Wh/mile vs. riding range for a battery

[ZeroEm]

Sometimes I ride with hard core bikers, they really impress me. I'm sure you fit into that group, like a riding friend he's around 65 now. He tells me stories of 150 mile rides. He can not do that anymore, I've never been as good as he is now. He still rides for his knees.

When I built my trike it was so I did not struggle up hills and need to charge every time I ride. So I pedal as much as possible, the trike does almost all the work on the hills. I bought bigish batteries, big for some, small for others. 72V, 24ah have two but only run one currently. How far I go depends how the trike is treated.

I'm not much help to the trike above 20 mph, my motor's sweet spot is at 15 mph. Another fact you can get more watts from a battery if you keep the amps low.

E-bikes are a god sent as we age. you could do a high racer or mid racer, E-bike. Billvon is the one I worship, he has test different configurations, on many different road trips in the mountains. Here is his website https://mrbill.homeip.net/index.php
He tries to get as much as he can out of a battery.

 

[markz]

That is so true, its so much more fun riding an ebike because
- we can go to more places that we wouldnt otherwise go = EXPLORING
- we take routes and paths that we would never do before = EXPLORING
- we go further, in a faster time then we would non electric
- we have more fun because we aren't exhausted by pedaling

Picking the proper power setup for what you want is the key.
Like for me I like to hit certain hills knowing what kind of a workout its going to be.
Certain hills you gotta go flat out all the way up
Other hills you can half ass it then half way up dont even bother pedaling and still make it up

Around my city, mid drives aren't needed. The most one could go would be 45H hub motor 3kw with fins and Statorade and you could do a back to back steep hill depending on the power, say 72V 70A and 300lbs could probably get up the steepest of steep hills and do it twice, 3 times you'd need to dunk the hub in the river to cool off.

I can still push pretty hard on hills but not like when I was younger. Just keep losing more top end VO2 with age. As you note the big difference is humping over the tough hills. In the past it was much easier and I had reserves left... now closer and closer to the margins, if not hitting the wall altogether on faster climbs. The e-bike is like magic to ease the load just enough to make it more fun... or totally if I get really gassed in this ungodly heat. These things are fun.

 

[raylo32]

Did another ride on my TSDZ2 bike today, level 3 (of 5) assist, 29.5 miles, 1400 feet climbing, 21.3 mph average speed. I used 63% of my 625 Wh battery which is 393 Wh, or 13.3 Wh/mile. My bike does not have a throttle and I was doing a moderate human input, nothing extreme. Unloaded terminal voltage on my 52v battery was about 49ish. I would feel OK with going maybe down to 30% battery... with that and if I were to take this bike on one of my group rides and hold it down to human speeds which on these typically average 17 mph or so, I am guessing I could get about 40 miles or 45 miles tops. So if I do this I will definitely take my range extender. I should do a test keeping to a 17 mph average but that just wouldn't be fun! This motor on OSF and bike are performing flawlessly.

 

[raylo32]

Yes, at 68 YO those 100+ days are mostly over for me, too, as are long tours in the Rockies or Alps. Although I have friends even older still doing that. Oof. I could probably train up and do a normal not too hilly century but I just don't like to suffer that much anymore and my knees and hips ain't what they used to be.

What you said about e-bikes being a godsend as we age is spot on. Just so much fun and not feel like a used up dishrag after every ride. I have the OSF on my TSDZ2 and set the speed limit to 35 mph... but the cadence gets too fast to maintain for long at much over 28... and that much wind resistance really sucks the battery Wh. But no need to beat on the motor that hard... Like the ride I just described above, just about perfect. Nice and fast, good range, speed up the hills is fast enough to stay reasonably cool. Just fun, fun, fun.

Sometimes I ride with hard core bikers, they really impress me. I'm sure you fit into that group, like a riding friend he's around 65 now. He tells me stories of 150 mile rides. He can not do that anymore, I've never been as good as he is now. He still rides for his knees.

When I built my trike it was so I did not struggle up hills and need to charge every time I ride. So I pedal as much as possible, the trike does almost all the work on the hills. I bought bigish batteries, big for some, small for others. 72V, 24ah have two but only run one currently. How far I go depends how the trike is treated.

I'm not much help to the trike above 20 mph, my motor's sweet spot is at 15 mph. Another fact you can get more watts from a battery if you keep the amps low.

E-bikes are a god sent as we age. you could do a high racer or mid racer, E-bike. Billvon is the one I worship, he has test different configurations, on many different road trips in the mountains. Here is his website https://mrbill.homeip.net/index.php
He tries to get as much as he can out of a battery.

 

[raylo32]

I took my TSDZ2 Cannondale F1000 on a short club ride a few days ago and it performed flawlessly. 36 miles, 2500 feet of climbing, one 4 mile climb with a section of 14% grade... no problem. It was kind of fun to have a chat with a fellow e-biker on that climb whist the others were gasping.

As for the battery... GA cell shark pack with advertised 13.6 Ah capacity. Started out at 57.6V, finished at 52.5V so I had plenty of capacity and did not need to switch to the EGO aux battery I had in the rear rack. The slower human pace on the hills and flats surely kept it easier on the battery than my normal fast solo rides.

I need to find some detailed SOC tables (rather not have charts) for GA cells and for Q cells (my other pack) to really get a better handle on SOC and range.

 

[ZeroEm]

raylo32 you will get the hang of it. Do both slow and fast rides then you can regulate how fast/far you can go with so much effort.

Longer rides start out conserving power then when half way have a good idea how hard it can be pushed. Have one ride that is a low grade climb for 20+ miles, much easer on the way back. When I head south slight down hill headed toward the Gulf Coast and i'm always surprised how much it takes on the way back, not counting getting tired.

Have a larger chain ring now for the road will see if that helps. always want to ride faster on the road but my cadence is lacking. Small hills here but over 20-50 mile the elevation changes enough that it has a noticeable impact on watts.

 

[Blacklite]

I am a retired engineer, not electrical, so while I am not an expert I do understand the basics and the math. One thing I am struggling with is how to determine the ultimate range I can get out of my battery that I of course know depends a lot on speed, assist, terrain, etc.

I have a bike with TSDZ2 running OSF that graphs out running Wh/mile on the display. My battery is 14s/52v, 12 Ah which equates to 625 Wh. On a recent ride I started out with a 85% soft charge to about 56.6V, rode about 35 miles and finished with an unloaded voltage of about 43V. I repeated the soft charge and my Grin reported putting in 8.1Ah which equals about 420Wh. The Wh/mile graph varied from zero to a peak of 8 and guestimating the overall average might have been ~4. So if I was really only using 4 Wh/mile that 400 Wh should have taken me 100 miles... which I know is never gonna happen. What am I missing here? Is the display under reporting Wh/mile, or what?

Remembered this thread after seeing Mbrusa’s latest firmware build, with a fix for incorrect reporting of the Wh/mile vs Wh/km. Might be worth looking at a firmware upgrade.

 

[raylo32]

Sounds good, thanks for the tip. I guess it is time to install C.3

Remembered this thread after seeing Mbrusa’s latest firmware build, with a fix for incorrect reporting of the Wh/mile vs Wh/km. Might be worth looking at a firmware upgrade.