No Bafang used by mainstream bike manufactures.

[m@Robertson]

My point exactly. Turning up the power 1 or 2 PAS levels (as an option to downshifting) will still leave you with plenty of reserves, without tearing anything up or creating unusual wear, while maintaining your original speed and cadence level.

In fact, I've found this a really good option at low speeds/high loads to prevent stalling the bike with a missed shift.....

Well, in addition to us all riding differently, and thus there being no wrong answers, I'll point out that when I'm riding a cargo bike in the Monterey Bay area, where its all hills and I just changed my drivetrain to a much bigger rear cluster (from 32T max to 46T) because I needed it to do the thing I'm talking about: Maintain cadence up a hill. Its a different cargo bike and that one is set up to pump out a fair bit more power on PAS. Probably around 1000w with cadence probably being about 60 (remember it could be loaded with stuff). And that chain is (I forget exactly) in the 160-175-link range (my BFD is over 200). A power surge rather than a gear change in that scenario is not something I'm so sanguine about, although I certainly do peg the throttle if I think I need it.

However, my Cyc-powered bike is in that same town and that sucker is 4kw with a 216 kart chain as its primary, leading to a second sprocket heading out back on a SRAM EX1 chain. That level of power... No way is a power surge a good idea there unless its on one of the biggest cogs, and that one goes up to 48T although I can only go to the 40T next-to-largest. Worth noting, thats also a SRAM EX1 (tool steel) cluster and its only an 8 speed. Since I can't get to the tallest gear reliably (chain line + front cog size = no go) I have a 7-speed. I don't like it one bit. The jumps between gears are too much along all the lines I have been going over above. So, I have some experience with this next-level power stuff and also with lesser gear counts like what y'all are saying you like.

 

[retiredNH]

Well, in addition to us all riding differently, and thus there being no wrong answers, I'll point out that when I'm riding a cargo bike in the Monterey Bay area, where its all hills and I just changed my drivetrain to a much bigger rear cluster (from 32T max to 46T) because I needed it to do the thing I'm talking about: Maintain cadence up a hill. Its a different cargo bike and that one is set up to pump out a fair bit more power on PAS. Probably around 1000w with cadence probably being about 60 (remember it could be loaded with stuff). And that chain is (I forget exactly) in the 160-175-link range (my BFD is over 200). A power surge rather than a gear change in that scenario is not something I'm so sanguine about, although I certainly do peg the throttle if I think I need it.

However, my Cyc-powered bike is in that same town and that sucker is 4kw with a 216 kart chain as its primary, leading to a second sprocket heading out back on a SRAM EX1 chain. That level of power... No way is a power surge a good idea there unless its on one of the biggest cogs, and that one goes up to 48T although I can only go to the 40T next-to-largest. Worth noting, thats also a SRAM EX1 (tool steel) cluster and its only an 8 speed. Since I can't get to the tallest gear reliably (chain line + front cog size = no go) I have a 7-speed. I don't like it one bit. The jumps between gears are too much along all the lines I have been going over above. So, I have some experience with this next-level power stuff and also with lesser gear counts like what y'all are saying you like.

You should post some pictures, or links to past posts! Hard for me to visualize these setups, but they sound interesting.

 

[AHicks]

Well, in addition to us all riding differently, and thus there being no wrong answers, I'll point out that when I'm riding a cargo bike in the Monterey Bay area, where its all hills and I just changed my drivetrain to a much bigger rear cluster (from 32T max to 46T) because I needed it to do the thing I'm talking about: Maintain cadence up a hill. Its a different cargo bike and that one is set up to pump out a fair bit more power on PAS. Probably around 1000w with cadence probably being about 60 (remember it could be loaded with stuff). And that chain is (I forget exactly) in the 160-175-link range (my BFD is over 200). A power surge rather than a gear change in that scenario is not something I'm so sanguine about, although I certainly do peg the throttle if I think I need it.

However, my Cyc-powered bike is in that same town and that sucker is 4kw with a 216 kart chain as its primary, leading to a second sprocket heading out back on a SRAM EX1 chain. That level of power... No way is a power surge a good idea there unless its on one of the biggest cogs, and that one goes up to 48T although I can only go to the 40T next-to-largest. Worth noting, thats also a SRAM EX1 (tool steel) cluster and its only an 8 speed. Since I can't get to the tallest gear reliably (chain line + front cog size = no go) I have a 7-speed. I don't like it one bit. The jumps between gears are too much along all the lines I have been going over above. So, I have some experience with this next-level power stuff and also with lesser gear counts like what y'all are saying you like.

No cargo bike here, but my 300 lb weight might be noteworthy.....

The reason I went with an Ultra powered bike is because of my size, and because of the hills I'm spending a lot of time in. The hills are of the rolling coastal type. They can be steep, but they are generally not long. Maybe 1/2 mile or so, with some being a little longer.

Point being, I'm no stranger to hills either, and I'm using 4th, 5th, 6th and 7th (of 9) gears 90%+ of the time I'm riding.

A really nasty (steep) hill will generally find me in 4th gear to maintain my speed (9-10mph), and PAS 3 or 4 (of 5) pulling 8-900w.

 

[m@Robertson]

You should post some pictures, or links to past posts! Hard for me to visualize these setups, but they sound interesting.

Well, here's the mid tail on a recent sunup pastry run (pastry in the box, coffee in the flask on the front fork) when I didn't have any panniers on so you can see the drivetrain. I had the skinny-tire'd wheels on as I was replacing a spoke on the normal rims. Chain length on a bike like this with a long cage derailleur to boot is significant.

An older shot with front and rear bags on and loaded. Those rear bags are 80L each and loaded with soup cans, milk jugs, etc. weight - and strain on the drivetrain - is significant.

And the 4kw Cyc X1 with the kart chain drivetrain. Most I have had this one up to currentwise is 60a before I chickened out and lifted. If you pop a bms' peak current limit, you have to plug into a charger to reset it and I didn't want to ride up a long, steep hill if I overdid it. Battery is a custom pack with a spec'd 90a continuous BMS but I don't trust it. This is the motor you would expect to taco a chainring, but the pics I showed above of the BBSHD disprove that (turns out that bike was loaned to a rider who was not given instructions on shifting/riding, and instead of doing that they used throttle power which destroyed the drivetrain).

closeup of the motor. the BAC800 controller and its wires are in the little bag.

 

[retiredNH]

^ Interesting! So the Cyc Motor drive still goes to a derailleur? Must get some interesting drive train wear.

 

[m@Robertson]

^ Interesting! So the Cyc Motor drive still goes to a derailleur? Must get some interesting drive train wear.

Yes, but no more rear drivetrain wear than a normal mid drive. So far. Bear in mind I use steel clusters on top of steel cassette bodies and a ratchet engagement hub with 18-24 pts of contact. So I don't suffer any issues with cassette cogs digging into the cassette body, or the poor cassette pawls giving out under that kind of power. That is a SRAM EX1 rear cluster (11-48T) with tool steel cogs. Its only 8 speed and as such I keenly feel the loss of gear options versus the 11 speed rears I have on my Bullitt and my Surly.

SRAM built that drivetrain under the assumption - the common one - that fewer gears are necessary given the motor. But what I have found is if you are a pedaler, you still want fine graduations of gearing with assist just as you did without assist. Again, its about choosing your preferred cadence and not your speed, or what the motor likes (it doesn't hurt the motor to have these added choices so the gain is all on the rider side with no down side assuming you have strong components). I'm not alone in this. A lot of the higher powered DIY guys swear by 11 spd drivetrains. I thought it was all crap until I bought the Surly and decided to use its original 11 spd setup and realized what I had been missing, with no negative consequences. Chainwise, the 11 spd is stronger than the 8 or 9 (SRAM's 8 spd ebike chain is actually a 10-spd) because of the shorter pins.

 

[Surly]

Yes, but no more rear drivetrain wear than a normal mid drive. So far. Bear in mind I use steel clusters on top of steel cassette bodies and a ratchet engagement hub with 18-24 pts of contact. So I don't suffer any issues with cassette cogs digging into the cassette body, or the poor cassette pawls giving out under that kind of power. That is a SRAM EX1 rear cluster (11-48T) with tool steel cogs. Its only 8 speed and as such I keenly feel the loss of gear options versus the 11 speed rears I have on my Bullitt and my Surly.

SRAM built that drivetrain under the assumption - the common one - that fewer gears are necessary given the motor. But what I have found is if you are a pedaler, you still want fine graduations of gearing with assist just as you did without assist. Again, its about choosing your preferred cadence and not your speed, or what the motor likes (it doesn't hurt the motor to have these added choices so the gain is all on the rider side with no down side assuming you have strong components). I'm not alone in this. A lot of the higher powered DIY guys swear by 11 spd drivetrains. I thought it was all crap until I bought the Surly and decided to use its original 11 spd setup and realized what I had been missing, with no negative consequences. Chainwise, the 11 spd is stronger than the 8 or 9 (SRAM's 8 spd ebike chain is actually a 10-spd) because of the shorter pins.

One of the few voices on here to listen to as ever.

I swapped my box prime 9 for SRAM X01 precisely because of the issues in your two previous posts, namely cadence and i prefer XD to HG, more inherent torque resistance and being a 1 piece cassette. I think it's the best move i made tbh, however i'm not sure the SRAM cassettes are strong enough, time will tell.

 

[retiredNH]

Fascinating watching various choices and desires sort out in threads like this one. I'm in the more gears are better camp too, far removed from the one gear camp. Maybe this comes with wanting to ride for exercise as well as fun, and use the motor for boost, not primary motion.

 

[AHicks]

Primary motion? The fact that the motor can be used for varying amounts of assist seems to be lost here.

 

[retiredNH]

Primary motion? The fact that the motor can be used for varying amounts of assist seems to be lost here.

Lost? What do you not get? That those that love throttles sometimes use them without pedaling? And that I'm not in that group? Or that I use the term "boost" as synonymous with "assist"?

 

[AHicks]

Lost? What do you not get? That those that love throttles sometimes use them without pedaling? And that I'm not in that group? Or that I use the term "boost" as synonymous with "assist"?

But we aren't talking throttle here are we? We're talking about utilizing the proper PAS level to get the job done. What part of this do YOU not get?

 

[retiredNH]

But we aren't talking throttle here are we? We're talking about utilizing the proper PAS level to get the job done. What part of this do YOU not get?

Geesh, all I did was make a general observation about a thread I found interesting. Sorry if I didn't stick closely to the direction YOU wanted to take things.
But I'm done arguing with you.

 

[tomjasz]

Twin sons of different mothers. Both grumpy fukes.

 

[AHicks]

Lost? What do you not get? That those that love throttles sometimes use them without pedaling? And that I'm not in that group? Or that I use the term "boost" as synonymous with "assist"?

Geesh, all I did was make a general observation about a thread I found interesting. Sorry if I didn't stick closely to the direction YOU wanted to take things.
But I'm done arguing with you.

General observation, right.....

Twin sons of different mothers. Both grumpy fukes.

Those living in glass houses.....

 

[tomjasz]

Those living in glass houses.....

I still have have a few merit badges available. PM an address and you can officially join the troop.

 

[Kayakguy]

Thats fine but don't make the mistake of designing a product with that bias unless you also recognize you are cutting out a significant swath of your potential customer base, and that customer base is not confused about what they want or why. You're the one with the narrower vision. Which again is fine if you are a single rider deciding how you personally feel like riding.

The classic finger-wagging line of "why don't you just buy a motorcycle' is best answered by saying 'show me a motorcycle you can pedal'. Without being able to make that response, you don't have a good answer to the question.

Gearing of the bicycle remains critical. Not for the motor but for the rider. Again... speed is irrelevant. As a rider I'm happiest at around 65 rpm. If I am going on flat ground I want 65 rpm. If go up a gentle incline, I want 65 rpm. If I am going up a steep hill, I want 65 rpm. My speed at these different points is incidental to achieving my preferred cadence. This is not my idea its the common practice, varied by personal preference. The number changes but not the practice of maintaining a set cadence. Give someone gearing they have to ride at 40 rpms if they prefer 70 and that bike is a failure in that circumstance regardless of what the motor thinks.

I Hate Ebike Torque-Sensing (maybe you should too)

Well, I don’t actually hate it, but it is a technology rooted in cycling’s past, whose existence was created to market a product to legacy riders.

talesontwowheels.com

I am in full agreement with your last paragraph. I have only taken one cadence reading (crank rpm) with my mid motor bike, which seems to be about 70 rpm (I need to take more readings to establish this). I do, almost instinctively, shift up or down to maintain this. It just feels very wrong to pedal at a lower rpm. Bike has a Nexus 7, which seems to provide the range of gearing that works well for me. My PAS cuts off at 20 mph, and I can get up to about 22 mph in 7th gear at my preferred cadence. I rarely use 1st gear, not even when launching. But if the descent is long and steep, I'm more likely to use the brakes than the motor. Partly that's because at age 84 I am somewhat wary of high speed crashing.

I also find that increasing effort, rather than changing gears, is another way to stay at my desired cadence. I surmise that this is the result of torque sensing. I can definitely tell that the motor increases output when I increase input. But maybe my analysis of this is wrong?

 

[m@Robertson]

I also find that increasing effort, rather than changing gears, is another way to stay at my desired cadence. I surmise that this is the result of torque sensing. I can definitely tell that the motor increases output when I increase input. But maybe my analysis of this is wrong?

Difficult to say. If we take the electric motor out of the picture, increasing effort when faced with an increasing grade (or headwind or similar); you could maintain cadence by increasing your pedal effort. No torque sensing because no torque sensor on an analog bike. Its your muscles and stamina maintaining that cadence.

If an electric motor is in the mix, a cadence-sensing bike could give the same result (it'll still be all about your muscles doing the work to match that cadence most likely) and a torque sensing bike could be providing some of the improvement... or not? A further confounding factor would be what kind of motor is in use. Hub or mid drive could yield different answers.

I certainly use increased effort to maintain cadence on a cadence sensing bike. When riding for exercise I will go thru segments where I want to work hard. When I decide I need a break I'll kick up the assist level and let my effort ease off while my cadence stays the same. So before... I was providing lets say 50% of the forward assist and after in the rest phase lets say I am providing 10%.

So... it depends. As the saying goes... your mileage may vary.