# RM charger



## Pockpaul (25 Jun 2019)

any good for touring? Or over priced? I was informed the batteries would probably need replacing after 4 years. This would be about £1600 on current costs. Seems a lot to me.


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## CXRAndy (26 Jun 2019)

I presume you mean this bike with dual batteries capability?
https://www.r-m.de/en-dk/models/charger/ £3-4000 models

Looks a rugged solid commuter, travel bike, Internal geared hub, hydraulic brakes guards and rack suspension even on saddle.

My on line research about battery longevity, is to rarely charge battery to more than 90%. Dont run battery down below 20%, keep battery in cool dry conditions. This can double or even triple the amount of charge cycles.


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## ebikeerwidnes (26 Jun 2019)

They do look expensive - but that's what happens if you go for something that has everything - and the best bit for everything. It seemed to have an amazing spec. 
the dual battery does (clearly) pretty much double the range - but (also clearly) mean that when it needs replacing it will cost twice as much. However, I assume that he battery in it uses top rated cells so it will last a lot longer than something using whatever chinese cells are cheapest at the time of manufacture. Therefore I would think that the standard of about 4 years would be pessimistic - if you look after the battery properly.
Also - bear in mind that batteries can be recelled cheaper than for a replacement - I had mine done recently and it was far cheaper even including an increase in capacity and using better cells. However, that isn't a Bosch battery - other people may have better info about that make.

So - yes it's expensive - but it looks like a good one. But you could get a cheapo ebike for half the price - with less gizmos and lower quality bits - but then it depends on how hard you want to push it - and how far you need to go on a single charge.


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## CXRAndy (26 Jun 2019)

It does look a very nice custom frame for the Bosch motor with all bells and whistle features. There are ways to making a normal bike into something quite special if you start with the correct base bike for your needs.

Im just embarking on making my wife's new shopper/commuter bike into a ebike. The base bike has IGH gears, disc brakes, rack and guards. I will be using a torque sensing crank drive motor. My budget is around £1200 for the whole setup inc bike cost. Im taking the B&M dynamo lights off her old bike with a newly laced front wheel. My calculations should give her 100 miles of moderate assist.


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## the snail (26 Jun 2019)

ebikeerwidnes said:


> Also - bear in mind that batteries can be recelled cheaper than for a replacement - I had mine done recently and it was far cheaper even including an increase in capacity and using better cells. However, that isn't a Bosch battery - other people may have better info about that make.


I think that is an issue with the bosch system, you can only use the Bosch battery, and it can't be re-celled - the BMS will detect the change and it won't work. Also two batteries would presumably take twice as long to recharge as one, which might be an issue if touring, although I would have thought one battery would give you a decent enough range? At the end of the day, this looks like a top-spec bike, but the cost of ownership is correspondingly high.


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## Pockpaul (26 Jun 2019)

Many thanks for your replies. I like the look of the bike and the spec. I guess with battery technology moving so fast at the moment who knows what the cost or size of the batteries will be in 4 years time. Maybe half the quoted price of today, and twice as powerful. I dont have any bike at the moment and not had a cycle since I was a lad ( now 63).


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## kynikos (26 Jun 2019)

R&M bikes are very well engineered and the Bosch system is one of the best. Battery life is excellent and I believe a recent test indicated 50K+ Km life, subject to the usual caveats.


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## Pale Rider (26 Jun 2019)

I have the previous model Charger with dual batteries and a Rohloff hub.

Nice bike, but a bit heavy even for an ebike.

There is software in the batteries - they each have their own performance data on the Bosch diagnostic check - which means recelling can be difficult.

I have an earlier shape battery from my first Bosch ebike which is about seven years old and still holding a decent amount of charge, even though the laws of physics say it must be declining.

Don't hold your breath for battery developments.

My old battery was first produced in 2010.

The latest batteries offer the same energy density and longevity, so that's pretty much no technological advance in nearly 10 years.

Every now and again, a laboratory comes up with improved battery chemistry that looks promising.

But such developments never get out of the prototype stage.

I suppose one might make it into production one day.


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## CXRAndy (26 Jun 2019)

I suppose the best battery technology is car EV batteries. I was watching a YT video which explains the difference between Tesla and most of the EV makers. They use slightly different chemistry to achieve different performance parameters. Tesla use individual cells upto(4000) which has some construction benefits aswell as temperature control

Tesla recommend 90% max charge for most occasion and not to drop below 20% for maximum life from battery packs


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## Pale Rider (27 Jun 2019)

As I understand it, the discharge properties for car cells are not best suited to ebikes.

There's no money in ebikes, all the development is concentrated on cars.

Energy density for the Tesla cells is not a great leap forward, meaning a notional pack for an ebike would still be big and heavy.

When Volta first designed his pile it was big and heavy.

Fast forward more than 200 years, and batteries are still big and heavy - that gives you an idea of the rate of progress.


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## theloafer (27 Jun 2019)

Pockpaul said:


> any good for touring? Or over priced? I was informed the batteries would probably need replacing after 4 years. This would be about £1600 on current costs. Seems a lot to me.



I have had my super charger gx-rohloff about 3 months and all I can say its a great bike and to me its worth every penny got from York at

https://ebiketips.road.cc/where-to-buy-ebikes/the-electric-transport-shop-york-182 ... call in and you will find john will give you all the info you need ..even let you have a test ride, found him very helpful and well informed ...also I think all duel battery models come with the fast charger's (well mine did)


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## Pockpaul (29 Jun 2019)

.. call in and you will find john will give you all the info you need ..even let you have a test ride, found him very helpful and well informed ...also I think all duel battery models come with the fast charger's (well mine did)

Yes have called in and found them very helpful. Although still not made my mind up if to go electric or conventional. I like technology and the thought of riding up hills with assistance. But would I feel move secure without having to rely on batteries. And would it feel more of an achievement without assistance? These are the questions I have yet to answer for myself.

A few years ago it would have much simpler!


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## theloafer (30 Jun 2019)

Yes have called in and found them very helpful. Although still not made my mind up if to go electric or conventional. I like technology and the thought of riding up hills with assistance. [/QUOTE] this is my ride info from last Sunday`s 90 mile easly enough power still in the tank for about 25 more the wonders of duel battery's 

https://www.strava.com/activities/2474855641


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