New Powertube battery doesn't quite deliver

Amazer98

Active Member
Region
USA
City
Yarmouth
So... this is my first new thread on this forum. I've been lurking on EBR for a few weeks, learning what I can about bikes, batteries, best practices, realistic expectations and so forth. Bit the bullet a few days ago and ordered a Bulls Grinder EVO speed pedelec, which I picked up yesterday at Electric Bikes of New England in Londonderry, NH. The bike is basically great, handles very nicely and is fun as hell. I'll write a review in a few days after I have a little more riding under my belt.

I'm putting this thread in the Bosch bucket, as my question has more to do with Bosch batteries (or maybe lithium ion ones in general) than Bulls bikes. Here's the thing: the EBR review of the Grinder EVO claimed the estimated maximum range is 85 miles on this bike. I confirmed this a couple of weeks ago when I called Bulls CS in California. The bike has the 500wh Powertube battery-- the same as the Giant Road-E Pro, on which some riders were claiming they got almost 100 miles per charge.

Anyway, the dealer fully charged the battery before I picked up the bike. But when we turned on the Purion display, setting the level to ECO, the bike-estimated range was just 46 miles. The dealer said that after several initial charge cycles, the battery life would improve significantly, adding that Bulls had also revised its software to be more conservative in its range estimates. Whether these claims prove to be true, only time will tell.

What I can say is that after two rides totaling 46 miles, my battery claims it has only 2 miles range left on it. I went down to my last bar (Purion displays only 5 bars of power like a cell phone) when it read 4 miles left, which I thought a bit strange. So, needless to say, I am disappointed with the battery range.

I rode more than 90% in ECO mode over moderately hilly terrain in central NH (near Manchester) and coastal Maine. The hills typically didn't exceed 100 or maybe 150 feet-- we're not talking the White Mountains. I used the Tour setting (#2 out of four power assist levels) sparingly on a few hills, since I couldn't resist checking out the extra oomph. Still got a great workout, as I pedaled almost as hard as on my road bike... just went faster.

But I am shocked that my cool Powertube battery is pooping out so quickly... and can't account for how anyone could claim the max is 85 miles. Only if they're talking about one very, very long descent!

Also, my odometer seems to be overstating distance by more than 5 %. A 22 mile ride is really 20.5, according to my friends' calibrated Cateyes. What's up with that? You'd think Bulls would know how to program the system to their selected tire sizes.

I welcome all comments and opinions!

Andy
 
My wife has a Raleigh ebike with a bosh 500wh battery. It always says 45 miles in eco on the estimator but she gets easily 80 miles with the way she rides. I'm in Las Vegas so pretty flat and she uses no assist a lot of the time with eco and turbo mixed in. You live in a moderately hilly area so 46 miles sounds pretty good to me. Your weight, wind and hills all factor in on your mileage so I don't even know why company's even put a range on there ebikes, but you can bet it's done with a light weight rider with no wind and a slight down hill.
 
For lithium batteries when they are first new, deplete fully about 3 to 5 times, fully allowing them to re-charge over night each time. Your capacity will be maximized as the cells get better balanced.
 
estimated maximum range is 85 miles on this bike.

This is complete BS.
Using Bosch Gen 2 speed motors , you consume ~15whr/mile (from my experience of over 7500 miles on them). 15 whr per mile is a very decent figure for Bosch speed motors.
So, on my bikes with 500whr battery, I get about roughly 35 miles of range before the the battery quits.

my odometer seems to be overstating distance by more than 5 %. A 22 mile ride is really 20.5, according to my friends' calibrated Cateyes. What's up with that? You'd think Bulls would know how to program the system to their selected tire sizes.

This has been discussed in detail. Please refer here: https://electricbikereview.com/forums/threads/is-bosch-off-on-its-speed-calculations.24345/

the same as the Giant Road-E Pro, on which some riders were claiming they got almost 100 miles per charge.

Yamaha actually has slightly better efficiency but 100mile /charge is possible only if the rider input was significant and the average speed was <18mph.

In summary,

45miles = good range on a 500whr battery. You would not get more unless you do most of the work.


adding that Bulls had also revised its software to be more conservative in its range estimates.

Bulls has no control over Bosch software. Real world experience will tell you differently from what you read on the forums.

Looks like you had extraordinary expectations reading online stuff, and I feel those expectations are not realistic. Chalk it up to marketing blurb that you did not read correctly.

Overall, 40+ miles is decent for a 500whr pack.
 
Also,

I have found the Bosch range estimator to be very accurate.
You can use this tool: https://www.bosch-ebike.com/us/service/range-assistant/

It predicted my range accurately for a 500whr pack. Check this out

1566771944171.png
 
Also,

I have found the Bosch range estimator to be very accurate.
You can use this tool: https://www.bosch-ebike.com/us/service/range-assistant/

It predicted my range accurately for a 500whr pack. Check this out

View attachment 37182
And there's a total of 14 different factors in that calculation!
1 of those factors is "Season", Aussie Summers & Winters are different to European in terms of temperature which would be a large factor i think.
How long is a piece of string?
 
1 of those factors is "Season", Aussie Summers & Winters are different to European in terms of temperature which would be a large factor i think.

The original poster clearly mentioned he picked up the bike from a store in New Hampshire here in the US. [see below]
We still have warm temperatures ( or pleasant temperature). And I can assure that Bosch range estimator tool works very well.

How long is a piece of a string? = the devil is in the details.

which I picked up yesterday at Electric Bikes of New England in Londonderry, NH. The bike is basically great,
 
First things first: a piece of string is generally considered to be 3 feet long. There, settled! 😎

Next, thank you everyone, for chiming in with your comments. I want to say that this site is great-- there are obviously many knowledgeable folks here who are well-versed with e-bikes. And somehow the personal snipes and occasional vitriol that one sees in other online forums-- even cycling ones-- is not present here. EBR bucks the trend in snarky online communications, so congrats on that.

So, I started following Deleted Member 4210' advice and charged the Powertube last night (had to do that anyway). Today I went for a 26 mile ride and saw some improvement in battery life. The display initially promised me only 43 miles in ECO mode, but after pedaling more sedately at 14-15 mph on average, after 13 miles or so, I could see my range estimate steadily increasing. I ratcheted up my pedaling into aerobic territory for the second half of the ride.

After a total of 20 miles, I had 39 miles remaining in ECO mode. I kept the bike in ECO mode until the very end, where I had a half-mile of continuously rolling hills followed by a half-mile of a moderately steep climb, so I threw the bike into Sport mode for the hell of it.
In that one mile, I burned off about 4 or 5 miles from my estimated range, so I can see how tapping the higher assist levels really drains the gas tank, so to speak.

Still, the increase today from a 43-45 mile range to one in the upper 50s was great to see. Even if it holds steady at this level, I'll be satisfied. Maybe a few more charge cycles will help.

Ravi wrote:
Looks like you had extraordinary expectations reading online stuff, and I feel those expectations are not realistic. Chalk it up to marketing blurb that you did not read correctly.

I don't think this is quite a fair assessment. I got the maximum range estimate of 85 miles from the EBR review, which clearly used the specs that Bulls gave. A spec sheet should not be marketing propaganda... but maybe I'm naive on this point. Anyway, I corroborated this number with Joaquin at Bulls, who is one of their technical reps. When I used the Bosch range estimator that Ravi sent the link to above, the only way I could achieve 85 miles was to input my cycling speed as 8 mph. If that is how Bulls got that number, I will say only that that's not quite copacetic.

Well, live and learn. I'm enjoying the bike and getting the same cardio workout... only going faster and having more fun!
 
A spec sheet should not be marketing propaganda... but maybe I'm naive on this point.
And yet, sadly they are! There are to many variables for ANY estimate to be realistic, at least that's my experience. My 120Lb wife gets further with an 11Ah battery than I do at 220lbs with a 17Ah battery. Add topography, wind, tire pressure, etc.and the numbers are all over the board.
 
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