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

[spinningmagnets]

Yes, a wider belt will help the holding power and reduce skipping. LightningRods kit will allow the options of a chain primary or a 20mm wide belt. Because the motor has the ability to use the bikes gears to downshift, it actually still performs well at 36V which would make the battery pack lighter and more affordable. Of course most buyers are focusing on the type of performance you get at around 48V, and a few want 72V, so whether to use a chain or belt is up to each users profile.

For 72V I would recommend just planning on a chain primary, and fabricating a housing to keep mud off the drive and also save your pants from being torn...might have the additional benefit of making the high-RPM chain primary a little quieter. At the lower power levels, the quietness and no-oil belt is an option for those who want those features.

 

[comradegerry]

After reading back through the thread it looks like I will wait for the Lightening Rods solution of 18 tooth slip on cog with a 120 tooth pulley in 20mm format, with the adjustable sheets upgrade to arrive. Seems like that will work for me as I am not looking for crazy power, more interested in reliable at 48v.
It is one hell of a thread with a lot of great info.

 

[t0me]

doh!

 

[gknowes]

A long, long, wait on that 18t drive pulley.But this drive will be built to last a long time, so i seat an i wait ,an i wait. 8)

 

[MAGICPIE3FOCUSPOWER]

Woowww great topic with great info!

But after reading some replies...I should avoid this kit?
Because I need a reliable kit for every day use....

So Cyclone is a better choice?

 

[kifukarider]

After reading back through the thread it looks like I will wait for the Lightening Rods solution of 18 tooth slip on cog with a 120 tooth pulley in 20mm format, with the adjustable sheets upgrade to arrive. Seems like that will work for me as I am not looking for crazy power, more interested in reliable at 48v.
It is one hell of a thread with a lot of great info.

At what amperage do you plan to use with 48v? I think the stock 48v system is reliable. I too look forward to seeing LightningRod's next accomplishment, but in not in the context of reliability.

 

[deepfraught]

That is a good question, I dismissed cyclone initially but now with a couple wider BB bikes with IGH I could deal with an agricultural downtube clamp, the Felt MP doesn't even have drink bottle mount so I could even gain one by a cyclone bracket pickup.

P.s. would like to see what recumpence is up to with comparable option, have been following but he seems busy in demand.

 

[kifukarider]

Woowww great topic with great info!

But after reading some replies...I should avoid this kit?
Because I need a reliable kit for every day use....

So Cyclone is a better choice?

Why would you avoid it? The stock GNG is a reliable kit for everyday use. I haven't had any failures. If you want to go up to 30 mph without pedaling, the GNG kit will do the job without complaint. The weakest link appears to be the belt. Carry a hex key and spare belt should the need arise. It's easier to change the belt than fixing a flat.

 

[MAGICPIE3FOCUSPOWER]

Thank you!

I like this kit better it looks better design then Cyclone 2400W kit.
Also the price is much better!

Yes No problem for carrying a spare belt
I like the belt idea, looks better then chain method?

 

[kifukarider]

In light of all the concerns about reliability, I have to post this:

An ebike can never break--it can only become a bike. You would never see an "Ebike Temporarily Out Of Order" sign, just "Ebike Temporarily Bike. Sorry for the convenience. We apologize for the fact that you can still get there."

I've only had my ebike become a bike once so far and that was because I wanted to see what the battery low voltage cutoff was.

 

[comradegerry]

At what amperage do you plan to use with 48v? I think the stock 48v system is reliable. I too look forward to seeing LightningRod's next accomplishment, but in not in the context of reliability.

20 amps is all I plan on using at 48v.

I just do not want to be changing belts more than truly needed and think the upgrade is worth the effort.

 

[kifukarider]

At what amperage do you plan to use with 48v? I think the stock 48v system is reliable. I too look forward to seeing LightningRod's next accomplishment, but in not in the context of reliability.

20 amps is all I plan on using at 48v.

I just do not want to be changing belts more than truly needed and think the upgrade is worth the effort.

How many belts have you replaced so far and in how many miles/kilometers?

 

[skyungjae]

At what amperage do you plan to use with 48v? I think the stock 48v system is reliable. I too look forward to seeing LightningRod's next accomplishment, but in not in the context of reliability.

20 amps is all I plan on using at 48v.

I just do not want to be changing belts more than truly needed and think the upgrade is worth the effort.

How many belts have you replaced so far and in how many miles/kilometers?

I hit 499 miles today, and I'm on my original belt.

I didn't note how many miles I had on my GNG when I did the staple shunt mod in mid-May, but it does peak at 35A now. I set my CA to limit the amps at 30A.

I'd say the last 75~100 miles have been with my added power. Bear in mind my riding methods probably differ from the average e-biker. I'm almost always pedaling and always ease onto the throttle. I maintain about 500W when I'm cruising on flattish ground at about 20-25mph while lightly pedaling (my bike is heavy as am I). I'll spike it up to 1500W when I'm riding on the trails for those steep inclines (not from a dead stop of course). :wink:

There is a tad bit of belt wear on one section of the belt, but most of the wear on my belt is due to letting other people ride it. Almost everyone who has ridden it, besides me, has done an accidental wheelie. After one of those wheelies (a much larger one), I did look at the belt and saw wear on about an inch of section on the belt. This past weekend, my SRAM PC971 chain snapped while my friend was riding it on my usual 11 mile trail ride. I was surprised to see my chain go before my belt. I'm trying the SRAM PC951 hoping it's more robust as the cheaper bike stuff tends to be heavier and beefier... not as pretty though.

I believe throttle control is the key to keep the belt alive regardless of stock or added power.

I have two spare belts, and even if I snapped my belt today I could easily get another 1000 miles out of my next two belts. Considering that my belt has outlasted my chain, newly installed when I installed the kit, I view it as one of the many wear and tear parts that should be periodically replaced before failure. I'm probably going to ride it until it snaps though. :lol:

I was pretty enthusiastic about the availability of a wider belt option from LightningRods, but the likeliness that I'll actually do it is decreasing as I continue to ride the GNG the way it is. At this point, my tinkering nature is probably what'll get me to pull the trigger on any further upgrades. :lol:

On a side note, I do think the bottom bracket, cranks, and chainring set is too weak for any bumpy off road riding/jumping. When people ask me what to buy regarding GNG for trail duty, I suggest that they contact Jon at GNG directly and price the kit without the bottom bracket, cranks, and chainring (Jon doesn't like to do this, and I can't guarantee he will do this); contact Paco at Cyclone and order one of those 148mm ISIS bottom brackets with their ISIS freewheeling cranks and chainrings excluding the Dicta freewheel (which craps out in dust very quickly); and order a White Industries flanged freewheel from Sick Bike Parts.

I'm sure the majority of GNG users, who ride on the street and smooth unpaved paths, do not have any issues with the GNG crankset.

 

[kifukarider]

How many belts have you replaced so far and in how many miles/kilometers?

I hit 499 miles today, and I'm on my original belt.
...
On a side note, I do think the bottom bracket, cranks, and chainring set is too weak for any bumpy off road riding/jumping.
...

I appreciate you posting your real world experience skyungjae. It sounds like you've got some hard miles on your bike too. Did you replace your bottom bracket/cranks/chainring after a failure, or was it preemptive?

 

[spinningmagnets]

kikufarider, most of the builders around here are interested to see how much power can be put through a kit without breaking something. This kit is reported to be pretty good in stock form for a commuter bike.

The stock kit without any mods at all works quite well at 36V, and the only change truly needed is the stock motor-pulley teeth must be hand-sanded to remove the sharp edges. If you do NOT take the bike on jumps, and use a full-suspension frame, the stock BB-set (pedal axle) is adequate.

The stock Dicta freewheel is just adequate. But when it wears out, a higher-quality ACS-Crossfire freewheel is under $20 to upgrade it then.

 

[skyungjae]

I appreciate you posting your real world experience skyungjae. It sounds like you've got some hard miles on your bike too. Did you replace your bottom bracket/cranks/chainring after a failure, or was it preemptive?

I made most of my changes after something broke. My current set up is not as reliable as my "bomb proof" set up, but it has made it possible to cruise at higher speeds. Since I spend plenty of time on asphalt, it seems worth while to keep it the way it is. It's also fun showing off pedaling at 30+mph looking like an incredible athlete on a huge downhill bike. :lol:

Crankset Review:

1. GNG set up failed on day 1. Threads on the freewheel crank arm stripped. I splined it and pinned it to the freewheel, but it failed after a few hard rides.

2. GNG chain ring + BikeMotive crank arms & ACS 16T freewheel. BikeMotive cranks were ISO taper not JIS. I ran it with the freewheel on the outside of the GNG chain ring temporarily until I could put together my own chain ring set up.

3. Dicta freewheel, SickBikeParts steel 48T chainring bolted to my Blackspire 34T aluminum chain ring w/ random bolts from ace hardware. Bent the BB spindle during this set up. It seemed okay except that my bike would spit the chain off the front ring when my suspension compressed deeply and rapidly. e*thirteen chain guide fixed that. Then the Dicta freewheel crapped out pretty fast from all the dust and sand from my trail riding.

4. Cyclone 140mm ISIS BB & freewheeling cranks + my SickBike Blackspire chainrings + White Ind. ENO = my bomb proof set up.

5. Current set up: Cyclone inner 32T/44T chain rings, swapped the outer aluminum 48T chain ring w/ the steel SickBikeParts one.

http://endless-sphere.com/forums/viewtopic.php?f=3&t=46164&start=75#p730620

 

[skyungjae]

kikufarider, most of the builders around here are interested to see how much power can be put through a kit without breaking something. This kit is reported to be pretty good in stock form for a commuter bike.

The stock kit without any mods at all works quite well at 36V, and the only change truly needed is the stock motor-pulley teeth must be hand-sanded to remove the sharp edges. If you do NOT take the bike on jumps, and use a full-suspension frame, the stock BB-set (pedal axle) is adequate.

The stock Dicta freewheel is just adequate. But when it wears out, a higher-quality ACS-Crossfire freewheel is under $20 to upgrade it then.

I have yet to remove the sharp edges on my motor pulley. It's one of those things I do have planned though when my belt goes.

I think part of the reason why I bent my BB spindle so easily is due to using the ISO taper cranks. It had to have put more force toward the ends of the spindle regardless of my plush 7" of travel. :lol:

The ACS Crossfire is definitely an awesome freewheel and a huge upgrade over the Dicta. It's definitely more affordable than the White Industries ENO. The Dicta is actually not that bad so long as you keep it clean.

Personally, I just liked the sealed bearings of the White Industries ENO.

I try to live by the "buy once, cry once" philosophy when it comes to any purchases. I've clearly failed on my personal GNG journey. :lol:

I just hope I've been able to positively contribute to the GNG Gen 1/1.1 community.

The resources are clearly out there to make this kit "bomb proof." It just takes a little work at the moment.

I'm not sure if LightningRods still intends on creating a full kit with both the power and BB "perceived" shortcomings addressed. At least we know that there are fixes available that seem to address all types of use. :wink:

 

[MAGICPIE3FOCUSPOWER]

Where can I find some info about the LightningRods kit?

Thank you!

 

[skyungjae]

Where can I find some info about the LightningRods kit?

Thank you!

He hasn't made one yet, and there is the possibility that he may not make one. It was just one of those things that he had showed some interest in putting together. To him, and many agree, it's kind of a waste buying a kit that you end up replacing almost everything short of the motor.

He's got a lot on his plate right now regarding belt/chain drive upgrades. That's probably why he's not posting as often as before.

 

[kifukarider]

kikufarider, most of the builders around here are interested to see how much power can be put through a kit without breaking something. This kit is reported to be pretty good in stock form for a commuter bike.

I am also a builder interested in performance upgrades, emphasis on performance not upgrades.

The stock kit without any mods at all works quite well at 36V, and the only change truly needed is the stock motor-pulley teeth must be hand-sanded to remove the sharp edges. If you do NOT take the bike on jumps, and use a full-suspension frame, the stock BB-set (pedal axle) is adequate.

I think you understate the stock kit. Without any mods at all, it works quite well at 48V. Hand-rounding the primary motor-pulley teeth will be the realm of only the most near-sighted performance scratchers. There is much lower hanging fruit.

The stock Dicta freewheel is just adequate. But when it wears out, a higher-quality ACS-Crossfire freewheel is under $20 to upgrade it then.

I think "But when it wears out" might better be phrased "But if it wears out". Your freewheel recommendation is however valued information.

 

[MAGICPIE3FOCUSPOWER]

Where can I find some info about the LightningRods kit?

Thank you!

He hasn't made one yet, and there is the possibility that he may not make one. It was just one of those things that he had showed some interest in putting together. To him, and many agree, it's kind of a waste buying a kit that you end up replacing almost everything short of the motor.

He's got a lot on his plate right now regarding belt/chain drive upgrades. That's probably why he's not posting as often as before.

Ai I didn't know that
Hmm I am preferring using all hardware

Does anyone knows what type/partnumber of belt I should buy?

 

[fabiograssi]

In this page:

http://bikemotive.myshopify.com/collections/ebike/products/freewheeling-crankset-for-ebike-bikemotive

What is the best combo for the gng kit? And which model of central movement should I use with it?

BR,

- Fabio

 

[comradegerry]

Hi Kifukarider

I have done zero miles with the stock GNG setup, strange as it may sound, I want to improve it before I have even used it!

I have a different motor setup at the moment and want to fine tune that one first, then do a back to back comparison.

The GNG is back in a spares box but ready to install if I break the current Astro 3210 setup.

I had already started down one road when the GNG kit came out so now it is a plan B of sorts, it will see active duty at some point though.

I hope this makes sense.

 

[skyungjae]

In this page:

http://bikemotive.myshopify.com/collections/ebike/products/freewheeling-crankset-for-ebike-bikemotive

What is the best combo for the gng kit? And which model of central movement should I use with it?

BR,

- Fabio

What are you trying to accomplish over what the GNG already comes with?

 

[mwkeefer]

Hi Kifukarider

I have done zero miles with the stock GNG setup, strange as it may sound, I want to improve it before I have even used it!

I have a different motor setup at the moment and want to fine tune that one first, then do a back to back comparison.

The GNG is back in a spares box but ready to install if I break the current Astro 3210 setup.

I had already started down one road when the GNG kit came out so now it is a plan B of sorts, it will see active duty at some point though.

I hope this makes sense.

Dude!

Really, you have an astro 3210 in place of the stock motor?

Details please (as I've given this thought for my gen #1 with a modified bracket)... did you use the front and rear (or right and left) motor face plates and make the astro fit? Or did you do something different?

Presuming you have it as spare I'd guess you adapted the face of the motor to mount the Astro 3210 - some pics would be great, turn count, voltage you will be running, sensors or no?

Personally I modified mine in a few ways so far (1.0) before realizing that properly done the 3210 would be a better solution for 1500w - I have a pair of 3210 10T with a kV of 135 so I plan (if I go ahead)... in my case I would have to limit to 5S to mate up with the stock 20.9xx : 1 reduction (assumption 120 RPM no load @ 18.6v or 5S Lipo Nominal)... this is a bit lower voltage than I like to run with a full charge of 21v (wow, I need to hit Jeremy Harris Up) and the power level in theory would be somewhere about 60A continuous and maybe 100A peak for about 30-60 seconds without thermal issues so average power of 1260 watts and nominal power of 1110 watts on same 5S. Peak powers would be 2100w and 1850 respectively which is quite useable, the only issue I have run into in my plan is that only puts the Astro at a maximum RPM of 2514 which is 1/3 of it's most efficient speed of 7500 RPM - the one thing holding me back from attempting it since I can't get anyone at astro to even guesstimate what running that wind at such low speed and voltage would cause.

As Matt aka Recumpence told me many times - it's the high RPM geared down that allows these to develop maximum efficient power.

That in mind, torque is another concern - at 60A with my Astro 3210 winds the kV/kT calculation of 1355 / kV yeilds 10.037 in oz per amp at the shaft, presuming 60A continuous but 100A peaks (off the line surge) that equates to: 602 in oz at 60A and 1003.7 in oz at 100A which seems not so big until we put into measurements most people get - FT LBS, so 60A = 3.1354 ft lbs torque @ shaft and at 100A it means 5.2276 ft lbs peak. Add in the reduction and it's 20x or 62.708 ft lbs torque at the crank and at 100A a full 104.552 ft lbs of torque.

Presuming you've selected a lower kV Astro you will have a higher kT so your torque values will change, figure them yourself:

1355 / kV = kT in inch ouches
kT * Reduction = inch ounces at crank
inch ounces at crank / 12 = foot ounces at crank
foot ounces at crank / 16 = ft lbs at crank

My concern would be for mounting flex of the stock setup.

Again please share your details

-Mike