Shimano Nexus7 vs 8 speed

[echowind]

I have owned both the 7 speed and the premium 8 hub geared version. Can only one gear make so much difference? Let me tell you without doubt yes. The 7 speed has no direct drive and has a woolly stirring treacle feel about it, its also heavier with a much smaller gear range than the 8 speed version. Even the Sram 5 speed has a wider range. the 8 speed has better water resistance and roller bearings, direct drive is gear 5. I may be wrong but I thought Shimano discontinued the 7 speed a few years ago. I hope kalkhoff have specified the premium version for the pro_connect. you can tell the difference visually by a red line running around the hub. to make things more complicated theres now the Alfine disc brake version but I have no experience of this. I understand that gears are less important in regards to an electric bicycle, but anyway I would expect the better hub gears on bikes that cost so much..Halfords put the premium version on their carrera costing only £279 {discounted} and that was including the roller brakes.

 

[flecc]

There's seven speed and seven speed though, Shimano having changed the design some while ago and currently having two versions. There isn't the big difference you describe in between the current Nexus on the Agattu and the newer eight speed that's been chosen for the Pro-Connect. In fact the closeness of the eighth ratio to the seventh on the current eight has been criticised by some who've ridden it.

Shimano have never discontinued a seven , the four speed Nexus was the only one abandoned in recent years after a number of failures and much criticism of it having less range (184%) than the three speed.

On the Panasonic powered bikes the gear range is wasted anyway, since the top gear ratio is chosen for the maximum assist speed to be limited to 15 mph. The extra range and gears therefore just means ever lower low gears, again no use since a bike with electric assist doesn't need exceptionally low gears. I prefer a five or six speed on an e-bike since that comfortably covers the necessary speed range if the gear range is reasonable, say 225% or greater.
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[echowind]

I never knew there were two versions of the 7 speed. Do you know what improvements shimano made to the new 7speed?

 

[flecc]

No, I don't know the details, Shimano not seeming to make any announcement that I'm aware of. Maybe they acted in view of some criticisms, especially change problems since they've always liked to claim the slickest gearchanges, though not so concerned about efficiency.

I found the 7 speed on the Agattu to be excellent, very free running and slick changing after only an initial 140 miles in A to B's hands.
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[Colin Tate]

This is all slightly double dutch to me. But can I assume that the 7 speed nexus would be ok for a city ebike? I'm currently looking at bikes with both 7 and 8 speed - but don't want to be disadvantaged by say a 7 speed kalkhoff.

 

[anotherkiwi]

The 8 has better gear spacing and there is a "premium" version which has needle bearings instead of ordinary old bushings. In fact the premium version is actually the Alfine 8 speed without the disk brake mounting...

 

[flecc]

This is all slightly double dutch to me. But can I assume that the 7 speed nexus would be ok for a city ebike? I'm currently looking at bikes with both 7 and 8 speed - but don't want to be disadvantaged by say a 7 speed kalkhoff.

The 8 is more efficient than the 7 speed, but that isn't by a big factor and with power assistance on an e-bike it scarcely matters.

I didn't feel disadvantaged by the 7 speed when I reviewed the first Kalkhoff imported here in my hilly North Downs area over the period of a week.
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[Deleted member 4366]

Are you sure you want to buy a Kalkhoff? All sorts of motor problems reported. Some guys needed several repacement motors on the same bike.

 

[Colin Tate]

The 8 is more efficient than the 7 speed, but that isn't by a big factor and with power assistance on an e-bike it scarcely matters.

I didn't feel disadvantaged by the 7 speed when I reviewed the first Kalkhoff imported here in my hilly North Downs area over the period of a week.
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Thank you! That's very useful to know.

 

[Trevormonty]

Are you sure you want to buy a Kalkhoff? All sorts of motor problems reported. Some guys needed several repacement motors on the same bike.

The Bosch drive Kalhoff's are OK, its Impulse need to be wary of.