Gruber Assist: 100W in the seat tube

[VSkudarnov]

I imagine that it must result in quite a natural bike riding experience rather than a half motorbike that the throttle setups give.
Hows it behave at say starting to pedal away from an intersection? is it a smooth application of assist power of jerky?

There are not that many traffic lights in the mountains ) So I usually turn it when I have some speed already. But even from the start, it starts very smoothly and turns off if there is any obstruction/cadence lower than normal.

100W is like strong wind from the back or like pedalling on the flat while going on a 10% hill. And that's with MTB tires (I am going to try it with semi- or slicks). Very natural pedalling.

I have another 360W Cyclone to compare:
- Cyclone is much more noise, but quicker uphill.
- 360W is excessive, 200-250W at the right rpms is enough.
- Gruber should have a much better range.
- with Gruber, I can use all 3 front chainrings
- I can pedal without assistance without stupid freewheel clicks and 3 kilo ballast.
- Gruber is expensive but you get what you paid for - a true lightweight cross-country MTB with a hidden "cheat"

 

[Ricky_nz]

But even from the start, it starts very smoothly and turns off if there is any obstruction/cadence lower than normal.
100W is like strong wind from the back or like pedalling on the flat while going on a 10% hill. Very natural pedalling.
I have another 360W Cyclone to compare:

Thanks, good to have a comparison to a more common setup.
The elation 300W kit I have is essentially a 360W cyclone (same motor). Agree with the noise and the freewheel clicks etc ( reoiling the plantary helps with the gearbox noise).
Sounds like the gruber is a nice fit for those who like pedling

 

[recumpence]

I must say, there is an application for all drive systems. Personally, I normally use 300 watts from my drives for cruising. But, I also like being able to pull 8,000+ watts when I want to. :wink:

Anyway, I think the perfect application for this is the individual that just needs some help up the hills to open up a new world of cycling he or she would never otherwise experience.

I have a tiny 180 watt electric scooter for my boys. It pulls me along just fine at 8 to 10mph. That is similar to what this assist would do.

I agree that 100 watts is pretty weak. But, as I (and others) have already stated, for its intended purpose, this system seems just fine.

Matt

 

[VSkudarnov]

Brief update:

- got my HK order with 8 4S batteries. Shit, they are small and light!
- put 4 into the saddle bag for 10ah, 30v.
- did the usual evening route (about 10km long, 500m uphill) - very impressed: Gruber does not give you rest - you still need to pedal. But it helps you to keep a steady cadence (max. 80rpm, I think). It is quite low for me - but I did not lose any breath on the uphill, and the hill ended surprisingly quickly.

Also, it teach you to pedal correctly (clipped) - pushing through the complete cycle - without burst pushes.
It is not superfast, but perfect tool for aerobic training!

 

[kfong]

Sounds like a great setup. One of the reasons I went with a low speed high torque bmc motor. At 40volts my maxspeed is 21mph. At this speed I can realistically help with pedaling. I can use all 27 gears with my setup; the low gears have been very useful when I'm out of power. I pedal as much as I can to prolong my trail rides and usually push the packs to the end, leaving me to pedal the last few miles without power. I set a personal best yesterday of 31 miles of trails. The previous best was 22 miles of trail riding. It's a great workout without the drudgery. Most people don’t know I’m running an electric setup, because it’s relatively quiet. I would love to give the gruber assist a try to see if that is all the power I need. So any input from those using it in the trails would be helpful.

I recently demoed a high end carbon fiber specialized stump jumper at around 26lbs. with a retail cost of $7K. While riding in the woods, it still felt more like work. I had a lot more fun with my setup. Would be interested in what the minimum power level would be to keep in the fun factor since a light weight setup would make a difference in performance.

 

[VSkudarnov]

Some pics as promised:

The Bike on the evening after-work trip.

Where is the motor?

Waiting for a larger bag (4x4S fitted into the current bag - 10ah)

"The Magic button" and my blackberry custom super-holder

 

[kfong]

That setup is looks great, super light compared to any ES build. Must feel like you are riding a high end CF frame. Can't beleive you got the whole bike for such a price. Have you logged on any big distances. The most I've been able to do on mine with pedalling is 35 miles on the streets and I recently did 33 miles in the trails. I was most proud of the trail miles since it meant I assisted quite a bit, but still felt great after the ride. My usable amp hours is slightly under 20amps. I would actually move that red "magic" button on the outside of the brakes inverted so my front index finger would be able to hit it anytime I needed it :lol:

 

[VSkudarnov]

I do not have the CycleAnalyst (they delayed shipments) to measure how much current does it take.
Gruber says 3-6 amps.
It should give me 3-6 hours of constant 10-15% uphill at 10-15kmh. So best case - 90km uphill and at least the same downhill.

This thing is very efficient - for example, during the 24km evening ride (377m <-> 727m) the cell voltage dropped from 4.10 ->4.00. And that's on half of my total battery (4x4S).

 

[adrian_sm]

Bike looks great.

Waiting for a larger bag (4x4S fitted into the current bag - 10ah)

If you are still looking for a larger bag, I have been really happy with the large Topeak Aero Wedge. I can just fit 4x 5s5000mah LiPos in for my friction drive build. Here is what it looks like stuffed full of LiPo on my bike.

It comes in two models:
Topeak Aero Wedge QuickClip
Topeak Aero Wedge Strap On

- Adrian

 

[Ykick]

That is amazing, thanks for sharing this!

 

[VSkudarnov]

Bike looks great.

Waiting for a larger bag (4x4S fitted into the current bag - 10ah)

If you are still looking for a larger bag, I have been really happy with the large Topeak Aero Wedge. I can just fit 4x 5s5000mah LiPos in for my friction drive build. Here is what it looks like stuffed full of LiPo on my bike.

- Adrian

Thanks Adrian. I have ordered the Topeak MondoPack (http://www.topeak.com/products/Bags/mondopack) - it is larger so 8x4s should fit. Worse case I will fit 6x4S.

 

[adrian_sm]

Oooo. I hadn't seen the Mondos before. Thanks for the heads up.

The MondoXL looks huge. Is that the one you got?

It looks like the pack narrows down quite a bit at the base, this is what will restrict how many LiPo bricks you can jam in.

[EDIT] Pics for reference
MondoXL

AeroWedge Large

 

[VSkudarnov]

Yup, I have ordered MondopackXL on Ebay from a UK supplier for $60 (with postage).

 

[Green Machine]

Man i think that seat post bag is too big of a give away...

That bike deserves a more stealthy solution like maybe a battery backpack...or a topeak bag on a rack....I think that battery bag on the seat post sticks out like a sore thumb.

That bike needs to be stealth.

 

[mrzed]

I'm convinced that for electric bicycles - as opposed to the electric motorbikes with pedals that are common (and fun) on ES, this is one of the best possible solutions. I'd love to see up to 300W continuous being able to run in the seat tube like this. It may not push you to 70kph or have blistering acceleration, but the range could be amazing.

 

[Green Machine]

I am curious...how loud is that seat tube?

 

[Hillhater]

RANGE , POWER ,STEALTH..
pick any two, but i doubt you can have all three combined.

My Ebike will do 100miles on one 10Ahr pack..
.. I have to pedal a LOT, and i only use the elec assist when my lungs are bursting .......but i have range bragging rights !

I dont see much point in making the Gruber too "stealthy" ... it hasnt got the power to attract that much attention.

 

[Green Machine]

Man hillhater....

Dont you see...

That thing was designed to be stealth...to win races....lycra races....not ebike races (which are rare)

100 percent that thing was designed for stealth.

I am convinced it was used in the tour de france...best use of youtube investigational reporting anywhere....no matter what miles says. miles for some reason has faith in fellow riders....he doesnt realize that some will lie cheat and steal to achieve their means. I live in SF... a la barry bonds....i know what its about.

Anyway just a small point...to put a cycle analyst on that thing where people can see straight away its electric should be some sort of crime.

Also having a battery pack with wires hanging out seems like some sort of weird contradiction.

This is the most stealth electric system ever invented....why were the originators so obsessed with stealth if it werent to win races?

Anyway how quiet is that machine? I am curious....i am contemplating entering some lycra races in street clothes.....just to have stories to tell my friends later....i want to enter some cycle races dressed as a hippy.

 

[Hillhater]

EGM,..
yes i am aware of the history/alleged use of the Gruber, but this particular bike is not being used in any road races so the stealth factor is not a requirement.
The stealth design features of the drive actually leave it with some major drawbacks too ( battery size/location, being the least issue)

 

[Green Machine]

I am just saying if i had one of those things i would put it to its intended use and win some lycra races...it's a waste not to.

Imagine the document...the testimony...the laughs later.

Dont they have mountain bike races he could enter...endurance climbs or something?

Do MTB endurance guys wear lyca? (i.e. are fun to film)

 

[VSkudarnov]

Ok, couple of things to clarify:
- CA: I have ordered one with a large screen. I am not into races, thus I just need a tool. if you want to be stealth - order a Speedict box (it will send Current/Speed/Ah by bluetooth to your phone). My goal is to go with a steady pace into 10-15% uphill (which can last 5-10kms here) watching the scenery around.
FYI Tomorrow I will try to do:

this one - until noon (approx. 1000m climb): http://www.gpsies.com/map.do?fileId=flllrwsizqtbnfmw
if I have battery/leg power, and will also do this one (another 500m up and then 1300m down): http://www.gpsies.com/map.do;jsessionid=170F09F37AFF54549520EE4152FF2E4B?fileId=apgnncgsspmfzwid




- battery bag: ignore the current picture, it is temp. The larger bag will come next week. And no, it is not too large, it is used on the multi-days MTB marathons to host 2 tubes/tools/energy bars etc. The bike is in the size L, so it would perfectly fit (wires go from the seatpost directly into the bag. Will update.
- Lycra: I wear lycra shorts too it is very convenient for long day trips.

 

[Green Machine]

Thanks for the tip on the speedict box...looking into it.

Here is an interesting data point...

That system is a very specialty system...not really sold in the open. Lets just say there is not a buy it now link on the company website or even a price.

I think it is marketed towards cheaters..thats just my guess.

Anyway the system for stem motor, controller and battery reportedly costs $3100 US new.

Thats an interesting price point....

Does anyone know if the stock battery is designed to fit in the tubes of the frame?

Hats off to Vskud for finding such a steal on the used system with bike...i wonder what the story of the original owner was...if he actually paid full pop for that system for pleasure.

I find this entire system fascinating....and would love to see some test videos etc.

 

[VSkudarnov]

There is no BIN pricing on the company's website because they do not sell directly, only through the network of dealers, who take care of the installation, maintenance (lubing the gears) and warranty.
However, you can find the prices among the prospects (Download section).

It is not marketed towards cheater, but to rehabilitation, old and just lazy mountain bikers If you are in Austria, they offer a trial weekends. Every dealer has the demo bike as well.

The original owner bought it to go to work, but never used (both original batteries died from not being charged, original knobby tires not worn at all). He put on the local auction site (Ricardo) with a brief description and no picture (stupid). Therefore, there was just one bidder - me.

 

[panurge]

Hi

Only for a short report....
As I'm an european bike builder I'm always at Eurobikes exhibition and gruber was there with his stealthy system if I well remember at least from 2006..... The larger exhibition in europe is not the best place to hide from the press eyes his hidden system....the gruber was well known to insiders, years before the Paris-Rubaix race doped-bike scandal come out....

I can report that when I tryed this system, (in a CF 8kg bike) I was surprised how a 100-200w motor can do for you in a superlight road bike, but at the same time how it was noisy related to his small size and power....later, when I heard about Cancellara, I was not surprised, only I could not figure how the others racers could not heard this noise....maybe due to not-paved road and people voices......or maybe Gruber has made some customs works for Cancellara....
This is an old 2007 video http://www.youtube.com/watch?v=hbjhao_IKZg, you can heard on it the noise....the improvements made by gruber in these years was all intended to reduce this noise and add some power....
Anyway the system is really cool for trained road bikers and is ingenious as simple...

Jules

 

[VSkudarnov]

I concur, it is noisy. The latest (v3.15 from 2011) is promised to be half-noisy.
But the voice helps. And by the frequency you know whether you are in the optimal gear, or not.

Brief after testing in the real mountains: it is something. The steeper the uphill - more you feel the help. I could not believe I can go such steep uphills without losing my breath!
Efficiency: after I logged a 1000m elevated track, I only used 1/2 of 10ah battery (cell voltage dropped from 4.1 to 3.85V). After continuous use (maybe 30-40min), the seat tube is just little warmer.

PS The cows are really curious about the noise ))

PPS. The funny thing is that I cannot finish my half-battery. I think I do not need all eight 4S lipos, four is enough for a day trip.