Hello - newbie looking for opinions!

[Skeeter]

Hello all, I was pointed in the direction by a e-bike fan and I have a few questions.

I'm in the middle of fixing up an oldie, and I've recently warmed to the idea of adding a conversion kit. But this post isn't about 'which kit is best' so relax...

Breaking the speed record does not concern me much but rather the central question that concerns all electric vehicles does - range. I recently read a post on this forum where someone claimed 100+ miles. That seems surprisingly high. If I could have that I would be happy.

I have heard the opinion that pedal-assist is better for range than throttle control and that CD is the best all-round choice but since I would be largely sticking to tarmac I am leaning toward rear-wheel drive.

So (I assume) its all about the battery. I could buy one of many kits which are supplied without one, so if I did what (lithium) battery would be an ideal choice?

I freely admit I don't really understand why 48v may (or may not?) be more betterer (by what scale of reckoning?). Nor do I have much of an idea of the ideal min/max Ah capacity I should be aiming for (another poorly-formed assumption is that more in both categories is better), or even what would be best on a capacity vs cost analysis.

Any wisdom offered will be gladly received and obsessed over for ages, I expect. Thanks in advance.

Skeeter.

 

[vfr400]

48v is better because you get more torque for the same current, which means that you can use a small controller and nothing will over-heat. Also the lower current gives the battery an easier time. I would always recommend 48v for a hub motor unless you want a light weight low power system.

Some of your research seems to be a bit dubious. The problem is always to know whether what you're reading is from an authoritative source. Often people make up theories based on their paradigms rather than actual knowledge or test data.

Range is simple. The bigger the battery you have, the more it weighs and the further you can go. What anybody else gets from their bike, battery, sensor, motor or control system is completely irrelevant. Some bikes are more efficient than others. I'm sure you're aware that, apart from comfort, you can ride a road bike further and faster than an MTB. That still stands if you put the same electric kit on each of them. There is very little difference in the efficiency of different electrical systems, but the way you use them can make a big difference.

I can make a general statement about range. Anecdotally, from many years on this forum, I would say that an average unfit rider on an average bike riding in an area that is medium hilly, pedalling comfortably at an average speed around 12 mph will achieve around 30 miles from a 36v 10Ah battery, i.e. a consumption of around 10Wh per mile.

 

[Skeeter]

Hi VFR400.

My 'research' amounts to watching a few youtube vids, grazing some ebay offers, and reading through some posts on a different forum where everybody disagrees with each other as a matter of principle. So your post seems to me to be hugely informative.

One question if I may - does it follow that a 36v 30ah battery would give approximately a 90 mile range, or does the law of diminishing returns hold true?

I take your point about comfort and road bikes; this may very well not be the only project!

Many thanks

Skeeter

 

[soundwave]

Hi VFR400.

My 'research' amounts to watching a few youtube vids, grazing some ebay offers, and reading through some posts on a different forum where everybody disagrees with each other as a matter of principle. So your post seems to me to be hugely informative.

One question if I may - does it follow that a 36v 30ah battery would give approximately a 90 mile range, or does the law of diminishing returns hold true?

I take your point about comfort and road bikes; this may very well not be the only project!

Many thanks

Skeeter

it depends how fast you go and how many hills you need to climb and what mode you use and how much you can put towards that with peddling.


my 500w 13.4ah bat can do 50 miles if i use the lower settings out with m8s on a long bike ride but if i hammer it in turbo with a dongle the range will be 25 miles or less on the flat with the speed limit removed.

 

[Nealh]

36v 30ah battery is 1080 wh for a rider who can manage 10wh per mile or even less then about 100 miles is possible, an unfit plodder who uses higher assist level it will be at least half the range. One simply can't put an actual range figure down on paper as there are to many variables involved. Terrain, bike style & weight, rider weight fitness and weather conditions just for a start.
30ah is one big heavy battery.

 

[vfr400]

A 30AH battery would weigh about 6kg, which would be too big and heavy for a bicycle.

Why do you need so much range? You'd have to be someone special to do 90 miles in a day on an electric bike.

 

[Kevin fenwick]

Hi I have a 2012 giant hybrid escape 1 electric bike, my problem is I have the bike in storage for a year or so. I charged the battery back up and took it for a run, battery was working then it just cut out pressed power again came on rode on and it cut out again. battery is holding its charge,any ideas what the problem is. concearned newbie

 

[Skeeter]

Thanks all for the input. I'm taking it all on board.

I have two main desires from an e-bike:

1. Go to the supermarket. Haul lots of shopping back home. Round trip: 10 miles? This seems easily achievable.
2. I live about 30 miles from London. So I would like to be able to make the return journey. Sometimes, not every day.

If I could do it then this would constitute a 'car replacement' - about 80% of my need for a car anyway. But I can see from your comments that my expectations here are unrealistic.

Another area of interest - I would like to spend the least amount on my home-build - don't we all. I am thinking of a max £200 spend on a rear wheel unit in order to have as much left in the kitty for a decent battery. Please feel free to criticise this notion. I can take it.

Thanks again.

Skeeter

 

[vfr400]

Hi I have a 2012 giant hybrid escape 1 electric bike, my problem is I have the bike in storage for a year or so. I charged the battery back up and took it for a run, battery was working then it just cut out pressed power again came on rode on and it cut out again. battery is holding its charge,any ideas what the problem is. concearned newbie

Start a new thread of your own otherwise everyone is going to get confused. This thread is about a guy that wants to buy a conversion kit.

 

[vfr400]

Thanks all for the input. I'm taking it all on board.

I have two main desires from an e-bike:

1. Go to the supermarket. Haul lots of shopping back home. Round trip: 10 miles? This seems easily achievable.
2. I live about 30 miles from London. So I would like to be able to make the return journey. Sometimes, not every day.

If I could do it then this would constitute a 'car replacement' - about 80% of my need for a car anyway. But I can see from your comments that my expectations here are unrealistic.

Another area of interest - I would like to spend the least amount on my home-build - don't we all. I am thinking of a max £200 spend on a rear wheel unit in order to have as much left in the kitty for a decent battery. Please feel free to criticise this notion. I can take it.

Thanks again.

Skeeter

Some cheap kits are horrible. best to show us what you're going to buy before placing any orders. Look for one with an LCD control panel. Avoid the big 500W or 1000w direct drive motors.

 

[Skeeter]

Thanks VFR, I will do exactly that - but tomorrow. Also I found your comment about folding bikes to be most apt and also very funny. I have considered this (a bit).

Ps I think your choice of motorbike to be very cool. I always wanted one of those. Big Honda fan here.

 

[sjpt]

The Bosch Range assistant gives a good idea of range on most bikes, not just Bosch. https://www.bosch-ebike.com/en/service/range-assistant/ You need to factor in battery size (wH) if you don't have one of their standard sizes, and do a bit of interpretation about motor type and assist settings.

You'll never get an exact answer, but it gives a very good idea about how different factors affect range. You will find that typical really light setting (flat, lowest assist, best road, best tyres, etc etc) will give around 100 miles for a 400wH battery. Play with the settings a bit and it will quickly drop to 33 miles (1/3 original) even with 'tour' level of assist in realistic conditions, and lower still with sport/turbo.

 

[Nealh]

For a touring /day out rider then 100 miles range isn't improbable though you need to be a dedicated rider or have a comfy bike set up to do this.
I go out for day rides and just over 100 miles is about my longest trip.
A 36v down tube 14.5ah reserve/ get me home battery and the main battery a 48v 20ah one on the rear rack. I try not to deep discharge packs and usually swap over at 3.6v per cell group, should I encounter windy conditions then I have a little in reserve should I use too much of the available wh.

My rear rack is low (approx. 1.5" max above the wheel and is as far forward as I can get it, this improves the heavier bike weight/handling on a ride. If one fits a rack and sets it too high or far back over the wheel then handling will be tail happy. My pack is 3.75kg and ride handling isn't affected by the extra weight, I use this bike on all trails rough or smooth on the N & S Downs. I don't keep to just the nice trails and it goes down many tracks and across fields/routes that not many probably even take their mtb's.

 

[Skeeter]

Ok well misconceptions altered. Paradigms shifted. Thinking about mopeds...

Re VFR's last comment, I'm looking at ebay offerings for you all to criticise (and I welcome the crit). I'll post a link or two shortly.

One thing that bothers me is the recommendation to find a kit with a display. Why is this so great? I can't help but feel that will be the first thing to get nicked if it can't be removed by the user (and the ones I have seen advertised don't look like they can).

ETA is there a rear wheel kit anybody would recommend?

 

[Skeeter]

Just noticed the section discussing which kit...maybe everything I need to know is there. Here's one that might do me though, any thoughts?

https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2047675.m570.l1313&_nkw=36V350W+26"+Rear+Motor+fit+Cassette+E-bike+Hub+Motor+Conversion+Kit+Black&_sacat=0

 

[vfr400]

Kits with no control panel/display only have one level of pedal assist - maximum! That's not very convenient.

The kit you linked to is OK, and not bad for the money. The main work in fitting it is to to install two rivnuts in your downtube for that type of battery mount. The fixing positions are at the top end, so they won't line up with your bottle fixing screws. Also, it's advisable to fit a screw in the bottom end of the mount, which means disassembling the mount and drilling it. That's not too difficult when you have a separate controller, but that kit has the integrated one, which doesn't leave much room for the screw. As long as you're a practical person and used to fabricating things, that's all pretty straight forward.

I prefer this type of battery because the fixing screws normally line up with the bottle fixing screws. I still add a third rivnut to the frame for security:

 

[RobF]

Ok well misconceptions altered. Paradigms shifted. Thinking about mopeds...

Re VFR's last comment, I'm looking at ebay offerings for you all to criticise (and I welcome the crit). I'll post a link or two shortly.

One thing that bothers me is the recommendation to find a kit with a display. Why is this so great? I can't help but feel that will be the first thing to get nicked if it can't be removed by the user (and the ones I have seen advertised don't look like they can).

ETA is there a rear wheel kit anybody would recommend?

I suspect the LCD display comment relates to kits with LCD displays being generally better than those with other types.

You will struggle to get a battery that will reliably do the 60 mile trip to London, so I think the only answer is to carry a spare for longer rides.

My bike has a twin battery set up, and I regularly do 100+ mile day rides on it.

Regrettably, I have to carry a third battery for those rides because I cannot reliably squeeze 50 miles out of one battery, given all the variables.

 

[Skeeter]

Kits with no control panel/display only have one level of pedal assist - maximum! That's not very convenient.

The kit you linked to is OK, and not bad for the money. The main work in fitting it is to to install two rivnuts in your downtube for that type of battery mount. The fixing positions are at the top end, so they won't line up with your bottle fixing screws. Also, it's advisable to fit a screw in the bottom end of the mount, which means disassembling the mount and drilling it. That's not too difficult when you have a separate controller, but that kit has the integrated one, which doesn't leave much room for the screw. As long as you're a practical person and used to fabricating things, that's all pretty straight forward.

I prefer this type of battery because the fixing screws normally line up with the bottle fixing screws. I still add a third rivnut to the frame for security:

Drill the frame for rivnuts! Not keen. I've never used a rivnut, only seen pictures, fairly hands-on, but drilling the frame is not a welcome prospect. I've noticed most of these batteries come with a locking system which all seem a bit crap. Do you habitually leave the battery on the frame when the bike is unattended?

 

[Skeeter]

Another really important point: this is another kit from the same mob, much the same, but sans battery and thus cheaper.

36V350W 26" Rear Motor fit for Cassette Electric Bicycle Conversion Kit Black | eBay

Find many great new & used options and get the best deals for 36V350W 26" Rear Motor fit for Cassette Electric Bicycle Conversion Kit Black at the best online prices at eBay! Free delivery for many products!

www.ebay.co.uk

Is it reasonable to assume someone else's battery will have the same connectors?

 

[vfr400]

Another really important point: this is another kit from the same mob, much the same, but sans battery and thus cheaper.

36V350W 26" Rear Motor fit for Cassette Electric Bicycle Conversion Kit Black | eBay

Find many great new & used options and get the best deals for 36V350W 26" Rear Motor fit for Cassette Electric Bicycle Conversion Kit Black at the best online prices at eBay! Free delivery for many products!

www.ebay.co.uk

Is it reasonable to assume someone else's battery will have the same connectors?

You don't normally get connectors with a battery. If you did, there's virtually no chance that they would match any kit.