I was quoting Carl Sagan who was a promoter of critical thinking among other things.
5 Likes
thanks for the feedback!! any issues with the ESC?
Not that I can recall. It still works, i rode it few days ago. 
Thats beacuse most hubs have crappy urathane. We did a roll test today and 4wd V3 carvons out rolled a dual 6355 board without a doubt.
On a 10 mile leg of the 20miles we rode today, my 4wd Carvon board averaged 13.2 whr/mile which was lower than the belt drives consumption which was closer to 15.
The belt drive efficiency claim was not evident during todays ride. Also consider that the belt drive had an 80lb weight advantage and was geared to a much lower top speed. Both boards were 12S and on superflyās and tracking efficiency with the vesc monitor app.
Im gonna go ahead and call this "Direct drive is less efficient " myth debunked for my own purposes, and make a new claim that belt drag causes greater losses than many belt drive users are willing to admit. The data and comparisons we did today have convinced me that most of the losses in hubs have come from rolling resistance from low quality or thin urathane.
I havent heard of any 40mph belt drive boards that will average under 15whr/mile especially not with a 280lb rider on a 10mile trip.
Anyone have evidence to prove otherwise?
7 Likes
This part right here mateā¦
Thatās without even getting into the details of motor wattage etc.
1 Like
Hmmm. Whatās the axle material made of?
Stuff Is generally a lot more expensive here. (Shipping and taxes) The Facebook uk esk8 forum is a good place to start too. Thereās a few guys who might be able to help with a battery pack. I make fibreglass enclosures, but you might want gaffa tape to stay within budget like I did on my first build!
Yep, ive got evidence. 23 minute video of the 10mile ride with all the data overlaid.
I dont think current setting matter if we were riding together at the eqme speed for the same distance. My total current setting are much higher than his anyway.
A 4 wheel drive would draw more current than a dual becaus eyouba re powering more motors that would not increase efficiency but rather decrease it
1 Like
The efficiency on the hubs was really good Iām surprised. For the the first 3 miles we did when I had fresh legs and was more on the throttle I got 21whr/mile + the next 7 mile (~10miles) I got 17whr/mile then by the end of the 19 mile ride I was down to average 14.8whr/mile. So by end of the day I was easier on the throttle and effeciency went up.
You have four hubs that are āgearedā for 60mph unloaded and I have two belted 6355 motors geared for 34mph unloaded and braking I would say I had the edge. But I wonder if you had two hubs wound for my top speed would braking and acceleration be as good. That would get my interest
Was a fun ride. We should do another comparison
1 Like
You know, you have to be careful here. As most of people are using belt driven motors. They donāt like the fact that there are also some advantages with hub motors. Anyone who has had physics at school knows that less moving parts means better efficiency. If Iām not wrong in car industry we have something called horse power, and break horse power. Where horse power is power measured on wheels, while break horse powered is power produced by engine before transmission loss(~15%).
1 Like
There are some advantages to hubs, but efficiency isnāt one of them. True, in a sterile test environment with an unloaded hub vs belt drive at a given RPM, the hub will probably win out due to no losses from the belt. However throw in a load, stop and go traffic, wind resistance, hills, etc and the gearing potential from a belt drive train easily outweighs any efficiency the hubs had over belts.
5 Likes
Yaaay thatās what I wanted to hear. Although both are technically single speed, belt driven systems have an advantage in tunability. The fact you can change your gear ratio to find a sweet spot in efficiency is awesome. IMO the motorās ability to run at an ideal rpm for the majority of the time outweighs the mechanical deficiency of moving a belt around. Besides, belts are very efficient! I love belt driven stuff.
Real talk though I want to see a really head to head comparison. Hubs have great potential but at this moment I favor belts cause theyāre just so much more accessible and reliable overall. Someday when a really solid hub design that can be purchased by the majority of the market I will be impressed
But I think thatās why carvon hubs are more efficient they take concepts from both belt and hub motors, they lack the inefficiencys such as cooling and and bad urethane, but lack the bad parts of a belt drive such as resistance, my single v2 had more range than my single enertion 6374 belt drive, I do agree however though that hubs have a long way to go until they can be better than belt drive but I personally and from what I have actually felt beneath my feet believe indirect drive is perhaps more efficient
What were the ride conditions like during the 10 miles? Lots of stop and go or consistent speed.
There are also a lot of other factors too, belt tightness, use of an idler, how each rider handled the throttle. You may have just been traveling at a more efficient speed for your setup than than the other rider so ā for your use case the efficiency claim may be moot if youāre always in the sweet spot for your setup.
I donāt have evidence myself unfortunately but I get low whr/mile in stop and go city traffic and I accelerate/brake aggressively. I also have low rolling resistance with use of an idler. I am geared lower top speed so itās probably not a fair comparison. Itās really difficult to compare likes here without getting a dyno like @Blasto has. Unfortunately the thread below hasnāt been updated, heās probably too busy.
This statement is very misleading. Try pedaling up a tall hill on a unicycle, then pedaling up a tall hill on a geared bike and come talk about efficiency. Gearing makes a drive more efficient for the load being demanded which is why your car has a transmission in the first place. Weāre not riding in hermetic environment.
7 Likes
belts: subjectively more interesting look still have clearance no axle to break almost no noise in FOC pushing when battery empty entirely possible and not nearly as bad as people make it out to be. loosen your belts a tad.
6 Likes
quote: loosen your belts a tad. I donāt use belts haha. I run hub motors.
whoās blowing VESCS by pushing their boards with it turned off? What cheap shit are you using in there?
4 Likes
So after all that is it belt or hubs???