Which Conversion

[willsie01]

I'm adopting cycling as a way to improve my fitness while I'm out and about by replacing buses and the car relatively locally.
My starting level of fitness is very poor as I've had leg/back issues for some years that required surgery 6 months ago quickly followed by an unexpected triple bypass operation 3 months ago. After getting my bike, a Trek T30 Hybrid, out of the shed where its stood unused for some years, cleaning it up and replacing the tubes and tyres, I've been out for a few short rides to get acclimatised to riding again. If the terrain around me was flat I wouldn't consider an electric bike as I would just work on gradually building up my fitness but it's hilly enough to be too much of a challenge for my current level of fitness to cope with. Hence I'm considering an e bike. I'd like one that wouldn't provide any assistance when I'm on the flat, but would kick in to provide it when I'm going uphill. Could this be automatically detected by the kit? I like the idea where my bike would behave exactly as a manual when the motor isn't providing assistance. So it would freewheel in the same way and have the same gearing. Am I right that a mid conversion would be the best option for this? The more intelligent the conversion kit is the better for me. So is there one that would sense the assistance I need and provide it automatically? What kits would suit me?

 

[Woosh]

is this your bike?

https://www.thebikelist.co.uk/trek/t30-2012

Assuming it is, 700C wheels, 3x7 gears, 7-speed SRAM cassette.

The bike can take front, rear or middle motor, it will look equally good with a downtube battery or a rear rack battery.
If you want easy removal, then I would recommend the front XF07 motor + rack battery.
http://wooshbikes.co.uk/cart/#/product/uid-221-xf07rackkit-15ah/xf07-front-hub-kit-with-15ah-rack-battery

If you want excellent traction then I would recommend the rear XF08C + downtube battery. It's a bit more work to install but gives better torque.
http://wooshbikes.co.uk/cart/#/product/uid-177-xf08c-17ah/xf08c-rear-hub-kit-with-17ah-battery

If you want a middle motor, then I would recommend the Bafang BBS01B.
http://wooshbikes.co.uk/cart/#/product/uid-178-bbs01-17ah/bbs01b-cd-kit-with-175ah-36v-hl-battery

All these kits are road legal.

 

[willsie01]

Yes, that's mine, but mine's a tad earlier then 2012 but had very little use because of health issues I've had since buying it. It is, 700C wheels and 3x7 gears.



When you say easy removal are you talking about the battery for security?

I'll look at your suggestions.

Thanks

John

 

[Woosh]

Hi John,

When you say easy removal are you talking about the battery for security?

The battery has lock and keys. You don't need the key to ride the bike, the key is needed only to unlock the battery from the rack or the carrier if fitted to the downtube.

you can see how the battery is mounted inside its rack and the lock:

The XF07 front hub motor is easiest to remove, in case you want to replace tubes and tyres.
The rack kit is also easiest to install, only 4 bolts. So the combination front motor + rear rack is a bit quicker to install compared to the other kits.
If you want to go with front motor and rack battery, you would undo the 4 bolts on your existing rack and bolt the new racks in its place, re-using the same 4 bolts. It is straightforward.
Release the front brake, drop the wheel, move the tyre and tube over to the new wheel and install the new wheel in its place.
All the kits have both throttle and pedal assist.
you can also simplify the installation if you don't install the throttle.
For a minimal installation, you only need to install the motor wheel, the pedal sensor, the battery and mount the LCD to the handlebars.

 

[vfr400]

You need to determine whether you have a free-wheel or free-hub rear gear set.
here the free-hub is on the left. you can recognise it by its characteristic retaining collar on top of the smallest cog. Another way is to count the teeth on top gear. A free-hub would normally habe 11 or 12 and a free-wheel 13 or 14, though there can be cross-overs.

 

[Woosh]

You need to determine whether you have a free-wheel or free-hub rear gear set.

his bike is fitted with a 7-speed SRAM PG730 12T-32T.
If he goes for the X08C kit, I can fit a new 7-speed cassette for him for £14.
However, for first conversion, the XF07 front hub + rear rack is the best tried and tested route.
I have even developed a method of installation for those who have no special tools, only a set of allen keys and an adjustable spanner are all they need.

 

[Benjahmin]

Any electric conversion is going to be a bit more hands on to control than you are asking for. Any geared hub motor will freewheel when not in use giving no detectable resistance. There are power level settings on the handlebar control (levels 1-5) and most have a zero setting. So you could ride on the flat on zero and up the level for hill climbing. Having said that, once you have experienced the assist, riding without it maked you really aware of the weight of the bike. Many new pedelecers come on here complaining that their motor gives resistance when turned off but, mostly, it's just the weight. So you may end up cycling using power most of the time. That's OK, you will still get the health benefits you want, as many will testify to.
My experience says that hub motors are the easiest to install and the most reliable.

 

[D C]

However, for first conversion, the XF07 front hub + rear rack is the best tried and tested route.
I have even developed a method of installation for those who have no special tools, only a set of allen keys and an adjustable spanner are all they need.

I've used both these kits and been happy with each of them, Woosh is an excellent company to deal with and has top class after sales.
I do much prefer the feel of the rear motor with down tube battery but as stated the front wheel kit was easier to fit though in both cases I had to carefully file out the dropouts to deepen them, not too difficult but has to be done properly.
With the rear wheel kit I also had to spread the stays a little to fit the extra width of the hub motor. For your requirements I would think the front hub will do all you need but my choice for a front hub kit would be the version with down tube battery rather than rack, the bike is much less top heavy and rides better also the controller is integrated with the battery holder making for a much neater and simpler fitting.
http://wooshbikes.co.uk/cart/#/product/uid-197-xf07kit-17ah/xf07-front-hub-kit-2026700c-with-17ah-battery
I haven't any experience of mid drive kits so maybe someone will come along who can offer more advice on those.
Dave.

 

[Nealh]

Don't be fooled that the bikes will ride easily without power when fitted as if you were riding an unpowered bike, to an extent they do in lower gears on level ground and once you get moving they aren't to bad and will depend on how fit or strong a peddler you are. They do freewheel but as mentioned the extra weight/mass of the hub is centrally located, on inclines you will definitely feel the extra weight without power.
With that said I use rear hub bikes and find them more reliable then the BBS01 which I have had issues with over the years.

 

[sjpt]

Glad you followed through from the CTC page. We have a Woosh XF07 conversion on our tandem and are very pleased. A little underpowered for that (Woosh warned us, but no sensible alternative available in the right wheel size at the time); enough for what we want to give that critical help on the hills, but we still need low gears and our grunt. It would certainly be good for a solo in most cases.

Depending on budget it may be worth considering a new bike: it'll be around £600 for conversion or £1000 for complete bike. (Woosh a good choice here too, but there are plenty of other good ones around)

On the kit make sure you take into account battery size which is a significant part of the total, and controller which makes a big difference to smooth efficient running. Quite a few kits out there look cheaper, but by the time you take those details into account the price difference isn't that great.

 

[KirstinS]

Glad you followed through from the CTC page. We have a Woosh XF07 conversion on our tandem and are very pleased. A little underpowered for that (Woosh warned us, but no sensible alternative available in the right wheel size at the time); enough for what we want to give that critical help on the hills, but we still need low gears and our grunt. It would certainly be good for a solo in most cases.

Depending on budget it may be worth considering a new bike: it'll be around £600 for conversion or £1000 for complete bike. (Woosh a good choice here too, but there are plenty of other good ones around)

On the kit make sure you take into account battery size which is a significant part of the total, and controller which makes a big difference to smooth efficient running. Quite a few kits out there look cheaper, but by the time you take those details into account the price difference isn't that great.

The xf07 I have overvolted with startling results

The torque and speed from such a small motor at 48v is astonishing

I do think this is a motor that can handle a bit more amps than most give it

 

[sjpt]

My controller is 17 amps. I'm not sure the battery (Hailong 13aH 36v) would like to deliver much more; big drop on voltage under load. I might think some time about upgrade to 48v, but it would mean quite a few changes.

The voltage sag is more than I would expect from 17amp and the quoted battery characteristics (https://lygte-info.dk/review/batteries2012/Samsung ICR18650-26H 2600mAh (Pink) UK.html). When I get my thoughts properly together I'll be asking more detailed questions to try to understand all the causes of voltage sag.

 

[Nealh]

The 26H is rated 5.2a max, it delivers the same capacity as 26F but sags a lot more then 26F, so not surprising about the V sag. In reality it's actual true operating discharge for a reasonable life is 2a per cell in a 5p config .

My 26F pack used with a 17a controller with the Qxydrive kit managed 18 months before I noticed a 30% drop in capacity = range.

 

[sjpt]

The 26H is rated 5.2a max, it delivers the same capacity as 26F but sags a lot more then 26F, so not surprising about the V sag. In reality it's actual true operating discharge for a reasonable life is 2a per cell in a 5p config .

My 26F pack used with a 17a controller with the Qxydrive kit managed 18 months before I noticed a 30% drop in capacity = range.

As the battery is 5p the 17a is only 3.3a per cell. We (tandem) usually ride at level 2/5, 3/5 on bigger hills (KM 529). That should bring it under the 2a. Looking at the charts (https://lygte-info.dk/review/batteries2012/Samsung ICR18650-26H 2600mAh (Pink) UK.html) the 3a line shows a drop about 0.2v per cell, or 2v for the battery pack. I'd expect the meter readings to be at about 2v per bar, so to lose 1 bar under full load; but it actually loses 2 bars under 3/5 load. Is there some other significant resistance (around the scale of cell internal resistance) between the cell pack and the meter? It isn't that important, we are pretty happy with the way it behaves, but I don't like not quite understanding.

 

[Woosh]

As the battery is 5p the 17a is only 3.3a per cell. We (tandem) usually ride at level 2/5, 3/5 on bigger hills (KM 529). That should bring it under the 2a. Looking at the charts (https://lygte-info.dk/review/batteries2012/Samsung ICR18650-26H 2600mAh (Pink) UK.html) the 3a line shows a drop about 0.2v per cell, or 2v for the battery pack. I'd expect the meter readings to be at about 2v per bar, so to lose 1 bar under full load; but it actually loses 2 bars under 3/5 load. Is there some other significant resistance (around the scale of cell internal resistance) between the cell pack and the meter? It isn't that important, we are pretty happy with the way it behaves, but I don't like not quite understanding.

I think for 3.3A current draw, the sag is about 10%-11%.
If you look at the amount of energy lost when discharging at 3A, it's 9.8WH (red) -8.8WH (yellow), about 10% so 3.3A would lose about 11%. From there, I would say the voltage sag is about 3.6V for the 17A pull.