Help choosing kit - probablly Whoosh but will consider others...

[Bogmonster666]

Hi, Warning – long post…

Thinking of getting around to installing a kit on my old mountain bike. Tbh, still undecided on the best option. Don’t want to fork out too much money so looking at a kit and not a complete bike.
I am not enjoying driving much these days although I do have access to a car and can drive if needed. As well as not enjoying driving, petrol is expensive and cars are not very green (another reason for reusing my old bike).

I am 11 stone 0 lb and 5’10” although I plan to lose maybe another 7lb and have lost 6lb in the last month or so. I don’t commute into the office much as I usually work from home but if I do go in it’s a 21mile hilly ride each way. Using the Whoosh ‘Predictor’ calculator its about 270Wh each way at 15MPH. I can charge at work.
I have started to use my bike regularly for cycling to caving, relatively short distances but still some 10 degrees + hills and maybe 20kg of kit in panniers. Been doing this unassisted at the moment but a bit of a drag after digging and hauling 100 buckets of mud and rock from a cave…

Ideally, I would like to be able to some supermarket shopping as well. 12 mile round trip with short sections of 15 degree hill – Whoosh Pedictor calculated 177Wh round trip. Again, would expect additional 20KG and possible even a cargo trailer and a bit more weight…thinking I need one of the higher torque motors here….

Finally, I would ideally like to option of riding into Bristol when I go Bouldering – but this may be a stretch too far without an additional battery. This is about 42 miles round trip and about 600Wh on the ‘Predictor’ at 15Mph. In reality not sure I would do this and I think this requirement is quite an issue on a single battery as can’t recharge battery at half way point. I guess it depends how well the lower assist modes work and how much I can help…

I have not really cycled much at all for years and was never really much of a cyclist. I am quite fit although walking / caving fit, not cycling fit. I do have an exercise bike I occasionally use in the winter (and I think it is quite accurate in the info it gives). Had a little experiment last night in the baking heat and exercised for 1 hour at an output of between 250 to 300 watts continuously at a cadence of 90 to 95 RPM. I expect with a bit of practice I could manage 250 watts at 90 RPM for a couple of hours so I am certainly able to contribute to an electric bike’s effort – not wanting an effort free experience – but I do want to even out the hills.

I did an ebike conversion many years ago – it was a Bafang front hub motor but it was early days and not many DIY options about. It was throttle only and that sucked. Also, the rack mounted battery sucked as it was particularly high.

I have to say that I think I would be best off with a CD bike but not willing to pay for a pre-built. I know there are crank drive kits but worry about the reliability of these?
So have been looking mainly are rear hub so far and mainly Whoosh kits. There was no room to a cadence sensor on either side of my crank (not enough room on the left and on the right the front derailleur is mounted to the bottom bracket and the frame so minimal clearance from small chainring to derailleur bracket). I swapped the BB to get more room on the left but as expected is screwed up the chainline too much and the front derailleur could not pull the chain onto the big chainring. Sure, I could have gone to single chainring but I want an option if I have to pedal up hills under my own steam. The awkward derailleur bracked also limited options for replacement cranksets but I found a cheap double chainring. That fits and works and I have enough clearance for a left hand sensor how. It is only 22t and 36t so a bit small but on the 11t cog at 90RPM cadence I am doing ~22.5MPH and at a leisurely 60 RPM I am doing 15MPH so I think this just about works if not quite ideal.

I do have some questions on the Whoosh kits. How do the assist modes really work? Do they have different current limit cut-off or something different? Also, I think the older firmwares have no zero assist mode i.e. just human power with a powered up display showing speed – I think the newer firmwares on King Meter support this but is this what Whoosh ships?

As for the motor, I was tending towards the DWG22C-48V as this has higher torque at lower speeds (may be useful for the supermarket run). However, in downtube battery limited to 12 Ah so 576 Wh. Also, I wonder if this motor is as efficient as 15MPH as the other motors. Alternatively, the XF08 CST but this is 45NM instead of 60NM but has the option of a 17AH 36v battery at 612wh so I suspect a bit more range. I think my old bike had a front Bafang 36v hub motor and was maybe 50NM. I found this easily got me up most hills at full assist speed. I guess a front Bafang is still an option. I do wonder if I wasted my time changing the BB and fitting the double chainring – maybe I should have gone with the CD torque sensing TSDZ2 after all…but I do worry about the reliability of these and the availability of spare parts and ease of fixing. Another option is to switch from cassette to freewheel (my bike has a 7 speed cassette at the moment), and go with a SWX02 36v or more likely 48v variant?
Finally, I suspect I will need to file out the dropouts a bit – what width do I need between the flats for the various motors? I would also need to file the rear derailleur hanger I expect as this is the same width as the drop-outs. Ideally, I would rather not have to do this but I think it will be unavoidable.

I suspect Whoosh can best help me decide and I know they read these forums but also interested in other’s experience. The motor performance graphs on the whoosh site are useful but only for a few bike options. My gut feeling is the DWG22C-48V or change to freewheel and go with the SWX02 48v. Which of these motors is likely to better suit my needs and be most reliable?

Thanks for the help, C.

 

[Bogmonster666]

Trying to remember why I discounted the Whoosh BB torque kit after reading some good reviews. I see this on the Whoosh site: The TSDZ2 is not recommended for cargo bikes, please use our DWG22C kit for this. Not sure what the defintion of a cargo bike really is. Does an 11 stone rider with 20+KG of kit in panniers (probably not) or 11st + 30KG in a trailer (probably does constitute a cargo bike) ...

Also, whilst the 15.5MPH UK assisted restriction appears very slooow, not really sure I am in the market for de-restricting. I am sure with the right gearing and firmware the above kit will be able to assist well beyond 15.5 MPH but I am not interested in doing that because of the legal implications.

For kits like the DWG22C-48V or the SWX02 48v , if I am putting in say 300w of my own effort, what sort of speed would I attain on a 10 gegree and 15 degree hill with a rider at 11st?

 

[jimriley]

I do what you are aiming for with a bbs01b, 42t front cog, 13/34 X 7 rear block. Tow a trailer sometimes, often fully loaded panniers. I'm a stone or so heavier than you too.

 

[Nealh]

Too early for me to give much feed back about reliability of tsdz2, my one is fitted to a kona ute longtail cargo bike and is used for toing a trailer as well with 2 x 9 gearing .
On ES forum someone has 30k miles so they say on a tsdz2 with no issues.

 

[sjpt]

We've got a 4 year old XF07 from Woosh on the front of our tandem. We knew (and Woosh explicitly warned us) it was low powered when we bought it but there was no good legal 700c alternative at the time. It really helps on hills , but more help would be even better! I'd certainly go for something like a DWG22C-48v if I had to change it now. (I see it's showing as not available in either battery size on the Woosh site at the moment, but that site is not always up to date.) It sounds as if you are outputting as much power as I suspect my wife and I can manage between us.

The control system isn't perfect but does fine for our not very demanding riding. I think that it provides a different current on each level, up to a different cutoff speed on each level, (graphs in post below https://www.pedelecs.co.uk/forum/threads/help-choosing-kit-probablly-whoosh-but-will-consider-others.43846/#post-657958) I'm sure Woosh can clarify. About 1/2 pedal turn before motor kicks in. I wouldn't want to be without the brake sensors, mainly because it prevents the risk of the motor engaging in the middle of a slow manoeuvre.

I don't know how much difference there is between the DWG22C and DGWX but this may be relevant.

Motor Simulator - Tools

Our ebike motor simulator allows you to easily simulate the different performance characteristics of different ebike setups - with a wide selection of hub motors modeled, and the ability to add custom batteries and controllers and set a wide variety of vehicle parameters you'll be able to see...

ebikes.ca

That shows good efficiency at 15mph and optimal efficiency much higher up.

For us on the XF07 the issue is the rapid drop-off of efficiency below 10mph

 

[Woosh]

Trying to remember why I discounted the Whoosh BB torque kit after reading some good reviews. I see this on the Whoosh site: The TSDZ2 is not recommended for cargo bikes, please use our DWG22C kit for this. Not sure what the defintion of a cargo bike really is. Does an 11 stone rider with 20+KG of kit in panniers (probably not) or 11st + 30KG in a trailer (probably does constitute a cargo bike) ...

cargo bikes: when the rider + bike + load exceeds 150kgs

The issue is motors with torque sensors like the TSDZ2 delivers x times your pedaling power. x can be selected between 1 and 5. With a heavy load, you need more power from the motor for your pedalling. That is much better delivered by a kit with cadence sensor (BBS01, DWG22C, SWX02, BPM kits) than a kit with torque sensor. Kits with cadence sensor can deliver maximum torque with the throttle.
The maximum power is limited by the kit's controller.
Our TSDZ2 has a 48V 10A controller, the DWG22C has 48V 17A controller.

The DWG22C is just as powerful as the Bafang BPM powered Woosh Big Bear (36V 20A controller) in this picture, pulling more than 100kgs:

 

[Jodel]

I can't answer all of your questions, but I have installed two of the Woosh DWG22-C kits. One is on our tandem, the other on a solo. Both have the downtube 12 Ah battery. You can read about my experience of fitting the kit to the tandem in one of my posts on the site. I'm a similar size / weight to you and the DWG22 has more than enough grunt to get me up any hill I've encountered. It does a good job on our tandem too, so should easily accommodate your wish to pull a trailer if required.

I tend to use assist Level 2 most of the time as this gives a good balance of range / power / speed. The Woosh set-up is configured to provide assistance up to a given speed and adds / reduces power as required. As a rough and ready guide, I've found that speeds on the tandem are approximately:
Level 1: 8.5 mph
Level 2: 11.5 mph
Level 3: 14.00 mph
Level 4: 15.00 mph
Level 5: 15.5 mph

The tandem is about 160kg all up weight and we can manage a fairly safe range of 50 miles at Level 2. A lot of the time we're pedaling above the 11.5 mph assistance level, so not using too much from the battery. Most of our trips tend to be around 30 miles and even with Edinburgh's hills / headwinds there is loads of power available with little voltage drop other than on the very steepest hills. Even if I go up to Level 3, there is still plenty of energy to cover at least 30 miles. Speeds are slightly higher on the solo as there is far less weight and energy consumption is less too as it is much lighter than the tandem.

Woosh are helpful in offering advice if you send them photos of your bike. They have a deservedly good reputation on here and I've had no issues with my kits.

On both my installations, I only used a single torque washer* on the cassette side of the hub to move it over to the driveside and keep the chainline as close as possible to the original. That also let me reduce the dish of the wheel a bit. I had to use a few spacers to get the disk aligned correctly on the tandem (it has a 145mm OLN dimension rather than the more usual 135mm of MTB's). If you have issues with front derailleur alignment, it is usually possible to fit an eccentric 'shim' to the seat tube to allow more adjustment on the derailleur throw. SJS or Spa cycle often stock these sort of odds and ends.

There is nothing particularly difficult in setting up one of the Woosh kits for anyone with a modicum of spanner twiddling skill.

I only had to file the dropouts to remove some paint, the 10mm flats of the 12mm hub motor axle then slotted in quite easily.

*It may not be strictly neccessary, but I used torque links on both of my installations. Both my bikes have alloy frames and I wasn't keen on using the supplied torque washers on their own with only alloy dropouts. I think 'Endless Sphere' tested the amount of force required to spin an axle and found that you need 60Nm to do this. That measurement was for each end of the axle, so in reality you'd need more than 120Nm before you have any issues. I just prefer the belt and braces approach of additional torque links.

 

[sjpt]

The control system isn't perfect but does fine for our not very demanding riding. I think that it provides a different current on each level, up to a different cutoff speed on each level, I'm sure Woosh can clarify.

This graph is NOT for the Woosh Lishui controller (apart from anything else that has 5 levels), but does show the sort of way I think the Lishui behaves.

 

[Woosh]

This graph is NOT for the Woosh Lishui controller (apart from anything else that has 5 levels), but does show the sort of way I think the Lishui behaves.

View attachment 48111

the Lishui controllers have a similar behaviour.

 

[sjpt]

We usually ride at level 2/5 on the XF07 tandem, typically at around 10-12 mph (so using assist and battery), range probably a bit under 30mph on 13ah battery, Winchester, not flat but only a few steepish hills. We use level 3 for slight uphill busy roads and ride nearer 15mph to get them over with quicker. The only times I have to think about the controller setting is to wind it up to 4 or 5 before some steep hills, that helps keep speed (and therefore motor efficiency) up. Once the speed drops it is too late to increase assist; at low speed the extra assist current seems to go into lower efficiency rather than more power out.

 

[Waspy]

Having very recently installed an XF08C rear wheel hub kit from Woosh, I may be able to answer a couple of your questions.

First of all I weigh 15kg more than you. I have no trouble at all getting up hills with his kit.

I replaced my triple front chainrings with a single 38 tooth chainring and dumped the front derailleur. Something I don't regret at all, I only ever use the top four gears now (on an 8 speed cassette) since I fitted this kit.

Fitting the left side PAS is an absolute doddle, Woosh say that you should have metal bearing cups on your BB rather than plastic as some have.

I do have some questions on the Whoosh kits. How do the assist modes really work? Do they have different current limit cut-off or something different? Also, I think the older firmwares have no zero assist mode i.e. just human power with a powered up display showing speed – I think the newer firmwares on King Meter support this but is this what Whoosh ships?

I'm not sure how the assist modes work. There appears to be no cut-off, just different levels of power supplied to the hub according to the level selected.

My King Meter KM529 (which Woosh ships... to me anyway) does not have a zero assist mode, if it's turned on then you have at least assist level 1 selected.

Finally, I suspect I will need to file out the dropouts a bit – what width do I need between the flats for the various motors? I would also need to file the rear derailleur hanger I expect as this is the same width as the drop-outs. Ideally, I would rather not have to do this but I think it will be unavoidable.

You need about 10.25mm drop-out width. For my XF08 axle anyway.

My bike has 138mm between the drop-outs.

Here's how I fitted my rear wheel: With the bike upside down, I removed the chain and (mechanical) brake caliper completely (you really don't need to do this). Next I offered up the wheel to the drop-outs, I could get it in and out OK but for an easier fit I took a file to the drop-outs and hangar, but only removed a tiny bit of metal, just to make wheel fitting and removal easier (I could have gotten away without doing this also).

Next I added the washers. There are two thick, plain washers and two anti-rotation washers. I placed the two plain washers inside the drop-outs and the two ant-rotation washers outside the drop outs, I had to pull the frame apart a few millimetres to achieve this.

Once I had that sorted, I took the wheel off, removed the spacer behind the disk rotor bolts and bolted the rotor onto the motor. Then I fitted the wheel, fixed the chain on (using a quick-link or whatever it's called), refitted the caliper and used the Park Tool video on Youtube to set it up properly.

I hope this may be of some help.

 

[Bogmonster666]

WOW - loads of detailed answers really quickly - what a helpful forum

The graph appears to show (accepting it is not from the Lishui controller) that the assitance drops off in the lower modes at lower speed thresholds and also offers less power when below the point where the assitance cuts off. So effectively a combination of current limit and speed limit with a gradual ramp down in assiatance at a set level - I think this makes sense. In the example in the graph, low starts to ramp down assitance at 15khm and has about 40% assitance below 15kph. I am sure the Lishu numbers are different (especially as they have 5 modes) but I think this is a reasonable approach. It also ties in with Jodel said about their experience (mode 2 is 11.5 on the tandem and a bit faster on the solo.

I beleive the 48v batteries are due in at the end of this month for the DWG22C - not in a massive hurry so not a problem.

 

[Jodel]

Bogmonster666 - Keep us posted as to your progress, it's always interesting to hear of / learn from the experiences of others.

 

[eFred]

Fitted the Shengyi DWG22C kit from Woosh bikes a couple of years ago and it has been faultless. Did another bike shortly after with the same kit and no problems with that either. Went for the option without the brake switches or throttle.Less wires and I prefer things to be as simple as I can make them!

 

[oldie1982]

I have the 48v SWX02 Woosh kit (2 years old). Plug and play, only done 300ish miles but its been perfect with no issues. Everything plugs in and works as it should. The controller is built into the battery so its a very neat installation. I cant really tell you much about the range as i pedal a lot and even after 20 miles i only used one bar of the battery. I did weight 110kg back then.

More recently i put together a custom kit, i like tinkering. The biggest difference is finding a location for the controller and sorting out the wring yourself.

 

[Jodel]

Once the speed drops it is too late to increase assist; at low speed the extra assist current seems to go into lower efficiency rather than more power out.

sjpt, that's interesting to note as the 48 volt DWG22 has not exhibited that characteristic in our use. On steep hills we usually climb at about 8 - 9 mph in level 2 and if you then select level 3 or above, there is a noticeable surge from the motor and we continue the climb at around 12 - 13 mph.

The only times I've noticed a lack of thrust on the tandem is starting off from rest on really steep hills - it takes a little bit of speed (5 mph?) before the motor chimes in and starts to make its contribution felt. That said, on those kind of hills, we wouldn't even attempt a hill-start without the motor to help us.

 

[Bogmonster666]

sjpt, that's interesting to note as the 48 volt DWG22 has not exhibited that characteristic in our use. On steep hills we usually climb at about 8 - 9 mph in level 2 and if you then select level 3 or above, there is a noticeable surge from the motor and we continue the climb at around 12 - 13 mph.

The only times I've noticed a lack of thrust on the tandem is starting off from rest on really steep hills - it takes a little bit of speed (5 mph?) before the motor chimes in and starts to make its contribution felt. That said, on those kind of hills, we wouldn't even attempt a hill-start without the motor to help us.

I am guessing this is the difference in torque between these different motors. The DWG22 is supposed to have a lot more lower speed torque. I also looked at the simulator that was linked earlier in this thread and once you understand how to use it, it's very interesting. It certainly shows that motors at full throttle are very inefficient at slower speeds (bogged down on a steep hill and not enough torque to accelerate) which is why changing mode early is probably more important on the lower torque motors so as to not bog down in the 1st place. Looking at the simulator, the DGWX (yes, I know not exactly the same motor) is close to max efficiency at 9mph on 40% throttle (would be interested to know if the 5 controller modes are 20%, 40%, 60%, 80%, 100% with taper down in assistance after threshold speed). At 80% throttle it's at maximum efficiency at 18mph although assistance (power) starts to drop off rapidly at 15mph. Based on the DGWX and the simulator, with moderate rider input a 15% incline on 40% should be quite doable and that ties in with Jodel's comments. Tbh, I expect the DWG22 maybe overkill for my needs if it is anything like the DGWX. Also, looking at the simulator, and seeing a Tongxin motor, I think that is what I used last time...the motor listed in the simulator looks poorly suited at full throttle limited to 15mph in the UK, on the flat it does not reach full efficiency until about 27mph...if this was indeed the motor I had it may explain why it wasn't ideal and appeared heavy on the battery...last time around there was limited info out there and I also only had throttle without assistance modes so tended to be all or nothing as holding the throttle at 50% wasn't easy.

 

[Bogmonster666]

I must admit that I am starting to have cold feet on the DWG22. I keep flipping between that and theTSDZ2...

I think the TSDZ2 will be easy to fit to my bike (although I may need a spacer on the BB where the front derailleur bracket meets the BB - may work without as kit works on 68mm BBs as well).

I was worried about the reliability of the TSDZ2 kit and the weight I carry on my bike but in reality I am probably well within its capability and in reality a trailer may never happen anyway. I suspect I would travel faster on the TSDZ2 for for longer distances as presumably the motor keeps assisting up to max set speed based on a multiplyer of my input, even on lower assist modes? Have I got this correct? E.g. tour mode will keep assisting upto 15.5mph?

The hub motors only assist up to a lower speed on lower assist modes e.g. on mode 2/5 the assistance may drop of rapidly about 11mph?

I have already changed the BB and crankset in anticipation for a rear hub kit but not spent much so if I change direction it is still not too late...

I also think a round trip to Bristol and back is achievable on be the TSDZ2 but maybe not a hub.

Does anybody have an idea of my the assist levels on the TSDZ2 e.g tour puts in 75% to riders 100% etc?

Ideally I would try a couple of different options but not too much choice around here...

 

[Woosh]

I suspect I would travel faster on the TSDZ2 for for longer distances as presumably the motor keeps assisting up to max set speed based on a multiplyer of my input, even on lower assist modes? Have I got this correct? E.g. tour mode will keep assisting upto 15.5mph?

yes.
I usually avoid making remarks on personal preferences for one kit among others because although we try to maximise their advantages and minimise their disadvantages, they all have pluses and minuses. If it's your first conversion, my recommendation is not to concentrate too much on the technical details because your perception may change completely when you use the actual kit.
There are some fundamental differences between torque control and speed control, crank motors and hub motors but by and large, people just get round to change their riding habit a little bit to make the most of their kit.
The main thing is, if you are very good with gears, then you would likely to like crank drives more.
If I remember correctly, the reason you were looking at the DWG22C is because you want to pull a trailer. I recommend this motor because it's rock solid for the job. That advice has not changed but you seem to worry about assist speed on the hub drive. That is not a big problem for most people, they just press the + button and increase the assist level when they need to go faster or they are tired. Controllers are programmed for the many, not the few.

 

[pedalfettal]

Battery capacity options:
- One mahoosive battery to carry you the furthest.
- - a lot of unused weight on shorter journeys
- - single point-of-failure

- Two same capacity batteries.
- - good for ocd 'must match' purpose
- - one might be too little for typical journey necessitating always carrying both

- One larger and one smaller battery.
- - can defer purchase of smaller/larger until experience gained
- - most configurable option

I favour the tsdz2b with the newest freewheel clutch (nb. Brand new just out - maybe wait for reviews before purchasing). This might allow you to 'sip' the battery and only engage electric assistance when necessary.