DIY electric mountain bike

[President Merkin]

Usual words of caution if you're contemplating buying off brand Li-On batteries of questionable provenance. Not saying don't do it but do think about storage.

https://www.bbc.co.uk/news/uk-england-london-65088...

[bennno]

tommobot said:

Ok, sorry for the constant barage of questions.

I'm not moving towards the rear hub motor I think..

https://www.yosepower.co.uk/products/36v15-6ah-dow...

36V15.6Ah HL Plus Li-ion E-bike Battery with 5 Pins Plug Not Round Pins and XT60 Adapter

Along with this 500w kit here;

https://kirbebike.com/diy-conversion-kits/kirbebik...

This would be £520 ish and would get me a decent rear hub motor and decent battery as far as I can see.

Thoughts please?

My thoughts are the police should be clamping down on home made electric bikes, so many are not speed regulated and have had the pedal sensors disconnected - seems like its a way of doing 40-50mph (often on pavements) without any training or insurance....

[ARHarh]

I bought my battery from https://batteryempire.co.uk/146-batteries-for-ebik... good service and felt a bit safer than generic Chinese stuff. Been a good battery for the last 2 years and hardly ever burnt my house down.

[wpa1975]

bennno said:

tommobot said:

Ok, sorry for the constant barage of questions.

I'm not moving towards the rear hub motor I think..

https://www.yosepower.co.uk/products/36v15-6ah-dow...

36V15.6Ah HL Plus Li-ion E-bike Battery with 5 Pins Plug Not Round Pins and XT60 Adapter

Along with this 500w kit here;

https://kirbebike.com/diy-conversion-kits/kirbebik...

This would be £520 ish and would get me a decent rear hub motor and decent battery as far as I can see.

Thoughts please?

My thoughts are the police should be clamping down on home made electric bikes, so many are not speed regulated and have had the pedal sensors disconnected - seems like its a way of doing 40-50mph (often on pavements) without any training or insurance....

Exactly plus nobody seems to care that you putting a massive additional load and strain on frames that were never designed for it.

[Senex]

tommobot said:

You'll be taking a chance.

Will all the bits work together?

Will I get any after-sales service?

Will I burn my house down?

Will I break any bones when I fall off?

Will it get seized by the police?

.....but on the other hand, if you have access to private land *cough*, it looks like a lot of fun.

[President Merkin]

wpa1975 said:

Exactly plus nobody seems to care that you putting a massive additional load and strain on frames that were never designed for it.

That is with respect, pearl clutching nonsense.

[ruwokeenuff]

Senex said:

tommobot said:

You'll be taking a chance.

Will all the bits work together?

Will I get any after-sales service?

Will I burn my house down?

Will I break any bones when I fall off?

Will it get seized by the police?

.....but on the other hand, if you have access to private land *cough*, it looks like a lot of fun.

best for some to just stay in bed I think!!

Edited by ruwokeenuff on Thursday 30th March 14:00

[Driver101]

bennno said:

tommobot said:

Ok, sorry for the constant barage of questions.

I'm not moving towards the rear hub motor I think..

https://www.yosepower.co.uk/products/36v15-6ah-dow...

36V15.6Ah HL Plus Li-ion E-bike Battery with 5 Pins Plug Not Round Pins and XT60 Adapter

Along with this 500w kit here;

https://kirbebike.com/diy-conversion-kits/kirbebik...

This would be £520 ish and would get me a decent rear hub motor and decent battery as far as I can see.

Thoughts please?

My thoughts are the police should be clamping down on home made electric bikes, so many are not speed regulated and have had the pedal sensors disconnected - seems like its a way of doing 40-50mph (often on pavements) without any training or insurance....

Often doing 40-50mph on pavements? I've yet to see a single one. On the roads I've seen about 2.

None of the kits linked on this thread will propel a bike to anywhere near 40-50mph.

[bennno]

Driver101 said:

Often doing 40-50mph on pavements? I've yet to see a single one. On the roads I've seen about 2.

None of the kits linked on this thread will propel a bike to anywhere near 40-50mph.

The one in the link below is 500-750w and 'will propel a rider to 30mph uphill', note it says off road use only as its otherwise entirely illegal to use on any public road or footpath. Not that that stops deliveroo riders etc....

[Richtea1970]

bennno said:

Driver101 said:

Often doing 40-50mph on pavements? I've yet to see a single one. On the roads I've seen about 2.

None of the kits linked on this thread will propel a bike to anywhere near 40-50mph.

The one in the link below is 500-750w and 'will propel a rider to 30mph uphill', note it says off road use only as its otherwise entirely illegal to use on any public road or footpath. Not that that stops deliveroo riders etc....

With a 500/750w you've got zero chance of going 30mph uphill, that's just the usual false advertising. The kit is illegal but don't think you'll be flying around at anywhere near moped speeds.

[ARHarh]

Mine has 1000w 48v, and it will hit 25mph on the flat, a slight hill will slow it to 20mph, and a 25% gradient will have it down to walking pace. Never quite sure of the figures you hear banded about. The are probably set to KPH and cant realise MPH is not the same. I sometimes come across other electric bike riders and tend to cycle past them so most aren't getting anywhere close to 30 mph.

[bennno]

ARHarh said:

Mine has 1000w 48v, and it will hit 25mph on the flat, a slight hill will slow it to 20mph, and a 25% gradient will have it down to walking pace. Never quite sure of the figures you hear banded about. The are probably set to KPH and cant realise MPH is not the same. I sometimes come across other electric bike riders and tend to cycle past them so most aren't getting anywhere close to 30 mph.

You'll be cycling past as yours as described is illegal as it has 4x the 250w maximum in the uk and doesn't cut out at the maximum of 15.5mph.

[gmaz]

Richtea1970 said:

bennno said:

Driver101 said:

Often doing 40-50mph on pavements? I've yet to see a single one. On the roads I've seen about 2.

None of the kits linked on this thread will propel a bike to anywhere near 40-50mph.

The one in the link below is 500-750w and 'will propel a rider to 30mph uphill', note it says off road use only as its otherwise entirely illegal to use on any public road or footpath. Not that that stops deliveroo riders etc....

With a 500/750w you've got zero chance of going 30mph uphill, that's just the usual false advertising. The kit is illegal but don't think you'll be flying around at anywhere near moped speeds.

I built a 36v/750w bike and it can get to about 25mph on the flat. I am 17st though.

[Driver101]

bennno said:

Driver101 said:

Often doing 40-50mph on pavements? I've yet to see a single one. On the roads I've seen about 2.

None of the kits linked on this thread will propel a bike to anywhere near 40-50mph.

The one in the link below is 500-750w and 'will propel a rider to 30mph uphill', note it says off road use only as its otherwise entirely illegal to use on any public road or footpath. Not that that stops deliveroo riders etc....

We've gone from 40-50mph down to 30mph.

They suggest it'll do 30mph which is entirely possible. I regularly manage over 30mph on a normal bike. It won't manage 30mph on a flat and it won't get near 30mph up a hill even with a good bike with a light rider.

The amount of ebikes doing 40-50mph are few and far between. Suggesting it happens often and on pavements is pure exaggeration.

[Driver101]

bennno said:

You'll be cycling past as yours as described is illegal as it has 4x the 250w maximum in the uk and doesn't cut out at the maximum of 15.5mph.

Some of the 250w legal bikes put out 600w maximum. They are quicker than many of the higher powered illegal bikes.

Edited by Driver101 on Thursday 30th March 16:28

[Senex]

ARHarh said:

Mine has 1000w 48v, and it will hit 25mph on the flat, a slight hill will slow it to 20mph, and a 25% gradient will have it down to walking pace. Never quite sure of the figures you hear banded about. The are probably set to KPH and cant realise MPH is not the same. I sometimes come across other electric bike riders and tend to cycle past them so most aren't getting anywhere close to 30 mph.

So that will be one of those direct drive motors? Black and the size of a dinner plate?

Fast on the flat but no good at hill climbing.

A geared hub motor will always beat it up hills.

[ARHarh]

All those comments are right as I know it's not legal. and I know a geared motor will get up a hill easier. But what I was saying is 30 mph is not really going to.happen unless you are pushing a lot of kws.

[ruwokeenuff]

bennno said:

You'll be cycling past as yours as described is illegal as it has 4x the 250w maximum in the uk and doesn't cut out at the maximum of 15.5mph.

I did 71 on the motorway yesterday...

[tommobot]

Thanks for the comments guys, just regarding the power of the bike or the hub kits.

If i'm doing 40 down a pavement then I can see the issues, but an assisted 15 or 20mph along country rodes..

Surely its the same as having a Mclaren with 700bhp and the ability to go 200mph but as long as you stray within the limits (ish) its ok?

[ARHarh]

The answer is don't ride like a dick and chances are you will be fine. As in most things in life.