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

[Chalo]

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?

When I have used needle roller clutches (and needle roller bearings) on aluminum or unhardened steel shafts, I have bought hardened precision sleeves and affixed them to the softer shafts. That not only provides a suitable surface for the rollers, but also a larger radius through which to transmit torque. In the relatively low torque applications I was building for, I bonded the sleeves on. In this case, using a heavy press fit or a key would be a good idea.

 

[rp3]

I attempted this mod from Denisesewa on the weekend. I didn't have a staple so I tried some tie wire I had, lol 41amps, 2kw's and a skipping belt brought an end to that! :lol: I ended up just leaving the left over solder on there for an increase from 1010W up 1350W. A quick 25km ride with the same tight belt I normally run was uneventful, the extra power was nice especially as the battery dropped in voltage.

..

 

[rp3]

I spoke too soon. My crank free wheel has died, and just after I'd ordered all the parts for a primary chain conversion. I think I'll try a hub motor this time around...

 

[Chalo]

You can always use a normal non-freewheel crank, as long as you run the motor at a suitable speed and reduction for pedaling along. It's inexpensive and reliable.

 

[rp3]

Yeah, I'm going to give that a try. No ebike over the long weekend would kill me! :lol:
Just hope I don't slip the throttle on accidently. :wink:

 

[skyungjae]

were you using the freewheel that came with the kit?

 

[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.

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

Hey Mike,

Checked the sheets against the frame - looks like a good fit.

Can't find the 13mm socket to remove the 12t freewheel.. will have to install the plates another day.

The hose clamp bracket is also different on my kit.

 

[LightningRods]

Can't find the 13mm socket to remove the 12t freewheel.. will have to install the plates another day.

If I remember right that small sprocket freewheel wants a 12mm socket. Annoyingly, a normal thick wall 12mm socket won't fit down into the freewheel. I tried three different hardware stores trying to find a special thin wall socket. I finally gave up and went to Harbor Freight, a company that sells cheap Chinese tools. I figured I'd buy a cheap socket and grind it down to fit. Turns out it was so cheap that the walls were already paper thin and it fit perfectly. You'll want vice grips or channel locks to grab the inner part of the freewheel so you can get the nut loose. Several forum members have taken these freewheels to bicycle shops that couldn't figure out how to get them off. Be patient. It's not that hard.

 

[rp3]

were you using the freewheel that came with the kit?

Yeah, stock. The secondary reduction freewheel is now making some nice clicky/crunchy noises.

 

[full-throttle]

The original nut was lost, so I changed it to a nylock. Pretty sure it was 13mm and whatever I had fitted. Just cannot find it.

 

[bee]

Destroyed another chain and bent the front chainring again today. Anyone else having this much trouble with 2000w+ on a 9+ speed bike without using a chain guide in the front? Mine should come in a few days but I've been anxious to play with the bike. I can use the middle 3 gears no problem but the outer ones cause the chain to fall off under hard riding.

It seems to be the protruding screws on the front chain ring assembly that cause the most damage when you drop a chain since they grab the chain and pull it. The stock crank assembly on this bike was pretty smooth so if you drop the chain, the crank rubs against it instead of ripping it apart. Maybe a little 3d printed spacer/cover would be a good fix here.

Luckily this time I used a $10 chain so it broke easily without destroying the derailleur again. I think I'm gonna stick to using cheap chains with this kit, and maybe carrying a spare chain and breaker in my backpack.

Got about 50km on the bike but riding through the mud has destroyed the bearings on my jackshaft already. Time to order the new version?

 

[LightningRods]

Got about 50km on the bike but riding through the mud has destroyed the bearings on my jackshaft already. Time to order the new version?

See if you can order just the jackshaft. I've used hillyterrain's new sealed jackshaft to design new adjustable primary sheets. They're even stronger than my first design and offer another 1/2" of length adjustment for larger pulleys. Everything else on the new kit is the same except for a plastic mud guard that you could easily make yourself.

 

[justforfun]

Jackshaft bearings are 32mm o/d 12 mm I/d easy enough to get!
I tried running without chain guard and had too many problems I think chain guard is a must on this kit!

 

[bee]

Jackshaft bearings are 32mm o/d 12 mm I/d easy enough to get!
I tried running without chain guard and had too many problems I think chain guard is a must on this kit!

Ah, great. 6201 bearings according to the wiki: http://endless-sphere.com/w/index.php/EBike_Motors_Middrive_GNG_Gen1

Anyone know if the stock bearings are 1RS or 2RS? I like to use my skateboard in the rain and noticed a big increase in longevity when I switched to 2RS.

LightningRods, can I get your 3d models for the Gen1 upper adjustable kit? It would make it much easier for me to design some snap-on plastic covers.

 

[LightningRods]

LightningRods, can I get your 3d models for the Gen1 upper adjustable kit? It would make it much easier for me to design some snap-on plastic covers.

There is no 3D model for the sheets. It's a 2D cutting path. I'll provide you with the profile if that will help. What are you covering, the jackshaft and bearings?

 

[christerljung]

It would also be nice with a 3d-printable chaincover at the first reduction (for those who converted to chain). Tried a little in openSCAD but it's too tricky at my level right now. Rounded edges... How would that code look :?

 

[bee]

LightningRods, do you have the file used to generate this render?

I wanted to make something that would cover the jackshaft, freewheel, bearings, and possible the large gear.

christerljung, for funky shapes I recommend using inkscape/illustrator to draw them and then assemble in openscad using the extrude feature: http://repraprip.blogspot.ca/2011/05/inkscape-to-openscad-dxf-tutorial.html

 

[spinningmagnets]

bee, I applaud efforts to create the file that will allow 3D plastic printing of a cover, however, if you are in a hurry, I can imagine making a cover by drilling mount holes around the rim of the bracket, stretch a thin cloth over the area of the new cover, insert small bolts through the cloth and into the mount holes with tape around the threads to protect them, brush on some type of epoxy or hardening agent...just enough to make a firm shell.

Remove the thin shell, and reinforce the outside of it with fiberglass from a small boat hole-patching kit. Just a thought...

You could also use several small L-brackets on the inner edge of the existing bracket, and that would allow you to attach a curved section of sheet-metal as the cover.

 

[speedmd]

One could easily 3d print a handy form of a extremely sexy cover if one were good with surfaces. 8)

I would do it if I knew how to blend surfaces a bit better.

 

[christerljung]

christerljung, for funky shapes I recommend using inkscape/illustrator to draw them and then assemble in openscad using the extrude feature: http://repraprip.blogspot.ca/2011/05/inkscape-to-openscad-dxf-tutorial.html

Thanks, i will try the inkscape way.
Does anyone know where to buy the magure throttle for a nice deal, with shipping to Sweden?

On ebay there is an alternative but they are from Australia and looks a little different?
http://www.ebay.com/itm/MAGURA-ELECTRIC-THROTTLE-ASSEMBLY-317-6-MODEL-/160891877412?pt=AU_Motorcycle_Parts_Accessories&hash=item2575e73824&vxp=mtr

I found this one, but is it the same model?
https://www.evdrives.com/ProductDetails.asp?ProductCode=THR-Magura-ASSY&CartID=1

 

[Tinto]

After shopping around for a bit I bought a magura throttle from evdrives as it came with the matching left hand grip.

 

[MotoMel]

Aagh!

This is MotoMel from BikeMotive. I didn't hear until someone mentioned it to me through email that the spiralocks are unwinding. For whatever reasons, our builds didn't happen to have that problem. IN ANY CASE, I am MORE THAN PLEASED to send out as replacements the Omega-style retaining rings that solve that problem! Do you still need one?

And for anyone who is going after the Omega retaining ring on its own, the ring is a heavy-duty model sized 1-1/8" rather than 30mm. The 1-1/8" sits in a deeper groove, whereas the 30mm does not work well with the fact that the threading reduces the effective rod size.

MotoMel

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

 

[bee]

christerljung, for funky shapes I recommend using inkscape/illustrator to draw them and then assemble in openscad using the extrude feature: http://repraprip.blogspot.ca/2011/05/inkscape-to-openscad-dxf-tutorial.html

Thanks, i will try the inkscape way.
Does anyone know where to buy the magure throttle for a nice deal, with shipping to Sweden?

On ebay there is an alternative but they are from Australia and looks a little different?
http://www.ebay.com/itm/MAGURA-ELECTRIC-THROTTLE-ASSEMBLY-317-6-MODEL-/160891877412?pt=AU_Motorcycle_Parts_Accessories&hash=item2575e73824&vxp=mtr

I found this one, but is it the same model?
https://www.evdrives.com/ProductDetails.asp?ProductCode=THR-Magura-ASSY&CartID=1

It looks like the inkscape plugins are more mature:
http://www.thingiverse.com/thing:25036

I prefer Illustrator myself so I ported the old illustrator plugin to CS6 for this project:
http://www.thingiverse.com/thing:69563

 

[DaveP]

In the process of fitting the adjustable sheets I removed the freewheel on the jackshaft. Even though new it did not run very smoothly so in view of the problems encountered by skyunjiae and others I decided to risk taking it apart and loosing the ball bearings. Interestingly the races are not particularly smooth and lubrication is a minimal film of oil. This will give no protection from the ingress of water causing corrosion, or because of the lack of lubricant increased wear will be probable.

I lightly polished the grooves holding the ball bearings and reassembled the freewheel making sure everything was well packed with lithium grease.

The freewheel now runs much more smoothly and does not feel "lumpy" when turned, so hopefully it will now be reliable. If not then I guess I will replace it but if you have a new kit it's worth a try.

DaveP

 

[skyungjae]

Aagh!

This is MotoMel from BikeMotive. I didn't hear until someone mentioned it to me through email that the spiralocks are unwinding. For whatever reasons, our builds didn't happen to have that problem. IN ANY CASE, I am MORE THAN PLEASED to send out as replacements the Omega-style retaining rings that solve that problem! Do you still need one?

And for anyone who is going after the Omega retaining ring on its own, the ring is a heavy-duty model sized 1-1/8" rather than 30mm. The 1-1/8" sits in a deeper groove, whereas the 30mm does not work well with the fact that the threading reduces the effective rod size.

MotoMel

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

Thanks Mel, but the Fastenal 30mm snap ring has been holding up to everything I can throw at it.