Is the 350 enough?

emco5

Active Member
Finding a 350 watt e-RAD/BaFang-equipped bike to test ride has not happened, so I’m hoping to get some first-hand feedback here. Most of my commute needs no power assist, but there are a couple very steep climbs that make the trip miserable. I’m 170# and ride a MTB with 26” wheels and 32t granny gear. Going fast is not a requirement, I just want to be able to climb hills without needing a shower at the top. I’ve no doubts that the bulkier 750 and 500 watt systems would do the job, but I would prefer the lighter 36v 350 system if it is sufficient. With the 32t granny, do you think the 350 is strong enough in PAS mode for serious hills without being over-loaded and getting hot?

Also, because I only need power assist for hills there is no need to turn on the system, otherwise. Is there noticeable crank drag when the battery is off?
 

pocomo

Member
I do not experience any noticeable crank drag when the system is powered down, but you can certainly feel the additional weight.

I can't really say if 350W would be enough. I know a 350W Stromer I test rode (rear direct-drive hub, so different technology) felt a little underpowered on some tough hills around here; I was still somewhat out of breath at the top. I keep my Lectric 750 'leashed' under 500W draw and it's perfect for me for street riding, but I can honestly say I am not tempted to turn it off completely - the bike is not really that fun to pedal unassisted with the extra weight.

I bought mine for likely the same reason as you - commuting to work without being drenched in sweat upon arriving, and it performs this task admirably.
 

one4torque

Active Member
I've got a 350 watt Sonders fat-tire bike and I can cruise with pedal assist @ 19.5mph over hills and into wind.
It provides a good work out.
If you want to ride it like a motorcylcle... then you will not be happy with 350 watts.

Clarification to my hill climbing statement...... you "can" go 19.5 mph up an overpass, but you will be providing ample pedal assist. It won't be casual PA.

Same goes for running into a head wind.... I'm working to maintain 19.5 peak mph into a head-wind.

But I'm riding to get a work out.

Also I'm a 47 yr old middle age guy with a bum knee for what it's worth, so I'm no olypmic athelete :)

If you want to do pikes peak, then you will want something more.

Hope that helps.
 
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emco5

Active Member
pocomo:
> I do not experience any noticeable crank drag when the system is powered down...
> ...I can't really say if 350W would be enough. I know a 350W Stromer...felt a little
> underpowered on some tough hills

Much appreciate the crank drag info, that is important for my application. My only experience with a hub motor was with a geared 250 watt unit. It was horribly anemic and of no value at all on my hills. The same power through a derailleur system or Nexus hub would make a lot more sense--engineering 101.


one4torque:
> I've got a 350 watt Sonders fat-tire bike and I can cruise with
> pedal assist @ 19.5mph over hills and into wind.

If the 350 can move a Sonders at 19.5mph, I'm thinking it will have enough energy to move my MTB with 26 x 1.5 Pasela's on pavement.

Thanks for the feedback, gentlemen.
 

Adrian

Active Member
pocomo:
> I do not experience any noticeable crank drag when the system is powered down...
> ...I can't really say if 350W would be enough. I know a 350W Stromer...felt a little
> underpowered on some tough hills

Much appreciate the crank drag info, that is important for my application. My only experience with a hub motor was with a geared 250 watt unit. It was horribly anemic and of no value at all on my hills. The same power through a derailleur system or Nexus hub would make a lot more sense--engineering 101.


one4torque:
> I've got a 350 watt Sonders fat-tire bike and I can cruise with
> pedal assist @ 19.5mph over hills and into wind.

If the 350 can move a Sonders at 19.5mph, I'm thinking it will have enough energy to move my MTB with 26 x 1.5 Pasela's on pavement.

Thanks for the feedback, gentlemen.
There's one thing doing 19mph on the flat and another thing entirely to get up a hill. ;)

Go for the 500W - the weight difference between it and the 350W is negligible - if you're planning on mainly using it to go uphill and you will turn off PAS the rest of the time (or put it in lowest PAS to make up the difference in motor weight) you'd probably save more weight by getting a smaller battery.

If you have really steep hills, you can always switch out the front chainring for a smaller one - like the Lekkie 42T or get an adapter and put on any 3rd party chainring.

Edit; I just checked the weights listed for their latest revisions here; http://www.szbaf.com/en/components/motor.html and there's 500g (1lb) difference between the motors. Really, if you want this for tackling hills, you want more power not less. the difference in torque is 20Nm (100 as opposed to 80).

BTW, there is drag with the motor off as far as I can tell but not a lot. Certainly, the lowest assist level will offset the added weight and any extra drag.
 
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sal

Member
Emco5, I agree with everyone input so far. I also agree no noticeable crank drag, but u definitely want PAS level in gaged, the weight of battery and motor will factor in up hill and flat street riding. I use the bbs02 48 v. Battery, 750 bafang motor. 500W is 4.3 kg vrs. 4.8 kg my 750watt, minimal weight increase. The bigger the better for ur steep hills, 350 is under powered, must get mid-drive motor. Also 32t chainring is a hill climbing beast. But, U might consider changing chainring to the right type of motor u get, 2:1 ratio fine, in order to keep motor running cool and efficient. Good luck in your decision.
 

Mike Smith

Active Member
There's one thing doing 19mph on the flat and another thing entirely to get up a hill. ;)

Go for the 500W - the weight difference between it and the 350W is negligible - if you're planning on mainly using it to go uphill and you will turn off PAS the rest of the time (or put it in lowest PAS to make up the difference in motor weight) you'd probably save more weight by getting a smaller battery.

If you have really steep hills, you can always switch out the front chainring for a smaller one - like the Lekkie 42T or get an adapter and put on any 3rd party chainring.

Edit; I just checked the weights listed for their latest revisions here; http://www.szbaf.com/en/components/motor.html and there's 500g (1lb) difference between the motors. Really, if you want this for tackling hills, you want more power not less. the difference in torque is 20Nm (100 as opposed to 80).

BTW, there is drag with the motor off as far as I can tell but not a lot. Certainly, the lowest assist level will offset the added weight and any extra drag.
 

Mike Smith

Active Member
Agree. Go with the 500 W and you won't be sorry. More power equals extra power and speed up hills. There is a huge difference between 350 and 500 w in my opinion, as I have 500 w at 260 plus pounds and my wife has 350w at 140 pounds and there is no way she can keep up with me in a race. Go for the larger power motor, imho.