Yose Power 350w rear drive - Kit review and stuttering fault

GaryMc

Finding my (electric) wheels
Dec 25, 2018
11
2
Hello, I am new to ebikes and this forum. I have just installed the 350w Yose power rear hub motor kit, with 13.5ah hailong battery.

First discovery - no controller! After a while, I realised that it was built into the battery base plate. Yose Power really ought to update the instructions and stop including the superfluous separate controller bag in the box.
Otherwise, first impressions were good.

Niggles I encountered when fitting were, firstly, the heads of my 5mm water cage allen bolts were too deep for the slots in the battery mounting plate. Maybe I could have found other screws but I just ground the allen bolts down instead. I also had to use Riv-Nuts to make a few new 5mm cage mounts further up the down tube. Otherwise the battery fouled on the seat post tube. No big deal, but all new to me and a wee bit of a fiddle.

The PAS sensor wouldn't fit as my bottom bracket was an old item with weird plastic retaining rings (without the required 20 splines). So I had to install a new bottom bracket. Having read that there is sometimes not enough room for the sensor, I bought a 127mm length item. Wrong! Too big. So on went a standard 122.5mm and the sensor then fitted ok.

I did appreciate the tools that YosePower supplied. I actually needed a new set of allen keys, so that was handy. Likewise, the crank puller did the job.

The electrical connections seem to be of good quality and well thought out, at least they are a snug fit and look like they would be weatherproof.

The whole build took quite a few evenings as I also replaced the crankset, chain, installed new shifters, brake pads, mudguards and dynamo lighting. The bike itself was a late 90's rigid MTB, made by the Edinburgh Bicycle Coop. It was in fairly sound condition but needed some upgrading.

Today I had my first 20 mile ride. Impressions? Pretty good. It's quite amazing to plough up hills in top gear with only moderate pedalling and maintain a decent speed on the flat too. I used PAS level 5 all the way and managed to shave 15 mins off my commute time. However, I seem to have a problem with the PAS. When pedalling, especially when trying to accelerate quickly, the power seems to cut out for a few seconds. This is quite annoying at lights, for example. It can be overcome by using the throttle and then going back to PAS but even then, it sometimes stutters. I've looked on Pedelecs and Google and it seems that the sensor or wiring could be worth checking out. On my bike everything is new and nothing has seen the rain - so no question of corrosion or a duff battery. I'll try taking the plugs apart and rejoining them first. Failing that another sensor, in case I damaged it on installation ...

As for speed, using the PAS only and pedalling has the bike cruising at about 18mph (with the aforementioned stuttering). Whacking on the throttle and pedalling sees the speed go up to 20ish. The PAS does seem to hold the bike back a bit at the top end, although it is still a boon on the hills.

I'm quite keen to sort the PAS problem out as I don't want the hassle of holding the throttle open all the time, never mind the juice that it pulls when riding this way!

Most often I ride in top gear (occasionally 2nd or 3rd from top), pedalling moderately, pulling 200-250 watts at about 18mph and am untroubled by hills. So it's a worthwhile kit, despite a few niggles.

Gary
 

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egroover

Esteemed Pedelecer
Aug 12, 2016
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I have the same kit, and was too puzzled by the missing controller until I realised it was built in. I too had to change the bottom bracket to a 122.5mm one for my 1999 GT MTB to fit the supplied PAS sensor. That bit was a right faff getting it to fit.
It sounds like it could be the sensor is slipping in the bottom bracket ? (especially when accelerating) Is it a firm fit over the bottom bracket spindle ? Does it rotate freely in the hand ?The sensor shell has teeth on the outside facing inwards which 'slot' into the BB shell, which stops that bit rotating. I was going to swap out the supplied sensor with another I bought which was slimline (so I could revert back to the original BB width), haven't got around to it yet and the yose one is working fine. There is a slight delay with mine when starting before the motor kicks in, maybe 1/3 of a pedal roratation (will have to check), I think there is a setting in the LCD for the number of magnets (on the sensor) which you might be able to tweak. Good luck in finding the fault
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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GaryMc

Finding my (electric) wheels
Dec 25, 2018
11
2
I have the same kit, and was too puzzled by the missing controller until I realised it was built in. I too had to change the bottom bracket to a 122.5mm one for my 1999 GT MTB to fit the supplied PAS sensor. That bit was a right faff getting it to fit.
It sounds like it could be the sensor is slipping in the bottom bracket ? (especially when accelerating) Is it a firm fit over the bottom bracket spindle ? Does it rotate freely in the hand ?The sensor shell has teeth on the outside facing inwards which 'slot' into the BB shell, which stops that bit rotating. I was going to swap out the supplied sensor with another I bought which was slimline (so I could revert back to the original BB width), haven't got around to it yet and the yose one is working fine. There is a slight delay with mine when starting before the motor kicks in, maybe 1/3 of a pedal roratation (will have to check), I think there is a setting in the LCD for the number of magnets (on the sensor) which you might be able to tweak. Good luck in finding the fault
Hi - thanks for your quick feedback! Yes, fitting the bottom bracket was a faff. I ended up bodging on a £10 Halfords bottom bracket with a (slightly mangled) Shimano alloy retaining ring. The steel ring with the Halfords part looked much better, but didn't fit very well and allowed me to damage the bike's threads...

Anyway, the new bottom bracket is a fitted and secure. The outer sensor teeth are snugly fitted into the bottom bracket. The inner sensor seem to be a good fit on the square taper. I'd be surprised if they are slipping. The inner part of the sensor turns fairly freely.

With the initial longer bottom bracket the sensor rode up over the square taper and the inner teeth were really squashed - so much so that it was hard to rotate the axle. I realised then that something was wrong and reverted to the (correct) 122.5mm bottom bracket. But I wonder if something has been damaged inside the sensor?

I'll try and find the problem and post here if I do resolve it.
 

GaryMc

Finding my (electric) wheels
Dec 25, 2018
11
2
My PAS works perfectly.
Check PAS sensor gap to disc should be 1mm or 2mm at most.
Also list your P & C settings as these can be fine tuned to adjust PAS niggles, many have since joined the Yose club after I reported on getting one a little over a year ago.

https://www.pedelecs.co.uk/forum/threads/yosepower-hub-kits.30061/
I don't think there is any gap to adjust with the KT-V12L PAS sensor. It's an integrated unit.

Adjusting the settings might be worth a bash though. Thanks for the tip!
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Ah yes forgot they come with the V12L which I didn't use nor the controller with my Yose as I married my hub with 48v controller and a DL sensor & 12 pole disc modded to fit over a Hollowtech BB.
P1 87
C1 try 05 - 07
C3 try 0 or 8
C14 try 3 if set to 2.
 

GaryMc

Finding my (electric) wheels
Dec 25, 2018
11
2
The problem appears to be solved. First I checked the sensor connector - seemed fine (3 straight, shiny pins). Secondly, off came the sensor itself. When I turned the inner ring, the power came on within 1/4 - 1/2 turn. So far so good. Next I gave the axle a wipe in case any Copaslip had found it's way there. When I put the sensor back on I noticed that the inner ring was at the limit where the square taper blends into the circular section of the axle. To try to avoid slip, I put a few turns of PTFE tape on the axle and the inner ring of the sensor on top of this. Seemed like a snug fit and the axle still moved freely. I used a large diameter socket as a drift to gently tap the outer ring into the bottom bracket splines.

Some part of the above must have worked because I couldn't perceive any stuttering on today's 20 mile ride. Hurray!

I'm still getting used to the characteristics of the kit though. I found the best tactic at junctions and lights is to drop the font derailleur onto the middle ring just before stopping. The rear cassette can be left on the smallest cog. When the lights change, it's easier to start in this lower gear, then change up to the largest chainring after 10 or 20 metres.

The kit doesn't give quite the acceleration I hoped for but is much better on hills than I expected. I tried using assistance level 4 on the flat at times to extend the range. After my 20-ish miles the battery was nearly empty (indicated) though I don't know how much charge was actually left. I weigh about 85kg and have quite a few hills to contend with. I always pedal (never throttle only) but like to do a decent pace.

Has anyone noticed a difference in range in warmer weather?
 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
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Higher ambient temps does affect range with an increase 10 - 20% I reckon.

Using PAS 4 on the flat is wasteful of battery energy stick to 1 or 2 on the flats saving the other higher assists for inclines/hills then straight back to 1 or 2.
Amps and high assist speed use more range so I usually have cut off assist at 32 - 35km/h/. The more amps applied stress cells more and induces more voltage sag, the kinder you are to the cells the longer a battery will last even one with very good cells. For extended life use high assist only if needed.
Pas 1 uses 13% of max amp rating.
Pas 2 20%.
Pas 3 33%.
Pas4 50%.
Pas5 100%.
 

GaryMc

Finding my (electric) wheels
Dec 25, 2018
11
2
Higher ambient temps does affect range with an increase 10 - 20% I reckon.

Using PAS 4 on the flat is wasteful of battery energy stick to 1 or 2 on the flats saving the other higher assists for inclines/hills then straight back to 1 or 2.
Amps and high assist speed use more range so I usually have cut off assist at 32 - 35km/h/. The more amps applied stress cells more and induces more voltage sag, the kinder you are to the cells the longer a battery will last even one with very good cells. For extended life use high assist only if needed.
Pas 1 uses 13% of max amp rating.
Pas 2 20%.
Pas 3 33%.
Pas4 50%.
Pas5 100%.
Great, thanks for the tips. Good to know!
 

egroover

Esteemed Pedelecer
Aug 12, 2016
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Higher ambient temps does affect range with an increase 10 - 20% I reckon.

Using PAS 4 on the flat is wasteful of battery energy stick to 1 or 2 on the flats saving the other higher assists for inclines/hills then straight back to 1 or 2.
Amps and high assist speed use more range so I usually have cut off assist at 32 - 35km/h/. The more amps applied stress cells more and induces more voltage sag, the kinder you are to the cells the longer a battery will last even one with very good cells. For extended life use high assist only if needed.
Pas 1 uses 13% of max amp rating.
Pas 2 20%.
Pas 3 33%.
Pas4 50%.
Pas5 100%.
I've found pas4 on a par with my crossfire-e on top assist, and as I'm use to that on my commute that's what I've been using with the odd drop down to 3 and 5 for hills. Nealh, are you basing your advice on your 48v 20a Yose setup? I would imagine that's quite a bit more oomph than the standard controller and 36v
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Partly, yes I do get more power from my 48v Yose but also the same applies to my KT/Bafang CST @36v with 17a controller.
My Bafang I use my ailing 29E batteries which are hopeless above PAS 2 for local use, still get 20 miles in pas 2 but only about 12 if I use PAS 3 and only on a fully charged battery I use throttle or PAS 5 then after about 5 or 6 miles lvc comes in due to terrible sag.
 

GaryMc

Finding my (electric) wheels
Dec 25, 2018
11
2
Thinking a bit more about this, my bike is mainly used for a 10 mile trip which saves £4 on the train fare. Using the higher assist, I can do the trip easily in 45 mins, which is about the same as the total train journey time. If I charge the battery daily, and it lasts for 500 cycles, then I will have saved £2000 in train fares. Shelling out £200 on a new battery will still leave me quids in.

The question is - would the battery last 500 cycles if I used high assist most of the time? I guess I'd have to try it to find out.

Living in hilly Scotland, I will unavoidably be using higher assists a fair bit of the time. As I get fitter I will likely dial back the assistance where I can.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Depends on the quality of the cells inside, being one from the big four doesn't mean they will do the 500 cycles if they are crappy 4 or 5a cells, for longevity a 10a rated cell will handle stress and higher discharge better. Fast charging is another factor that will reduce life a 2a charger charging a 4 or 5P (parallel) string @0.2c - 0.25c is better then charging at 5a or more.
High discharge and charge rates both will affect cell life.

Cars etc get away with fast charging as there are 100's of cells in parallel or very large ah pouch format cells, e bikes are limited by weight and size typically only having 4 or 5P and a lot of newer lighter bikes only using 2 or 3P supporting 6 -9ah.

Using top assist all the time you will likely see capacity drop over 12- 18 months but this might only show up in reality if you do longer runs and notice range dropping off.

Better to use it then lose it through little use which makes e-biking expensive for some. Probably why some get disillusioned with the tech as they put a bike away for months on end in a fully charged state and wonder why the battery (expensive replaceable main component) doesn't perform.
 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
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In the long run if you benefit from the riding and enjoy it then money saved is a plus as long as you can stay safe on the road. 2k saved is a holiday, a nice treat or down payment on the mortgage for an earlier retirement or mortgage free living.
45min ride is a good work out for the cardiovascular system, studies have shown that e-biking is as beneficial as riding an unassisted bike. The difference being you don't put so much stress on the heart/bpm is lower.
 
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Olleman

Pedelecer
Jan 7, 2019
126
15
Partly, yes I do get more power from my 48v Yose but also the same applies to my KT/Bafang CST @36v with 17a controller.
My Bafang I use my ailing 29E batteries which are hopeless above PAS 2 for local use, still get 20 miles in pas 2 but only about 12 if I use PAS 3 and only on a fully charged battery I use throttle or PAS 5 then after about 5 or 6 miles lvc comes in due to terrible sag.
Sorry if this is a bit of topic but what differencies do you notice between your Bafgang and Yose hub? The Bafang hub is a bit more expensive so I would imagine some kind of advantage for the Bafang?
 

egroover

Esteemed Pedelecer
Aug 12, 2016
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Smack it up to full assist, if you've got the range or have to charge it every night so what, just enjoy it, that's what I do on the daily commute. However I do put it on eco setting if I want to do a day ride out for 50 miles and 4hr ride, I get more of a work out and don't mind sweating a bit more. As you mention, just put some of your saved bus fare in a whisky bottle to buy yourself a new battery every couple of years
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,990
8,172
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West Sx RH
Sorry if this is a bit of topic but what differencies do you notice between your Bafgang and Yose hub? The Bafang hub is a bit more expensive so I would imagine some kind of advantage for the Bafang?
In use very little, though for hot rodding the Bafang is a bigger motor and likely will take more amps the Yose if required but for me 17 - 20a is all I need for about 20mph in PAS 2.
 

GaryMc

Finding my (electric) wheels
Dec 25, 2018
11
2
Thanks for all you replies. The stuttering has returned a bit, so I might play with the settings. Today it would sometimes take up power after pedalling then cut for a second then come in again. I'm getting used to giving it a touch of throttle to get it 'over the hump' and then it's ok. I used PAS3 quite a bit, with PAS5 for the hills and it did make a difference to the indicated charge left. Well, I think I'll just do what I feel like on any given day. I find that I am still pedalling a lot and getting a bit of a sweat on. The difference is that I am averaging a higher speed and can blat up the hills. So I do feel like I'm getting some exercise and it's nice to be out and about rather than stuck in a traffic jam or on the train.

Having whacked up my credit card balance with my bike upgrade I have a great reason to keep saving on the train fare! I doubt that the big bottle of shiny saved pound coins will ever materialise though.

As for slow charging - the supplied charger is 2ah output and is certainly not fast. Even with just a little top up it takes a few hours to go from red to green. I take your point about not leaving it stored at 100% That is worth remembering, but I think mine will be in use at least a few times per week.
 

GaryMc

Finding my (electric) wheels
Dec 25, 2018
11
2
Alas, after about 150 miles the cutting out problem is much worse. It cuts in and out constantly, for about 5-10 seconds each time. So the PAS is now pretty useless. I had to get home by holding the throttle on for assist, which is a pain as it pulls too much current and makes changing gear a hassle. I'm guessing it's the integrated controller that's at fault and have messaged Yose for a replacement. All the other bits of the kit still works - screen, motor, throttle, brake switches. Dashed annoying!
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
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I think that you should re-check the operation and installation of your PAS. There isn't really any fault in the controller that can make it work like that. It works with the throttle so the main function is correct and it works sometimes with the PAS so there must be a problem with the PAS signal getting to the controller's computer chip.

Take the left hand crank off and put the bike on a stand so that you can see what happens to the inner part of the PAS while you turn the pedal. If it moves and you get no power maybe you damaged it, otherwise see if there's any damage on the cable. Did you damage the cable by pulling a zip-tie too tight?