Mid drive and cadence upper limit (top end).

[tomjasz]

I'm familiar with all of Karls' articles. I'm not sure what the point is? I mean that in a friendly manner. Karl simply copied and pasted the same general spec from Bafang.

EDIT

BTW that's a prerelease article from Sept of 2015. It was not released with the upgrade 3077 FET's

 

[Trail Cruiser]

I'm familiar with all of Karls' articles. I'm not sure what the point is? I mean that in a friendly manner. Karl simply copied and pasted the same general spec from Bafang.

EDIT

BTW that's a prerelease article from Sept of 2015. It was not released with the upgrade 3077 FET's

I think our discussion drifted a little bit. I posted this topic

" Mid drive and cadence upper limit (top end)."

addressed to Court Rye since he always mentioned that many mid drives have lower top ends (80-90 RPM) and when you want to pedal faster, the assist is not there anymore, He always praised the Bosch mid drive for having a higher top end. From my research, the Bosch has a top end of 106 RPM and after that there is no motor assist.

However, that preconceived notion does not apply anymore to the newer mid drives especially the Giant ebikes with the Synchdrive which actually has a much higher top end than the Bosch (120 compared to 106), but Court continued to say that the Giant has a lower top end, unlike the Bosch. I mentioned in the post, that in order to be objective, he has to check it with a cadence meter where the Giant ebikes have cadence meters (as standard feature) on their display panels to begin with (why not use them?).

That preconceived notion also does not apply to Bafang mid drives since the BBS02 has a rated cadence of 120 RPM and the upgraded BBSHD is rated at 130-150 RPM. I can attest to the BBSHD since I checked it myself with my cadence meter while I throttled it on a bike stand.

I understand the comments stating that it's not an issue since most (casual ebikers, non athletes) rarely pedal above the top end anyway. But that is not the main issue of the thread.

For me, it is better for the motor to outrun your cadence than the other way around. If you outrun the motor, you lose power assist and you lose speed and momentum.

There are road bikers and other riders (including me) who pedal at higher cadence on a regular, non powered bicycles. And we want to be able to do the same thing (high cadence) on ebikes (to have a more bike like experience). What's wrong with that?

I, for one, saw 140 on my cadence meter while riding my hub driven ebike when I passed a bunch of fast road cyclists on a hill. For me, I should be able to do the same thing on my mid drive (which I can on my BBSHD but not on my TranzX).

Addendum:

Current Bosch has assist at cadence up to 120 (Performance line) and 100 (Active line).
https://www.bosch-ebike.com/en/components/drive-unit/

Giant Synchdrive has assist at cadence up to 120 (Syncdrive Pro) and 100 (Syncdrive Sport & Syncdrive life).
https://www.giant-bicycles.com/us/syncdrive

 

[tomjasz]

Yeah, I'm a drifty sort a fella. But curious about the Bosch. I'm planning on getting a used bike with Bosch, gut tells me no, or a Shimano. Several popped up last season with very low prices and difficult batteries. Having all the needed tools to rebuild a battery gives me the courage. My only concern is parts for the motors...we'll see. Howz THAT, for a drift. VVBG!

Ride safe!

Tom

 

[JRA]

"For me, it is better for the motor to outrun your cadence than the other way around. If you outrun the motor, you lose power assist and you lose speed and momentum."

This is the exact opposite of what works and feels the most natural to me and why I prefer to not use PAS and a throttle instead. By keeping my human pedaling effort separate from motor output I find pedaling slightly over the top of the motor in the appropriate gear ratio and regulating the motor output via the throttle gets me the best combination of desired speed, torque and wh/mi but that is with a direct drive hub motor. It also allows me to go up or down a gear while in cc mode varying my cadence to break the monotony of churning out road miles.

Which is drifting even further but after seeing this thread it makes me even less interested in PAS for my needs. Guess I am stuck being a Class II citizen.

 

[emco5]

... cadence RPM.... Bosch used to have favorable feel since the cut off is 106 RPM... assist cut off in Yamaha, Brose, and other popular OEM brands are in the 80-90's RPM....Giant ebikes since they now use the new Syncdrive that has higher cadence cut off of 110-120 RPM.....

So, does anyone know the cadence peak for Shimano's E6000 Steps system? Maybe I missed it, but none of their tech data I've gathered appears to list it.

 

[Trail Cruiser]

May I ask where you got the data about the Yamaha PW series drives cutting off assistance at 90 RPMs?

.." With any mid-drive there is a range of cadence or pedal rpm where the assist provides the best support. If you pedal too fast, you feel the assist fall off. The Yamaha assist is supposed to stop at 80 rpm, but to us, it felt happier at 65 rpm. The Bosch has a wider and less critical range of pedal rpm. "...
http://www.electricbikeaction.com/bike-comparison-haibike-sduro-trekking-rc-vs-xduro-trekking-rx/

 

[Trail Cruiser]

That was an interesting read, but the conclusions are based on subjective opinions. Below you have a snapshot of my Power Meter and Cadence Meter. The Power Meter shows 5 bars meaning that the drive is providing a good level of assist, and at the bottom of the screen we can see that my cadence is 101 RPMs. It keeps on providing assistance above that cadence too. You can clearly hear the drive at higher cadences.


View attachment 16122

That's a nice display with built in cadence meter. That's a good information to know. On my 2015 Tekoa with a TanzX mid drive, the top end varies with the assist level. PAS 1 is 80 RPM, PAS 2= 86 RPM, PAS 3= 90 RPM, and PAS 4 is 100 RPM.

 

[Dan.Shaner]

Hello friends. New to site. I have a bbs02 on a Civia Hyland with Alfine-8. It’s a commuter.

Gear sense is mandatory for this setup, as is tuning the program. I’m hoping for a bit of insight...

Programming is easy, knowing what to use, less so.

I reduced my start current to one amp per many recommendations. Works beautifully.

I reduced my max current from 25 to 18, which may have been a touch too low, but makes for a wonderful, not over-aggressive assist.

Here is the interesting part. At each assist level, 1-5 in my case, the motor cut-off is at a different speed, measured from the speedometer. Hmm. Why?

Out of the box, I’d set assist level to one, and at perhaps 13mph, the motor begins to resist my pedaling. Pretty abruptly, and at perhaps 80-90 rpm—too low. At level two, the cutoff is perhaps 18, at 3, 22, etc.

How might this protect the motor? I’m not sure.

So, I changed the power cutoff to essentially not happen. Note my max speed is still governed.

Now, it rides like a dream. I find that I ride at assist level 1-2 nearly all the time and cruise at 19-25mph. I have a low current draw at level one, and it assists up to max speed, or as fast as I can pedal. Feels very natural. At level two, I get the same smooth power all the way up but with more assist.

So far, no problems. Am I asking for them?

I’m thinking that, when cycling at 14mph, I’m not “helping” the motor by increasing assist level, so changing the point of assist cutoff won’t hurt it.

Of course, I don’t know. That’s why I’m writing.

One more thing. I moved to a smaller rear cog on my Alfine, so I have a more natural high gear. It is important to be in a low gear at start, and the low current start up and max current limitation seems to work nicely with it.

 

[MLB]

"For me, it is better for the motor to outrun your cadence than the other way around. If you outrun the motor, you lose power assist and you lose speed and momentum."

This is the exact opposite of what works and feels the most natural to me and why I prefer to not use PAS and a throttle instead. By keeping my human pedaling effort separate from motor output I find pedaling slightly over the top of the motor in the appropriate gear ratio and regulating the motor output via the throttle gets me the best combination of desired speed, torque and wh/mi but that is with a direct drive hub motor. It also allows me to go up or down a gear while in cc mode varying my cadence to break the monotony of churning out road miles.

Which is drifting even further but after seeing this thread it makes me even less interested in PAS for my needs. Guess I am stuck being a Class II citizen.[/Q

And I have throttles on 2 of my bikes and next to never use them because I much prefer the more bike like experience with PAS. LOL
Different strokes.................

 

[tomjasz]

Hello friends. New to site. I have a bbs02 on a Civia Hyland with Alfine-8. It’s a commuter.

Gear sense is mandatory for this setup, as is tuning the program. I’m hoping for a bit of insight...

Programming is easy, knowing what to use, less so.

I reduced my start current to one amp per many recommendations. Works beautifully.

I reduced my max current from 25 to 18, which may have been a touch too low, but makes for a wonderful, not over-aggressive assist.

Here is the interesting part. At each assist level, 1-5 in my case, the motor cut-off is at a different speed, measured from the speedometer. Hmm. Why?

Out of the box, I’d set assist level to one, and at perhaps 13mph, the motor begins to resist my pedaling. Pretty abruptly, and at perhaps 80-90 rpm—too low. At level two, the cutoff is perhaps 18, at 3, 22, etc.

How might this protect the motor? I’m not sure.

So, I changed the power cutoff to essentially not happen. Note my max speed is still governed.

Now, it rides like a dream. I find that I ride at assist level 1-2 nearly all the time and cruise at 19-25mph. I have a low current draw at level one, and it assists up to max speed, or as fast as I can pedal. Feels very natural. At level two, I get the same smooth power all the way up but with more assist.

So far, no problems. Am I asking for them?

I’m thinking that, when cycling at 14mph, I’m not “helping” the motor by increasing assist level, so changing the point of assist cutoff won’t hurt it.

Of course, I don’t know. That’s why I’m writing.

One more thing. I moved to a smaller rear cog on my Alfine, so I have a more natural high gear. It is important to be in a low gear at start, and the low current start up and max current limitation seems to work nicely with it.

AS long as you are not overheating or lugging the motor you should be good. BTW have you discovered the Penoff programming? It's quite an improvement IMO.
https://penoff.me/tag/bafang/

 

[tomjasz]

Yeah, I'm a drifty sort a fella. But curious about the Bosch. I'm planning on getting a used bike with Bosch, gut tells me no, or a Shimano. Several popped up last season with very low prices and difficult batteries. Having all the needed tools to rebuild a battery gives me the courage. My only concern is parts for the motors...we'll see. Howz THAT, for a drift. VVBG!

Ride safe!

Tom

UPDATE, even though disabled I like to pedal. I decided to move on and have sold all three BBSHD motors. They made for more of a moped than bicycle. I decided on MAC motors and Thun a torque sensing axels. Still looking for that Bosch, but am looking for that "garage find" super deal. Or maybe the Yamaha. The best part of Bafang was the ability to send service. My only disappointment with Bosch. All of my fast bikes have been sold or detuned. I found that traffic was more likely to make for judgements on my speed and cut me off when I'm traveling more than 25MPH. My days of fast electric bikes are over. I'd still build a fast MTB for the trails if I were able enough. Silently cruising the hills and dales makes for some incredible wildlife sightings and experiences, on the few such trips I've taken.