cwah
100 MW
Yeah try 15s
lluviaperro said:Thanks for all the advice, yes the motor works normally when I discharged my back below the 62v cutoff. Has anyone else had any experience with over volting this motor? I expect efficiency would go down, as well as potential for damage to the motor itself. The 30 amp limit of the controller with 60v would be 1800W. In addition I would be running the stock "sunflower" chain ring on a 29er with the intention of climbing hills so keeping the speed of the motor up might be an issue.
What about damage to the controller? As voltage goes up current goes down so not anticipating a problem with frying it but this is new territory for me.
Kory
Alan B said:The BBSHD is quiet and makes good thrust for its power level. It is not a superbike compared to the big hubs like the Cromotor. But it is a quick easy install, doesn't add a lot of cables, boxes and tiewraps to your bike. On a steep hill on pavement it is power limited, in the dirt the speed you need is not so high due to the terrain so the power is more than enough, but on pavement you can run out of power. Shift into a low gear and you can move along far faster than the pedalers and low powered ebikes, but the high powered hubs are going to leave you. Generally I can get to 25 or more on pavement, but in steep terrain it can be less. You get the most power when you let it work at high RPM so the pedal cadence will be very high. This makes it difficult to add leg power. If you are adding significant leg power then you're probably not in the right gear and your not getting max power from the BBSHD. Pedal cadence should be well over 100 RPM at the max.
The BBSHD is a great kit to keep your bike feeling "bike like" and adding a large dose of epower. If you want a racing machine to keep up with traffic on the street you'll probably want a much bigger motor. But your bike won't be light and "bike like", or it won't be quiet or look stealthy. At the moment anyway, all the higher power alternatives are either noisy, heavy, big, visually intrusive or a combination of the above.
I've written up my experiences here:
https://endless-sphere.com/forums/viewtopic.php?f=28&t=78722
I'm getting 25 miles range when flogging it hard, and probably about 50 miles range when riding it easy (I haven't done a full pack riding it easy to verify that though). That's with a 52V 20AH pack. Clearly if you pedal enough the range can be anything. Those ranges are with minimal pedal work input. Not that I didn't pedal, but I didn't put much energy input, and let the motor carry the bike. Total up weight around 250 pounds.
For a daily commuter, I built up a Greyborg frame with a Cromotor and 32 amp hours of 18S Multistar lipo. That will go up a 15% grade at 25 mph, and compete with the cars at modest street speed (I didn't install enough voltage to go too fast, this is not a motorcycle). No chain wear (from the motor) and tough heavy moped tires for minimum flats. But it makes a heavy bike and out of place on any separated bike path. That story is also linked in my signature below.
If you are not getting enough range with the BBSHD there are three choices. Pedal more, or mount a larger or additional battery. If you want more speed, optimize the gearing but don't expect to reach 40 on the steep hills. That would take more power than is safe through the BBSHD. If you put a lot more power through a bicycle chain expect a lot of maintenance.
Good luck with your project, and Ride Safe!
Woodytx said:Thank you, that is very thorough and seems consistent with my experience. I will try higher cadenced pedaling for sure. My battery is 52V 11.5A which explains the much shorter life.
I don't understand these guys claiming 45+mph and 30 on the hills. It's not possible at factory settings, you can tell within moments of hitting the throttle for the first time.
Alan B said:I mentioned the Cromotor just as an example of a serious commuting machine that I have a lot of experience with.
Pedaling my Cromotor setup is not practical due to the lack of gearing, if I had a wider frame with full mountain bike gearing it would be like pedaling any other heavily loaded cargo bike, possible but slow. However with 2kwh the range is such that non motorized pedaling is infrequent. There's enough capacity to easily make my (ex) round trip commutes with room to spare, even with a 26 mile 1800 feet climbing (and descending) route.
The Cyclone 3000W is noisy, and if you ran it at full peak Cromotor power (6KW+) the chain would blow out shortly if not instantly. so it is not in the same league either. For a commuter it would be too high maintenance, in my opinion, eating chains and brake pads every few months. With powerful ebraking on the downhills, the CroBorg doesn't need brake pad changes, even with years of use. The maintenance consisted of rear tires, which it consumed in about 3000 miles, and cheap freewheels which it consumed at the same rate. A better freewheel would fix that, but it would require some machining to make a White Industries unit fit. That's the way I like my commuting machines.
If you want a higher power mid drive the Cyclone is a low cost choice. But it doesn't compete with the BBSHD for ease of install, quiet operation, clean looks, minimum wires, tiewraps and boxes on the bike. The BBSHD is way ahead in maintaining a bike-like look and feel.
This thread is primarily about the BBSHD and the present topic is what the realistic performance is, and is not. It depends somewhat on the bike, the gearing and the rider weight. The rider input can make a difference in the short term, it is not too hard to pedal at the 600 watt level for a short burst, but at the longer term 200 watt level the performance is dominated by the motor. The best cadence for maximum output from the BBSHD is pretty high which makes it hard on the rider to contribute much. If you have the right gearing and can keep the BBSHD in the powerband at high cadence rates it will go fairly fast, but on my Diamondback I run out of gears on the high end with 42:12. You don't want to go below 14 teeth at this power level so a larger chainring would be required, and this would reduce the climbing capability that I got it for, so this is not something I'd pursue. If it gets to 30 or a bit over that's plenty for a mountain bike that can climb a tree, in my book. And it does that, easily. When it gets steep it becomes power limited at some speed, so do I - only my limit on a steep hill is less than 5 mph whereas the BBSHD gets to about 15. There's only so much you can do, it just takes power to climb hills. I suppose losing 100 pounds would make a big improvement, but that would put me way below my weight target and would not be healthy.
In any case 40 seems like a speed reached on a downhill rather than level. At least with my BBSHD. Thirty something on the flats I have seen. But around here it is hard to tell slight uphill from slight downhill from level. At least on most of my rides. Plus you need good surface and plenty of room. The surface roughness makes quite a difference. I'm running 30 psi in my mountain bike tires, so not very good for those speed runs.
If a little more performance is wanted, the Cyclone is a contender. But you have to give up a lot in visual and acoustic stealth. Everyone has different requirements. Folks with a bicycle background may feel the BBSHD is too much weight and power. Folks with a motorcycle background may feel it is too little. In reality it is capable of more power than legally allowed for an ebike almost anywhere on the planet. If it is set for legal power levels the BBSHD is very reliable and can generate this power silently and at low cadence rates comfortable for pedalers. So it is good for those who want to pedal and contribute but combine with epower at the legal limit. It can also be operated at higher power and cadence levels. But it is not a 3000 watt machine. Not the way it is built now. But it is reliable and quiet the way it is.
Woodytx said:I have read numerous posts (here and elsewhere) about 40+ mph speeds on flats and there is just no way mine will do that. I've reached 35+ mph with full throttle/PAS 5/hard pedaling and a decent stretch to build speed. On a relatively steep hill I can maybe go 15 mph.
Woodytx said:My 52V battery lasts about 12-15 miles with moderate throttle and PAS, which seems short compared to the 20-40 mile estimates I had read about. I weigh 180 lbs and ride a decent hybrid; fitness and cycling experience are well above average, so it's nothing extraneous.
tychay said:Curious what other people's numbers are also, but some things to note:
...
This person is reporting ~30WH/mile and is getting ~35miles with a pack that is almost 2x that of a typical Dolphin/Shark. He is getting 26miles on the low end so if your terrain is hilly and you have a shark pack, 12-15 doesn't sound out-of-sorts.
Hope this helps!
rs4race said: