GNG, 1000W 48V BB-drive, $400

[Miles]

since herringbone gears are apparently patented................

What?????

As they've been used since the 19th century..................

Unfortunately it's totally ok to file invalid patents, and companies will do it in the hope that it'll scare an engineer from giving a second thought to their idea. A quick google search shows that there are dozens of patents for various herringbone gear implementations.

The best way to erode the validity of these patents and open up the knowledge for the greater good is to release and use open source derivatives

I'm sure there are patents related to specific aspects of double-helical gears. That's not what you wrote, though

 

[joec]

Well, here it goes! I just placed and order for two raw motors from Mister Tao. I'll report back when something happens.

An update- my order status on Mister Tao says "refund". The money is apparently in some kind of holding, not back at my credit card, and I can't find a different link or seller on there to try another purchase. I'm going to try to figure out how to get my money back unless somebody has another idea.

 

[justlooking]

you are not the first to get a refund from them instead of the goods ,, and the last one was held ,,

i dont know if they got the money back into their account or if you have to spend it on their site,

 

[bzhwindtalker]

I was trying to switch back to the original controller today (from a KU123) and I discovered I have a dead hall and I had been runing sensorless for a while. Anubody knows where to get replacement halls for this motor? The hall board is labeled 120° btw.

 

[LightningRods]

Well, here it goes! I just placed and order for two raw motors from Mister Tao. I'll report back when something happens.

An update- my order status on Mister Tao says "refund". The money is apparently in some kind of holding, not back at my credit card, and I can't find a different link or seller on there to try another purchase. I'm going to try to figure out how to get my money back unless somebody has another idea.

When I ordered my GNG kit from Mr Tao I got 'refunded' as well. I wrote them and was told the kit was temporarily out of stock. I waited about a week, placed my order again and it went through. You also have to message them for an actual cash refund. No "refund" button. I hope you can get the motors!

EDIT: I just sent them a message saying that I want 10 of those motors to be followed with an order for 100 if the product is satisfactory. I'll let everyone know what they have to say to that.

Hillyterrain's GNG v 1.1 arrived at my shop. I will take photos and measurements on Monday.

 

[LightningRods]

As promised here are some photos of GNG Gen 1.1:

The jackshaft tube now holds the sheets together and maintains the spacing. The one 5M bolt and spacer tube is just to provide a mounting point for the hose clamp bracket.

The threaded tabs on the front are for the plastic mud guard.

The new jackshaft tube is no bottom bracket I'm familiar with. The internal shaft and bearings appear identical to v. 1.0. The freewheel and pulley are the same.

A comparison of the inside and outside of the new and old primary side sheets. The diameter of the center hole is smaller in the new sheets.

I can't really adapt the existing upper adjustable sheets to this jackshaft. It looks like I will be developing a new upper sheet set.

 

[skyungjae]

Hmmm... is GNG phasing out their original version altogether?

 

[LightningRods]

Hmmm... is GNG phasing out their original version altogether?

As far as the original open jackshaft with bearing blocks goes, I'd say yes. This is too close to the same thing to be another model like Gen 2 is. Other than the jackshaft tube and sheets, and the added mud guard, everything else seems to be identical. Even the terrible belt tensioner and rotary razor blade drive pulley.

 

[LightningRods]

 

[bee]

So has anyone pointed out some of the progress we have made in this thread to the GNG devs?

 

[Mechdude]

Hi all, been a while since I'v posted. My bike was off the road for 3 wks while I waited for a new belt, than reassembled with Lightening Rods adjustable sheeve plates.
Found the process of tru-ing everythng up difficult, but the end result seems to be quite robust, quite and running nicely....
However it seems that my primary free wheel is now about to collapse.
Under high torque situations (launching), I get a loud clacking noise and lack of drive until the speed builds up and torque reduces. Sort of like an unwanted torque limiting device. :-(

Could someone summarise, or point me to a solution for this problem, thanks.

 

[spinningmagnets]

GNG mods thread
http://endless-sphere.com/forums/viewtopic.php?f=28&t=46891#p695839

skyungjae found an 11mm shaft adapter that seems to work well (so far) with the original 1.0 version of the GNG brushless 450W jackshaft. This adapter allows a common and strong 13T BMX freewheel to be used. The original 12T is known to be weak and short-lived, but it allows a better reduction compared to the 13T. For customers who are afraid to ask, I think GNG may be putting the bosses kids through college from the profits selling replacement 12T FWs.

I am convinced the original chainrings (44T on the primary) were chosen to allow the kit to be mounted on a wide variety of frames without the chainring hitting the chainstays. If you don't jump curbs or crawl over large rocks/logs (off-road) one eoption is to attach a larger diameter chainring. I have heard of 52T being used to help the reduction (stock motor RPMs are too high to add pedaling at top-speed when using 48V). A 60T is available for $40-ish, but I recommend making a cardboard mock-up of a 60T to check fit before spending money on that.

 

[speedmd]

I have the front end almost done on my kit. Primary will be #25 chain and a 12/72 reduction. The 12 tooth freewheel is the next sprocket line to work out. Looking for some sort of friction clutch that I could use to mount freewheel to. I know the stock unit will no last long.

Planning to use the stock gng Crank arms, with acs flanged freewheel and three rings 39/ 53/ 53. Stock 9 speed rear. Will see if it all fits soon.

Still no stock on the 6s 8000mah zippy batteries. Need to rethink this...soon.

 

[skyungjae]

So far, it is working fine. Just keep in mind that not all the 13T BMX style 30x1.0mm freewheels are built equally. My ACS Crossfire is holding up fine, much better than all the loose bearing crank freewheels. Unfortunately, it does share the same weaknesses against sand and dust.

If you do plan on going the BikeMotive adapter route, I'd suggest picking up some 30mm snap rings just in case the retaining ring on yours plans on unwinding itself. :lol:

GNG also has a freewheel adapter (in the pull down menu for the 13T motor sprocket), but I have no idea what it looks like or if it's for 30x1.0mm freewheels. You may want to shoot them an email if you plan on ordering a replacement 12T.

http://www.gngebike.com/parts

 

[christerljung]

However it seems that my primary free wheel is now about to collapse.
Under high torque situations (launching), I get a loud clacking noise and lack of drive until the speed builds up and torque reduces. Sort of like an unwanted torque limiting device. :-(
Could someone summarise, or point me to a solution for this problem, thanks.

I had a similar behavior on my GNG-commuter. It was simply the freewheel unscrewing itselft against my homemade protectionshield. Just had to put it together again with some new balls, all of them got lost when things fell apart. I had that clicking noise for about a month before i realized what the problem was. Also ordered the acs like skyjungae. But i like the original GNG so i havent used it yet.

 

[LightningRods]

The Mr. Tao connection for motors looks like a fail.

LightningRods:2013-03-26 10:51:53
Can you please tell me if item-18586248326 is available? It is advertised on your site so I assume it exists.
Thank You-
Michael
Sky:2013-03-26 16:30:40
LightningRods,
thanks for your message, we are sorry to tell you that, we can't send it for you, sorry,sky

 

[DaveP]

Planning to use the stock gng Crank arms, with acs flanged freewheel and three rings 39/ 53/ 53. Stock 9 speed rear. Will see if it all fits soon.

I have recently obtained a gng kit and a set of adjustable sheets from LightningRods. I will start to fit it to the bike after Easter when I have some time and use the bike through the summer. In the autumn I wish to change both the primary and secondary drive to give me a lower cadence, aiming for 70 to 80. I plan to use a 48v 15ah or 20ah battery depending on weight and overall balance.
So my question based on a lack of understanding is why so many gears when there is such a range of power output from the motor? I understand that a close ratio gear set makes climbing hills ,for example, easier on a normal bike but is this such an advantage with this kit?

Thanks

DaveP

 

[skyungjae]

I was able to get photos of the freewheel adapter from Jon from GNG.

Here's what they look like:

Freewheel Adapter

It looks like the freewheel adapter is a no-go in terms of replacing the 12T jackshaft freewheel. It looks like it has an inner diameter of approximately 18mm... way bigger than our 11mm keyed shafts. Unless I'm missing something here...

However, the 13T sprocket looks like it would work. You'd just be pedaling against the motor... maybe set up a 0.01% regen? :lol:

I have no idea why he's using the inches side to measure the ID of the sprocket. This guy has got to have a clear ruler and/or dial caliper. :?

 

[LightningRods]

However, the 13T sprocket looks like it would work. You'd just be pedaling against the motor... maybe set up a 0.01% regen?

Or put the freewheel in the large drive pulley/sprocket on the primary side where there's room for it. Isn't it true that if the freewheel is on the primary side it's also subjected to lower torque forces? I think that unless you pedal 90% of the time with no motor assist that it's worth the tiny amount of drag from the jackshaft.

 

[Chalo]

However, the 13T sprocket looks like it would work. You'd just be pedaling against the motor... maybe set up a 0.01% regen?

Or put the freewheel in the large drive pulley/sprocket on the primary side where there's room for it. Isn't it true that if the freewheel is on the primary side it's also subjected to lower torque forces? I think that unless you pedal 90% of the time with no motor assist that it's worth the tiny amount of drag from the jackshaft.

If the freewheel were on the primary stage, you might even be able to use a Torrington needle roller clutch instead of a toothed ratchet. Some of those are equipped with a row of roller bearings on either side of the clutch, in the same housing. They don't have any axial retention, so there would need to be some kind of thrust washer used in combination.

http://ecx.images-amazon.com/images/I/51QS1fH8RrL._SL500_AA300_.jpg

This type of one-way roller clutch was used on USPD and Currie kits in days of yore. Theirs was a little undersized for the job, in my opinion.

 

[spinningmagnets]

That's a great suggestion, Chalo. The only thing I would add (due to my experience using those in a friction-drive) is that they must ride on a case-hardened shaft. My experience was in using these roller-clutch bearings at 1,000W using a 1/2-inch shaft. If they were "almost" strong enough...we could add a case-hardened shaft spacer to the stock GNG shaft and then use a larger roller-clutch bearing?

 

[speedmd]

Thinking possibly a Friction / safety clutch to mount freewheel to keeping drive line safe.

The new large primary sprocket hub I turned up for the new sprocket I left material to add freewheel threads to it if I decide to try that at some point. Thinking also like many have mentioned to go direct to the rear wheel from the primary side jack shaft may be a good way to go on higher power builds.

 

[heathyoung]

If that 13T solid gear is any good, its a pretty trivial upgrade when you swap to a chain drive for the primary reduction (most of those 25H sprockets have flanged freewheels that fit them).

 

[full-throttle]

Received the adjustable plates from LightningRods, both primary and secondary. Thanks!
The building number on parcel was covered by ParAvion sticker and it still managed to find me

Will fit it on the bike this weekend.

 

[LightningRods]

Received the adjustable plates from LightningRods, both primary and secondary. Thanks!
The building number on parcel was covered by ParAvion sticker and it still managed to find me

Will fit it on the bike this weekend.

Thanks F-T! PM me if you have any questions.