rider input in Standard mode, and 1.3 times rider input in High Power mode. So what are these in practice? I've done some test climbs with moderate effort on both a 14% (1 in 7) hill and a 20% (1 in 5) hill, and calculated the total power required, together with the human and motor proportions in both High Power and Standard mode. These are based on my 70 kilos weight, plus 2 kilos for additional clothing, the bikes weight, and between 15 and 30 watts added according to speed for roll resistance, frictions, lubricant drag and wind resistance at these low speeds:
Gradient Climb Speed Total Power Needed Power Mode Contribution in Watts
Human Motor
14% 7.5 mph 490 watts High 213 277
14% 7.5 mph 490 watts Standard 245 245
14% 6 mph 386 watts High 168 219
14 % 6 mph 386 watts Standard 193 193
20% 5.5 mph 492 watts High 214 278
20% 5.5 mph 492 watts Standard 246 246
20% 4.5 mph 400 watts High 174 227
20% 4.5 mph 400 watts Standard 200 200
From these figures you can see how speed and steepness affect the required power, and how the differences between High and Standard power modes are numerically very small. Reducing speed has a far greater effect than changing power modes. For example, at 7.5 mph on a 14% hill in Standard mode, changing to High Power saved me 32 watts of effort, but cost the motor and battery the same 32 watts extra. Alternatively, slowing very slightly to 6 mph and leaving it in Standard mode saved me 52 watts of effort, saved the motor 52 watts of effort as well and reduced the load on the battery.
You might wonder how the small differences between High and Standard mode numbers can make much of a difference in practice, but in fact very small changes in power can have a remarkable effect. On one e-bike with 576 watts of gross power I owned, the very high motor gearing made it a poor hill climber, only just managing 6% slopes on power only. After a conversion which increased it's power by just 50 watts, it was able to climb 10% hills faster than it used to reluctantly climb 6% hills and be like any e-bike with normal motor gearing. That's all it needs to make a big difference, a very small increase.
The earlier Panasonic motor unit had peak power of 390 watts, and this motor appears to be the same one, though supplied with a higher voltage which equates to 436 watts now, this depending on the controlling circuit though. But you can see that the motor power outputs I've shown above are nowhere near either figure.
The answer lies in the ratio of rider to motor power, for I'd have to exert 315 watts of power for the 1.3 times support from the motor to be over 400 watts at 417 watts, the 732 watts of total power then able to carry me up a 20% hill at 8 mph, or up a 14% hill at 12 mph. But I've got to be that strong first!
So how strong is that, and what do these watts mean? As part of their efforts at lobbing people into space in the 1960s, NASA researched human performance and came up with a variety of useful numbers on many activities, including for cycling. Their wattage output figures for "healthy men", presumably meaning fit males from about 25 to 45 years old given their astronaut profiles at the time, showed the following outputs:
300 watts for about 10 minutes continuous.
200 watts for about 1 hour continuous.
100 watts for about 5 hours continuous.
Above those, an example from the world of top cycling is that of the legendary Miguel Indurain on a climb of La Plaque during the 1995 Tour de France, who expended a calculated continuous 450 watts for exactly 1 hour, putting we mere mortals firmly in our places. He hasn't done anything on my nearest hill yet though, so the record for that was still open for me to set. So after those steady 14% (1 in 7) tests above, I did a sprint up the hill in 6th gear High Power mode, standing on the pedals and giving it my maximum. It's only short, taking about 20 seconds, but the maintained speed was 13 mph (20.8 kph). On this bike with my weight and the other factors allowed for, that needed 798 watts, and at the 1.3 assist ratio if the motor was topping out at it's assumed 436 watts peak output, I was left with the remainder of at least 362 watts over those few seconds.
From all this information, you could roughly adjust for your age and relative fitness and get a reasonable assessment of what you might be capable of outputting in watts.
If as a result you're worried that you might not be strong enough to ride this bike, note that my examples at the start of this section were of two of the steepest hills, and most don't have those in their areas. On the more typical steep hill that most people encounter in their area, one of 10% (1 in 10), if ridden by me in High Power mode at 5 mph would require just 230 watts with only 99 of those watts coming from me, and at the slowest cycling speed of 4 mph, I'd only need to put in 78 watts, little more than the 50 watts that is required during sitting down.
The Nexus 7 gear hub normally needs no slowing of pedalling to change up, and barely any to change down. However, as the drive pressures of both rider and motor are on the gears, an easing of pedal pressure when changing up and a momentary pause when changing down are desirable in the interests of a long troublefree life from the hub.
Maintenance. The Panasonic motor unit needs no routine maintenance, being a sealed unit pre-lubricated in manufacture. The remainder of the bike just needs a normal level of cycle attention from time to time, but with one exception. The motor, as well as the rider, driving through the chain and sprockets places higher loadings than normal on those, so regular lubrication is important to keep wear low. Either use dedicated good quality cycle grease or oil according to preference, and in the case of oil I'd suggest an every day user should aim to lubricate the chain every week to achieve the best life for the chain and both the motor and bike sprockets. For the technical, after taking into account the difference in all three sprocket sizes and the difference in wheel size, the tooth pass rate on this latest Panasonic motor's drive sprocket is 40.7% higher. Hence the emphasis on good and regular chain lubrication.
Repairs. The build quality and components should ensure a long and troublefree life, and any replacements and repairs on the cycle side are easily carried out by a knowledgeable owner or cycle shop with no more difficulty than on an ordinary bike. The only normally wearing replaceable item on the motor unit is the motor's chain drive sprocket, the symptom of it being worn being the drive suddenly snatching and jerking as the sprocket teeth jump chain links. The sprocket can easily be changed by an owner used to doing their own cycle repairs or a cycle shop following these instructions if necessary, with the replacement sprockets available from the bike supplier. There's also a "quick fix" to keep going without a replacement sprocket in those instructions.
Rider Power Contribution
Panasonic refer to the power applied by the motor as 0.5 times the rider's input in Eco mode, which I shall ignore, 1 times the rider input in Standard mode, and 1.3 times rider input in High Power mode. So what are these in practice? I've done some test climbs with moderate effort on both a 14% (1 in 7) hill and a 20% (1 in 5) hill, and calculated the total power required, together with the human and motor proportions in both High Power and Standard mode. These are based on my 70 kilos weight, plus 2 kilos for additional clothing, the bikes weight, and between 15 and 30 watts added according to speed for roll resistance, frictions, lubricant drag and wind resistance at these low speeds:
Gradient Climb Speed Total Power Needed Power Mode Contribution in Watts
Human Motor
14% 7.5 mph 490 watts High 213 277
14% 7.5 mph 490 watts Standard 245 245
14% 6 mph 386 watts High 168 219
14 % 6 mph 386 watts Standard 193 193
20% 5.5 mph 492 watts High 214 278
20% 5.5 mph 492 watts Standard 246 246
20% 4.5 mph 400 watts High 174 227
20% 4.5 mph 400 watts Standard 200 200
From these figures you can see how speed and steepness affect the required power, and how the differences between High and Standard power modes are numerically very small. Reducing speed has a far greater effect than changing power modes. For example, at 7.5 mph on a 14% hill in Standard mode, changing to High Power saved me 32 watts of effort, but cost the motor and battery the same 32 watts extra. Alternatively, slowing very slightly to 6 mph and leaving it in Standard mode saved me 52 watts of effort, saved the motor 52 watts of effort as well and reduced the load on the battery.
You might wonder how the small differences between High and Standard mode numbers can make much of a difference in practice, but in fact very small changes in power can have a remarkable effect. On one e-bike with 576 watts of gross power I owned, the very high motor gearing made it a poor hill climber, only just managing 6% slopes on power only. After a conversion which increased it's power by just 50 watts, it was able to climb 10% hills faster than it used to reluctantly climb 6% hills and be like any e-bike with normal motor gearing. That's all it needs to make a big difference, a very small increase.
The earlier Panasonic motor unit had peak power of 390 watts, and this motor appears to be the same one, though supplied with a higher voltage which equates to 436 watts now, this depending on the controlling circuit though. But you can see that the motor power outputs I've shown above are nowhere near either figure.
The answer lies in the ratio of rider to motor power, for I'd have to exert 315 watts of power for the 1.3 times support from the motor to be over 400 watts at 417 watts, the 732 watts of total power then able to carry me up a 20% hill at 8 mph, or up a 14% hill at 12 mph. But I've got to be that strong first!
So how strong is that, and what do these watts mean? As part of their efforts at lobbing people into space in the 1960s, NASA researched human performance and came up with a variety of useful numbers on many activities, including for cycling. Their wattage output figures for "healthy men", presumably meaning fit males from about 25 to 45 years old given their astronaut profiles at the time, showed the following outputs:
300 watts for about 10 minutes continuous.
200 watts for about 1 hour continuous.
100 watts for about 5 hours continuous.
Above those, an example from the world of top cycling is that of the legendary Miguel Indurain on a climb of La Plaque during the 1995 Tour de France, who expended a calculated continuous 450 watts for exactly 1 hour, putting we mere mortals firmly in our places. He hasn't done anything on my nearest hill yet though, so the record for that was still open for me to set. So after those steady 14% (1 in 7) tests above, I did a sprint up the hill in 6th gear High Power mode, standing on the pedals and giving it my maximum. It's only short, taking about 20 seconds, but the maintained speed was 13 mph (20.8 kph). On this bike with my weight and the other factors allowed for, that needed 798 watts, and at the 1.3 assist ratio if the motor was topping out at it's assumed 436 watts peak output, I was left with the remainder of at least 362 watts over those few seconds.
From all this information, you could roughly adjust for your age and relative fitness and get a reasonable assessment of what you might be capable of outputting in watts.
If as a result you're worried that you might not be strong enough to ride this bike, note that my examples at the start of this section were of two of the steepest hills, and most don't have those in their areas. On the more typical steep hill that most people encounter in their area, one of 10% (1 in 10), if ridden by me in High Power mode at 5 mph would require just 230 watts with only 99 of those watts coming from me, and at the slowest cycling speed of 4 mph, I'd only need to put in 78 watts, little more than the 50 watts that is required during sitting down.
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3.12.2007
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The Continental CityRide tyre fitted is a key part in the free rolling performance of the Kalkhoff Agattu, and strong though my allegiance to Schwalbe's Marathon Plus tyres is, I would not change to them on this bike. The puncture resistance built in to these is unlikely to be quite as good as the Schwalbe, but with no hub motor, a very rare puncture is easily dealt with.
active and part charged when received. Although then usable, they still need to be fully charged, and these batteries tend to achieve the highest capacity when they are initially fully charged and then completely discharged on the bike two or three times until the low battery LED indication flashes. In typically Japanese fashion, Panasonic are usually very careful to make no mistakes, so it was amusing to spot the spelling of "remaining" on the battery's level gauge, seen here.
The battery has two states from which the first charge is done. The bike's manual refers to it being received in "sleep mode", from which no current can be drawn until it's fully charged before first attempting to ride. It's likely that state occurs when the battery has been stored before delivery, since those from the first production have been already