Cutting off my nose...

[flecc]

Its dfficult for me to say how fast your whisks will be blending as the top gear (at least) was not working. I found my legs spinning rapidly for not much speed. The second bike I rode (modded) felt more like the torq in terms of speed but also had the other benefits I mentioned before

The cadence (pedal rpm) is 65 at the legal maximum of 15.5 mph on the Kalkhoffs, the same for Agattu and Pro-Connect as standard due to the law.
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[HarryB]

The cadence (pedal rpm) is 65 at the legal maximum of 15.5 mph on the Kalkhoffs, the same for Agattu and Pro-Connect as standard due to the law.
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I think I am going to be disappointed after the torq then!

 

[stokepa31]

Thanks Flecc

I prefer more resistance than that so a smaller number of teeth will be in order when I get round to purchasing. I dont know what that means for the motor and whether it assists for longer at higher speed and to be honest I wouldnt care too much. just want that extra reserve of resistance to allow me to add extra speed via muscle power as I do with the torq.

Paul

 

[flecc]

I think I am going to be disappointed after the torq then!

Only until you change the rear sprocket though Hal. The 7 or 8 gears go so low that these bikes easily pull higher speeds while retaining low enough gearing for steep hills. That's especially true now with the high power mode availability.

An 18 tooth sprocket reduces the cadence to 53 at the legal speed, or conversely, at that moderate 65 cadence you'd get 19 mph, probably about ideal for most territories.

Bear in mind that I hit 27 mph on a slight downslope with the standard gearing for a short stretch, though my legs were probably invisible, and at the generally accepted physiological optimum of a 90 cadence, the standard gearing gives 21.4 mph.

Using an 18 tooth sprocket will increase the assist range as well of course, delaying the phase down of power. The latter is the biggest difference that you'll notice, the power assist declining with speed of pedalling.
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[Citrus]

18 tooth rear sprocket on the Agattu

I fitted an 18T rear sprocket to my Agattu wave about 2 weeks after I got it and it improved the gearing for my purposes. I generally cycle in 5th 6th or 7th gear, except for steepish hills where I use 3rd and 4th gear (and very occassionally 2nd gear). I have never needed to use 1st gear - and that is with the bike modded.

On a flat in ideal conditions (i.e no headwind) I can cycle in 7th gear at between 20-22 mph (motor no longer even helping) without feeling my legs are going like a whisk. Battery range drops when changing to an 18T rear sprocket - but I still get 20-25 miles in hilly adverse conditions and 30-40 miles in ideal conditions. Top speed so far has been downhill no wind assist - a respectable 36.8 mph - and the bike still felt pretty stable, just the brakes aren't good enough at that speed.

 

[simonbarnett]

I am sure it will come down to whether you can afford the Kalkhoff in the end.

2 things interest me here:

1. The Kalkhoff at it's introductory price is similar cost to the Wisper SE and the top end Ezees so that may come down to preference, with the cheaper end being hub dominated.

2. I'm surprised the Agattu test bike still has faulty gears- why aren't they repaired by now?

 

[flecc]

2. I'm surprised the Agattu test bike still has faulty gears- why aren't they repaired by now?

I'm a bit surprised, but it could be availablity. These days, hub gear manufacturers don't supply spares usually, just whole new hub gear inserts, and they are sometimes not available for long periods when cycle manufacturing demand for hubs is high, as I know it is at present.

I had the same problem with an SRAM P5 last year, but eventually managed to find a whole hub in stock somewhere from which I could take the insert.
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[simonbarnett]

Well let's hope some spares are coming with the long awaited delivery

 

[flecc]

Well let's hope some spares are coming with the long awaited delivery

These sort of spares are usually via wholesalers rather than bike manufacturers. I just had a very quick Shimano hub gear hunt and found one source with the Nexus 8 and it's fitting kit, no sevens or threes and no inserts for any of them! It wasn't a thorough search, but it indicates the position isn't easy at present.
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[stokepa31]

Flecc

what would happen with the motor if you fit lower teeth on the rear? would it assist still at the higher speed. I'm assuming it would. Wonder what happens if you go even smaller that 18

Paul

 

[Erik]

My local ALDI recently had an offer for pushbikes with SRAM 7-speed gear hub and hub dynamo.

The price? A whopping £210 or probably half the price of the spares bought seperately.

 

[flecc]

Flecc

what would happen with the motor if you fit lower teeth on the rear? would it assist still at the higher speed. I'm assuming it would. Wonder what happens if you go even smaller that 18

Paul

Yes it will assist at higher speeds Paul, but eventually the motor power would be insufficient to cope at all, and the range would drop a lot since the bike would spend much of it's time in the highest power point of the software provision.

I've mentioned in here a few times the Lafree Twist Panasonic bikes that some have added the Xtracycle extension to, a couple with SRAM DualDrives. With that derailleur combination the smallest rear sprocket will be about 11 teeth, and the hub gear part of the DualDrive reduces that when in it's top gear to an effective 8 tooth.

On the new Panasonic units, in theory that would provide power assist at the maximum level up to about 27 mph, with the assist phasing down from there until ending at nearly 43 mph, but of course the power available could not do that on the flat, although one could have some wicked fun down quite gentle slopes and astonish anyone seeing it.

Realistically I think a 16 tooth would be about the limit, and you might find that gearing would leave the bike a bit weak into headwinds and on slight slopes in top gear, necessitating more gear changing than usual. Consumption would rise again too.
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[flecc]

My local ALDI recently had an offer for pushbikes with SRAM 7-speed gear hub and hub dynamo.

The price? A whopping £210 or probably half the price of the spares bought seperately.

Isn't this so often the case Erik. The complete SRAM hub I bought for it's inner was on offer at much less that the normal price for the inner only. It's a mad world, but never boring.
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[HarryB]

Only until you change the rear sprocket though Hal. The 7 or 8 gears go so low that these bikes easily pull higher speeds while retaining low enough gearing for steep hills. That's especially true now with the high power mode availability.

An 18 tooth sprocket reduces the cadence to 53 at the legal speed, or conversely, at that moderate 65 cadence you'd get 19 mph, probably about ideal for most territories.

Bear in mind that I hit 27 mph on a slight downslope with the standard gearing for a short stretch, though my legs were probably invisible, and at the generally accepted physiological optimum of a 90 cadence, the standard gearing gives 21.4 mph.

Using an 18 tooth sprocket will increase the assist range as well of course, delaying the phase down of power. The latter is the biggest difference that you'll notice, the power assist declining with speed of pedalling.
.

I was hoping to get away without the gearing mod but I will just have to see how I get on. Even with the standard gearing I should still be able to go 17mph without legs whisking (as you were able to go 27mph). Having read your review again I think realistically 19/20 teeth will be the best compromise (I do want to do the majority of the work myself).

One question. At the moment I have a charger at work but I plan not to do the same with the agattu. I know that I should charge every time I use it but the charger is expensive and would go some way towards replacing the battery some time after year 2. I will go 20.24 miles a day - does this make economic sense? The arrival of the (cheaper?) portable charger may change this but it would be great not to have to carry the battery into work. It would certainly avoid having to explain what it is every five minutes!

All this talk and I will start getting excited about the delivery!

 

[flecc]

I wouldn't buy a second charger Hal, I'd just ride the 20 plus miles each day. The higher the quality of the battery and the better it's management, the less important the charge frequency becomes, the software protecting the battery well. Even at a high rate of drain on these bikes your journey is less than two thirds range, and on average nearer a half, so no problems with the 20 miles.

If you want to do much of the work yourself you may not need to change the sprocket at all, the bike very free running from 16 mph up, much more so then the Torq, so you'd enjoy the pedalling as much as I did. After a couple of hundred miles they become even more free running with everything bedded in, and that's when it's worth having no-power test rides on Torq and Kalkhoff. The difference from the hub-motor bike will surprise you.
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[stokepa31]

Yes it will assist at higher speeds Paul, but eventually the motor power would be insufficient to cope at all, and the range would drop a lot since the bike would spend much of it's time in the highest power point of the software provision.

I've mentioned in here a few times the Lafree Twist Panasonic bikes that some have added the Xtracycle extension to, a couple with SRAM DualDrives. With that derailleur combination the smallest rear sprocket will be about 11 teeth, and the hub gear part of the DualDrive reduces that when in it's top gear to an effective 8 tooth.

On the new Panasonic units, in theory that would provide power assist at the maximum level up to about 27 mph, with the assist phasing down from there until ending at nearly 43 mph, but of course the power available could not do that on the flat, although one could have some wicked fun down quite gentle slopes and astonish anyone seeing it.

Realistically I think a 16 tooth would be about the limit, and you might find that gearing would leave the bike a bit weak into headwinds and on slight slopes in top gear, necessitating more gear changing than usual. Consumption would rise again too.
.

Thanks for that flecc its very interesting. My current fitness level means i am yet to get the top gear on the torq to any real sustained cadence unless going down hill. would 18 teeth give me a similar gear set up to the torq. Ideally i'd want something slightly lower but not too much

edit: forgot to ask - would you need to fit a shorter chain?

cheers
Paul

 

[HarryB]

I wouldn't buy a second charger Hal, I'd just ride the 20 plus miles each day. The higher the quality of the battery and the better it's management, the less important the charge frequency becomes, the software protecting the battery well. Even at a high rate of drain on these bikes your journey is less than two thirds range, and on average nearer a half, so no problems with the 20 miles.

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I am glad you agree with me about that as it is a total pain unplugging and carrying a battery together with pannier bags etc.

Yes I am looking forward to not having a hub motor causing all that drag. The Torq motor is very noticeable when you first ride it after a normal bicycle. The Tongxin motor is pretty good and probably the best on the market but for me the drag will always ruin what would be "perfection" in an electric bike. I seem to be a convert without ever riding a 'panasonic' pedelec. I still find riding the Torq a hoot so I will wait and see what I think about the agattu

Once again thanks for the advice.

Hal

 

[flecc]

Pleasure Hal. You'll like the Kalkhoff just as much but in a different way, as it's also enjoyable, but relaxing in the way a Torq isn't.
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[simonbarnett]

Not being very technical, I think cadence is like rpm. But from memory Flecc, I think you recommended a change from the 22 tooth to 19 as the best compromise for a bit more speed at slight reduction of range? I forgot to ask 50C to do this so they'll love that...

 

[Erik]

Now that we are on to the subject of defying Panasonics intentions with this motor, wouldn't it be possible to forge the signal of "rider input" to make the motor give more than 130% of rider input?

Sensor value manipulation is the way the cheaper tuning boxes for turbo diesel cars work.