Improved re-branded Gruber system

[Miles]

http://www.vivax-assist.com/en/unternehmen/index.php

 

[Whiplash]

I think this system could be awesome but its power output is just too low. If it could do even 500a watts it would be very interesting but 200 is just not enough...

 

[amberwolf]

Ya know, I'd've said the same thing until today.
http://www.endless-sphere.com/forums/viewtopic.php?p=550415#p550415
Clutch on the Fusin broke leaving me with no motor, and I made it about a mile (of about 18) before I gave out. I managed to fix the clutch well enough to use 250-300W and a lot of pedalling, at about 12-13MPH, and made it all the way home on that. (well, half a mile from home before I overheated the motor, but that's another issue).

I would have even been happy with 150W at that point. :lol: Anything other than my screaming knees and exhausted body. Today definitely taught me a lesson about power and assist.

So even this little assist would be extremely helpful for many people.

 

[Solcar]

Amen bro AW.

 

[E-racer]

Someone needs to try a setup like this with a mamba monster or turnigy trackstar. The 1/8 scale rc inrunners are pretty ummm... power dense.

 

[crossbreak]

Looks very neat thx for posting
A big problem will be the noise the multistage planetary reduction will make.
The reduction from the gearbox to the pedal shaft is almost 1:1
I guess the motor will spin at 10 000 rpm to get this power. So The gearbox must gain a ratio of about 1:100
This setup is very similar to an accu drill (mostly two-stage planetary gearbox), but with three-stage gearbox. So it will sound like one fit into the frame, which is a great resonance body. it must sound horrible
The helical gearing at the final drive wont help, it just makes it durable

 

[Kraeuterbutter]

hi..
the Gruber Assist or now so called VIVAX is a complet different concept from the Bikes you use to build and drive here at endless-sphere...

here at Endless-Sphere you are only happy, with 500Watt, 800Watt, 1000Watt or even (lot) more
well: that all has not much to do with bicycling anymore

a normal, untrained person has about 100-120Watt average Poweroutput (about 80Watt for woman)

so: 100Watt (the Gruber has 200Watt electrical INPUT-Power, but max. 100Watt Outputpower)
so, this 100Watt Outputpower are about doubleing the average poweroutput from untrained people!
consider that for a moment.

for the Bike: i have driven the Gruber Assist 3.15version --> the motorunit weights only 900g (!) (less than an kg !) (2lb or 31,7oz)
and because it has only a maximum of 100Watt outputpower, a very small battery is enough too! for 1 hour FULL POWER the battery weights also less than 1000g (less than 2,2lb / less than 35oz)

AND: because the bike is so light, you don´t need to run the motor all time, you use it only when you need it uphill..
result: you can make a day-drip and this little less than 1kg-Battery is enough

Result: it is possible to build a mountainbike with Gruber-Assist which weights - INKLUDING the Battery AND the driveunit - only 10kg (!)
that are only 22.05lb or 350oz for the whole bike inkluding battery and driveunit !

i drove a Cannondale Caffein with a Gruber Assist 3.15 -- weight was about 14kg inkluding the battery

i have driven BOSCH-Bike, Panasonic-Bikes, Bafang with 800Watt, elfkw, Swiss-drive, BionX, and some more

but this Gruber-Assit was the only bike, i was not possible to say, it was an electric bike when the motor was off..
on all the other bikes you feel the weight in more or less ways..
resulting, that you normaly don´t wana drive them with motor turned off

but the Gruber driveunit is that light, that you don´t feel the weight - so best bicycling-experience so far


so: for the news:
last year the Version 3.15 was introduced..
this version had an 3-stage gearing
(the 100Watt are most likey not because the motor is that weak, but much more torque would kill the little gearings, remember how little space there is inside the tube)

here a sound-example...
http://www.youtube.com/watch?v=qQG9FsfmxjY
[youtube]http://www.youtube.com/watch?v=qQG9FsfmxjY[/youtube]
also this was already the 3db (50%) quieter version, it was still ... too load in my ears..


her now the new 4.0 version, now called VIVAX:
http://www.youtube.com/watch?v=CgbCa2v2a9U
[youtube]http://www.youtube.com/watch?v=CgbCa2v2a9U[/youtube]
impressive improvement
(they went from 3stage to 2stage-gearing)

on both videos: its a 11% slope which the woman is going up very easily

 

[Hillhater]

Very impressive, but you have to question the durability of such small gear trains, and I am guessing the latest version has not reduced the cost ?

 

[StudEbiker]

Ya know, I'd've said the same thing until today.
http://www.endless-sphere.com/forums/viewtopic.php?p=550415#p550415
Clutch on the Fusin broke leaving me with no motor, and I made it about a mile (of about 18) before I gave out. I managed to fix the clutch well enough to use 250-300W and a lot of pedalling, at about 12-13MPH, and made it all the way home on that. (well, half a mile from home before I overheated the motor, but that's another issue).

I would have even been happy with 150W at that point. :lol: Anything other than my screaming knees and exhausted body. Today definitely taught me a lesson about power and assist.

So even this little assist would be extremely helpful for many people.

So true. In the first few rides of the Bike E it seemed to feel underpowered. Until one night I shorted phase wires and had to pedal it all the way home. Fortunately I was only about 5 miles from home (not 18! ), but it really gave me an appreciation of just how much power was coming from the battery.

 

[SamTexas]

here at Endless-Sphere you are only happy, with 500Watt, 800Watt, 1000Watt or even (lot) more
well: that all has not much to do with bicycling anymore
a normal, untrained person has about 100-120Watt average Poweroutput (about 80Watt for woman)

Well said. For me, the difference between 13mph and 17mph average on a 100 mile run is humongous. The 100W added by the motor makes the ride an even better joy, and still leaves me with some energy at the end to celebrate.

so: 100Watt (the Gruber has 200Watt electrical INPUT-Power, but max. 100Watt Outputpower)

I hope you're wrong here. 50% efficiency for a product that has been around for years is simply not acceptable, especially when investment cost is taken into account. If I were to buy such an expensive systems, I would expect better efficiency, much much better.

 

[Kraeuterbutter]

I hope you're wrong here. 50% efficiency for a product that has been around for years is simply not acceptable, especially when investment cost is taken into account. If I were to buy such an expensive systems, I would expect better efficiency, much much better.

no, unfortunatly this is true (at least for the older versions of the Drivetrain)
50-60% efficience

but you have to consider:

a fast -spinning Motor
+ a 3-stage Gearing
+ the 90° Gearing at the bottom
+ the Gears of the bikes itself

all together costs efficience... thats the downside of an Motor with only 30mm diameter geared down to 60-90rpm
maybe the ne one is a little more efficience, because one gearing-stage was eliminated - but i don´t bet so

so, yes: a directdrive-motor or a bafang with the big gears and slow rpm runs more efficient (until it comes to real steep hills and slow speed, where the eta can go down to 25-30% aswell)