Need a beefier drive than TSDZ2; keep existing 48V batt for BBSHD or upgrade to 52V?

[Peddlin' Pedro]

Love the ride experience of the TSDZ2 - if not the well known design & manufacturing issues - but it's become clear it isn't up to what I need with carrying and towing heavy loads on steep terrain. Consensus of some extremely helpful and experienced modders is that even with firmware updates and internal cooling mods it's unlikely I could squeeze enough extra torque out of it at higher cadences and would still likely end up frying it or, if I'm lucky, at least needing to strip it more often than is practical.

So, while I've still got a decent condition and un-abused drive to sell on, the strongest contender for a beefier and reliable replacement seems to be the BBSHD.

Question is: should I order the 48V unit and stick with my existing 48V 17.5Ah LG-celled HL pack (from PSW Power), or go all-in and order the 52V BBSHD and an appropriate 52V pack, probably 21Ah?

Would appreciate thoughts from those running 48 and/or 52V BBSHDs, and recommendations for known good quality off-the-shelf packs of a suitable spec, or UK builders of same.

The bike is very much a workhorse and in daily use for both domestic and work duties, so (relative) reliability is essential.

Cheers!

 

[vfr400]

For a bike like that, I'd fit a 201 rpm Bafang BPM hub-motor. It'll give a much more pleasant ride.

Bafang BPM2 48V500W Rear Driving E-Bike Motor Wheel RPM 201

Bafang BPM 48V500W Rear Driving Hub Motor E-Bike Wheel. You can select S09P, S12P or S12S controller for this motor.

bmsbattery.com

S12S controller and LCD3 to go with it.

 

[Peddlin' Pedro]

For a bike like that, I'd fit a 201 rpm Bafang BPM hub-motor. It'll give a much more pleasant ride.

Bafang BPM2 48V500W Rear Driving E-Bike Motor Wheel RPM 201

Bafang BPM 48V500W Rear Driving Hub Motor E-Bike Wheel. You can select S09P, S12P or S12S controller for this motor.

bmsbattery.com

S12S controller and LCD3 to go with it.

Thanks, but needs to be mid-drive for a number of reasons.

 

[vfr400]

Thanks, but needs to be mid-drive for a number of reasons.

Which are????

 

[Peddlin' Pedro]

Which are????

Weight distribution and subsequent handling while climbing, durability, serviceability, daily use with 250kg+ on steep terrain, availability of rim I'd need to lace hub into (none available for at least three months) and ease & speed of conversion on a bike that can't be out of service for longer than absolutely necessary. None of which was leading me towards a hub-drive.

That said, I try not to discount anything out of hand so I'd consider a rear hub drive if the above considerations could be addressed convincingly and the result was sufficiently reliable.

 

[vfr400]

Let's take them one at a time:
Weight distribution. What's the problem? It should be perfect with a rear motor!
Daily use on steep terrain. Again this motor is perfect for that. How do you see a problem?
Availability of rims. The one I showed you comes with a rim, which you can't see when on your bike. Why do you think you need something special?
Speed of conversion. It normallt takes me about an hour to fit a motor wheel. The rest is just a bit of wiring. Maybe 2 hrs max for the whole job.
Handling while climbing would be better than a mid drive due to more suitable weight distribution
Durability would be infinitely better than any mid drive.
Serviceability. What is there to service. These motors are tested to 30,000 miles. No mid drive can match that. Then there's the wear you get on the drive train with a mid drive, which would be substantially reduced.

To summarise, a BPM motor is stronger, more reliable, more durable, cheaper, more powerful, has lower running costs, needs less maintenance and easier to get on with than a BBS**.

 

[Peddlin' Pedro]

Let's take them one at a time:
Weight distribution. What's the problem? It should be perfect with a rear motor!
Daily use on steep terrain. Again this motor is perfect for that. How do you see a problem?
Availability of rims. The one I showed you comes with a rim, which you can't see when on your bike. Why do you think you need something special?
Speed of conversion. It normallt takes me about an hour to fit a motor wheel. The rest is just a bit of wiring. Maybe 2 hrs max for the whole job.
Handling while climbing would be better than a mid drive due to more suitable weight distribution
Durability would be infinitely better than any mid drive.
Serviceability. What is there to service. These motors are tested to 30,000 miles. No mid drive can match that. Then there's the wear you get on the drive train with a mid drive, which would be substantially reduced.

To summarise, a BPM motor is stronger, more reliable, more durable, cheaper, more powerful, has lower running costs, needs less maintenance and easier to get on with than a BBS**.

The hub-drives I've ridden felt better suited to constant (ish) speeds, but my experience of them is limited to servicing the bikes they're built onto and re-truing/rebuilding the factory wheels they're built into when the local road surfaces break them. I'll admit that none have needed any work on the drive or controllers so I've not paid much attention to what they were, beyond that they've all been on light-duty hybrids/commuters. My experience of bikes in general though is good, including wheel building/selection so don't need help with that, but thanks all the same.

I'm towing 75kg+ with a gross weight frequently in excess of 250kg on very steep hills, so weight forward and low down is helpful for tracking so long as it doesn't compromise rear wheel traction, which is unlikely given the weight already over the rear axle.

As above, it's a long tail cargo bike with a lot of weight over the rear axle, ridden on genuinely appalling road surfaces shared with narcissists in their four-wheeled personality substitutes, and again, towing a heavy trailer. This means I frequently have to choose what to feed to the potholes; usually the larger diameter bike wheel. That's why I run strong, eyeleted, wide section rims: for durability and to get the most volume I can out of 2.4" tyres.

Like I said, I've not found sufficiently comparable use-cases that suggested a rear hub-drive was the solution but would be genuinely interested to hear of some. Do you have first hand experience of same?

 

[vfr400]

The BPM is a brute of a motor compared to your average 250w hub-motor. A typical Chinese 250w one runs at 36v and 15 amps, That BPM runs at 48v with 30 amps which is nearly 3 times the power. The other important thing is that most standard Chinese ebikes have 260 rpm motors. That BPM is 201 rpm, so it has much better efficiency at low speed.

 

[peter.c]

Currently running hd at 52 v with 19.2 ah battery the power is endless the torque is over the top you can turn the power down [it will out perform the tsdz2 on level 2or 3]
But could not recommend it for your needs, chain life under your load will very short can kill/snap a cheap chain if you abuse it
The 48v version hd which was fitted in a fat bike and paired with the same battery as yours , had a more subtle power delivery but the battery life was way short when compared to a tsdz2 , but that still will not help with the chain drive train loading especially at the additional length you require

 

[Peddlin' Pedro]

Currently running hd at 52 v with 19.2 ah battery the power is endless the torque is over the top you can turn the power down [it will out perform the tsdz2 on level 2or 3]
But could not recommend it for your needs, chain life under your load will very short can kill/snap a cheap chain if you abuse it
The 48v version hd which was fitted in a fat bike and paired with the same battery as yours , had a more subtle power delivery but the battery life was way short when compared to a tsdz2 , but that still will not help with the chain drive train loading especially at the additional length you require

That's helpful, thanks. Was planning to dial it back a lot as don't need or want high speeds, masses of torque or wrecked drivetrains, just more oomph than the TSDZ2 can deliver at higher cadence without cooking. Smooth power application is also important when towing big loads so was fully expecting to tinker with the standard settings.

Running 42F:40R as my lowest climbing gear, which is a bit too slow for stability when fully loaded on a steep gradient. Would be nice if I could push 42:38 or 36 to keep things straighter.

Still on my first chain - obviously with the lower output of the TSDZ2 - but I do maintain the bike carefully and turn the motor right down or off when on the flat or downhill. Also got a Hope Pro 4 with steel freehub body on the back for durability.

So from a range and efficiency perspective, sounds like a toned down 52V would be the better option? Still not ruled out the BPM option but it would be more of a faff sourcing parts with, drivetrain components like chainsets, BBs are thin on the ground.

 

[peter.c]

The motor is the same just more watts at 52v fully charged 58v the other point of note is the increase in weight and bulk the hd is a heavy but durable
The battery was sold as Panasonic tessla cells that just meant 21700 type cells in the real world
unless you need 1500-1700 watts peak stick at 48v and get higher capacity [ ps the battery case is huge ]