Livall's venture, their Pikaboost ?

[Ocsid]

Possibly I am running well behind the curve, but today I came across this venture that Livall are into.
"Pikaboost"

Brings back visions of a neighbour in the early 50s with their petrol powered device over their rear wheel.
At least now the awful two stroke's pollution has gone, but what are the thoughts of our e-bike experts here on this modern take on the concept?

I have resisted being an investor, for me that bit was easy enough!

 

[flecc]

Ever since the Zap Kit of decades ago there have been large numbers of these addons of "new" friction drive kits. Even our own Sinclair came out with useless variants for either front or rear wheel drive.

They all went the same way, into oblivion, due to their many disadvantages.
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[guerney]

Fully funded with "£596,799 pledged of £21,557 goal".

A mudgaurd attached underneath, would spoil it's sleek look - there are no mudguards on any of the bikes in the promo video. Easy installation, wet muddy legs.

LIVALL PikaBoost: E-bike Conversion Kit

30 seconds tool-free installation. Fits all bike. Intelligent assistance. Sold at an honest price.

www.kickstarter.com

 

[Nealh]

Revos in Bristol are one the exceptions , there friction kit is still going strong afaik and my one is still going well.
The revos isn't an all-in one bolt on seat post device and utilises a seperate down tube battery.

 

[guerney]

Do any friction motors have multiple switchable internal gears? I'd be interested, if they had at least 6 to tackle hills. The idea of easily being able to take the entire e of an ebike away with me, after locking the bike to a bikestand, is appealing.

 

[Nealh]

Not afaik, they are all generally based on a small RC type bldc motor.

 

[flecc]

Do any friction motors have multiple switchable internal gears? I'd be interested, if they had at least 6 to tackle hills. The idea of easily being able to take the entire e of an ebike away with me, after locking the bike to a bikestand, is appealing.

None of them ever have had. It's only riders that need lots of gears, given electric motor torque, only two gears are needed to cover the legal and practical assist speed range of 4 to 15.5 mph.

Also drive slip and resulting tyre wear is a potential problem with friction drive, especially in wet weather, and that would be exacerbated in lower gears creating more torque.

The two gears covering the range are present in two hub motors so far, the Xionda and the SRAM Automatix.
.

 

[Nealh]

My first tyre got chewed up with 500 miles, it was a wtb riddler a slightly knobbly tyre. I found the answer was to use a knobbly tyre with a smooth raised centre section and the specialiased 2bliss pathfinder pro has been great, tyre wear is minimal and the raised centre section is still good.

In the 700c/650b tyre sizes I find tyres other then scwalbe much better to my liking, for non friction drive I mainly use the Panaracer SK gravel king a nice small block tyre and wtb's.

 

[Bonzo Banana]

These don't appeal to me at all, limited and expensive for what they are and highly proprietary. The best feature is they can be moved to different bikes easily so any bike you have I guess can be quickly configured as an ebike. Hopefully a cheaper more generic version will come out. Perhaps a scooter type wheel design. I would of thought a mass produced version could easily sell sub £200 at retail.

 

[guerney]

If it was wider and had two extra wheels connected to the drive wheel either side, plus a couple of wheels at the front and a telescopic or fold out handle, and if the main body could slide out to form a platform... it could transform into a dangerous e-scooter in it's spare time - a wider body could accommodate a larger battery. I'd like to see extra pressure applied to the wheel for very steep hills, via hydraulic or the tightening of a spring, applied automatically or manually as required - for wet hills climbs, surely it can't be all that difficult to add a auto-slip detection system?

 

[flecc]

These don't appeal to me at all, limited and expensive for what they are and highly proprietary. The best feature is they can be moved to different bikes easily so any bike you have I guess can be quickly configured as an ebike. Hopefully a cheaper more generic version will come out. Perhaps a scooter type wheel design. I would of thought a mass produced version could easily sell sub £200 at retail.

Agreed, and we have had a number of much cheaper friction drive kits over the years. But friction drive really only suits the light assistance market and that is small, hence most of them failing.

True even without friction drive. US company Schwinn had a brave try in the light assistance market with a Nano hub motored model using a Toshiba SCiB battery, but that soon vanished. Our own Cytronex company tried hard using a Nano based kit fitted to high quality ultra light bikes but they are no more.

The bulk of the market seems to be for more power/torque/hill climb ability/range than friction drive can accommodate in all weathers. It's why friction drive kits will never compete with the likes of Bafang and Bosch and history shows that most fail in the market very quickly.
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[StuartsProjects]

Looks like the battery pack is super easy for users to take apart and replace worn cells, a bit like replacing batteries in a radio etc.

Has this been done before on an eBike battery ?

 

[guerney]

Looks like the battery pack is super easy for users to take apart and replace worn cells, a bit like replacing batteries in a radio etc.

I bet some users will replace with mis-matched cells - I wonder how that'll go?

 

[flecc]

Looks like the battery pack is super easy for users to take apart and replace worn cells, a bit like replacing batteries in a radio etc.

Has this been done before on an eBike battery ?

Sinclair's two front or rear Zeta e-bike kits used D cells that were easily use replaceable. They were low powered though so didn't last long in the market.

The trouble for most e-bike motors is the current is often too high for surface battery contacts. They need to be welded or at least soldered to avoid contact burn. Even the contact blades on e-bikes suffer contact burn as this photo shows:

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[StuartsProjects]

I bet some users will replace with mis-matched cells - I wonder how that'll go?

You would imagine not very well.

But if the basic idea, some sort of surface contact, is flawed then you wonder how its got past even the most basic of tests.

 

[guerney]

You would imagine not very well.

But if the basic idea, some sort of surface contact, is flawed then you wonder how its got past even the most basic of tests.

Like Vruzend kits perhaps: screw-on contacts? They now have a decent budget for R&D.

NEW! Vruzend V4 20A Copper DIY Solderless 18650 Battery Holder No Spot Weld UK

Description The VRUZEND V4 is our high power battery building kit. The caps are a complete redesign intended to eliminate cracking and the cells drop into the holder just like a battery into a torch. The bus bars, clamps and nuts are made of high grade copper for highest conductivity and nickel...

vruzend.co.uk

 

[StuartsProjects]

Like Vruzend kits perhaps: screw-on contacts? They now have a decent budget for R&D.

Watch the Video, no evidence at all of screw-on contacts. The batteries are shown just being put in the holder\seperator and the top clipped on. No screws visible.

And the clip on top does suggest something else is missing .........

 

[peterjd]

Agreed, and we have had a number of much cheaper friction drive kits over the years. But friction drive really only suits the light assistance market and that is small, hence most of them failing.

True even without friction drive. US company Schwinn had a brave try in the light assistance market with a Nano hub motored model using a Toshiba SCiB battery, but that soon vanished. Our own Cytronex company tried hard using a Nano based kit fitted to high quality ultra light bikes but they are no more.

The bulk of the market seems to be for more power/torque/hill climb ability/range than friction drive can accommodate in all weathers. It's why friction drive kits will never compete with the likes of Bafang and Bosch and history shows that most fail in the market very quickly.
.

I think friction or similar direct drive to the tyre or rim has a place in the current market. I am quite satisfied with my current options which is my original old touring bike fitted with a much visually modified Swytch kit, the front powered wheel and a Yose battery on the rear rack. The weight distribution is not bad and it manages to give adequate assist on all the local hills. For holiday use on the flat and in the dry I have a late model Bickerton folder fitted with a surplus Chinese friction drive, RC type controller with throttle and braking sensors, and a Bosch type lawnmower battery on its rack. So not currently legal (but I'm working on it) and quite fiddly in acheiving 'optimum' tyre contact. When set up ok it is quite fun to use. The cost of the "e-Bickerton" was about £70 for the bike some years ago and perhaps another £100 for the various ebike bits. If I live in suitablly fit state for a few more years I might invest in a new ebike/pedelec if the technology advances somewhat to fit my then needs. Peter

 

[guerney]

Watch the Video, no evidence at all of screw-on contacts. The batteries are shown just being put in the holder\seperator and the top clipped on. No screws visible.

And the clip on top does suggest something else is missing .........

A working product isn't necessary for the video, I think the device depicted is a model, and the uphill shots, cruise control etc, are simulated using video footage from after the cyclist stops pedalling, and judging by the angles of some of the trees in the background, they've tilted the camera or footage to make some roads look like they're on hills.

This friction drive's "Cruise mode", which propels the bike maintaining a constant speed without the user required to pedal, makes it UK illegal surely?

 

[StuartsProjects]

A working product isn't necessary for the video

If the way the batteries are 'replaced' in the Video is not accurate, then in the UK at least that would likely be missleading advertising.

But the other obvious bit, how would the connections for a BMS work ?

Looks like a 6 sets of 3 in parallel ..............