Boost Conversions

[Jdsk]

A happy user:
viewtopic.php?p=1944841#p1944841

And my second conversion kit should arrive... today.They have a new design of control unit and I'll report on that when it's available, probably next month.

Jonathan

[Jdsk]

Just ridden our Boosted tourers from Berlin to Hook of Holland, That's their first long test.

Never discharged below half capacity.

Sometimes on hills I couldn't maintain enough road speed to it to join in. So I walked.

Very impressed.

Jonathan

[Jdsk]

A bit more on that tour, as requested in another thread.

Started in Berlin and finished at Hook of Holland. Followed EV2/R1 in Germany and our own route in the Netherlands. No mountains but quite a lot of up and down when skirting the Harz, and many of the cities and towns were on rises or by gorges.

Typically 50 to 60 km a day.

We're below average body size. Bikes were steel Galaxies. Luggage was two panniers and a front bag each. I carry a lot of tools and spares. Just before setting off we decided not to take the camping equipment.Mass of the Boost battery is 1.4 kg and of the charger 0.4 kg. We hit the hot patch halfway through so were starting with about 4 kg more fluid than usual between us

The batteries were OFF nearly all of the time. ON for climbing when needed, sometimes when there were lots of junctions and stopping (I hadn't previously realised how helpful this could be), and sometimes when batting next to big roads.

Never discharged below half capacity. Took an hour or two to recharge them.

Jonathan

[Paulatic]

A bit more on that tour, as requested in another thread.

Started in Berlin and finished at Hook of Holland. Followed EV2/R1 in Germany and our own route in the Netherlands. No mountains but quite a lot of up and down

Jonathan

Thanks for the info.
I put the route into CT and total ascent, living where I do, I’d refer to your up and down as a flat ride. My usual 40km ride has half the climbing your whole route had.
Would it be fair to assume a normal hilly 40-50 km would be at their assistance limit?

[Cugel]

Started in Berlin and finished at Hook of Holland. Followed EV2/R1 in Germany and our own route in the Netherlands. No mountains but quite a lot of up and down

Jonathan

I put the route into CT and total ascent, living where I do, I’d refer to your up and down as a flat ride. My usual 40km ride has half the climbing your whole route had.
Would it be fair to assume a normal hilly 40-50 km would be at their assistance limit?

The "assistance limit" of any motor/battery system for an e-bike can be measured objectively in terms of motor power profiles, battery capacity and the efficiency of the system as a whole at putting the required power addition down on to the road at the tyre. A Boost system is at the lower end of the range across the available e-bike motor/battery systems but ......

Another way to measure a more subjective "assistance limit" of a system is to consider the amount and type of assistance the user requires of it. Jdsk found the Boost system more than adequate, going by the description of its use on a tour. This is partly the kind of journeys involved that the system is asked to assist and partly the already extant fitness of the rider.

The seriously unfit or otherwise low-power-producing individual would probably need one of the higher power motors; and probably a larger capacity battery to do longer routes. Some who are quite sporty seem to use mid or even high-power systems and battery capacities to help only with what they see as the tedious parts of any ride (e.g. mountain bike downhillers using a motor to get to the top of the ascents).

Another factor is the assistance-range of any e-bike system. Some seem to use every mode, from "usually none" via "a little bit" right up to "a momentary big boost to get up the 1 in 4 hill-bit". The routes ridden matter too.

In short, the assistance limit" of any e-bike motor system needs to be judged not just by its inherent power/energy-capacity but by what the user intends to do with it and how much power & energy such usage demands given the user's own power & energy capabilities.

[Jdsk]

A bit more on that tour, as requested in another thread.

Started in Berlin and finished at Hook of Holland. Followed EV2/R1 in Germany and our own route in the Netherlands. No mountains but quite a lot of up and down.

Thanks for the info.
I put the route into CT and total ascent, living where I do, I’d refer to your up and down as a flat ride. My usual 40km ride has half the climbing your whole route had.
Would it be fair to assume a normal hilly 40-50 km would be at their assistance limit?

Sorry, I can't make it much more quantitative. I wasn't keeping a log. Using the cycle.travel data is very sensible: in Germany we were following its R1 route, with the exception of where the R1 had been moved (!), closed paths, and diversions to find a bed.

Boost's current (!) statement is :
Long-Range: Our 252Wh / 7Ah battery offers roughly 35 miles of range for typical riders. More than enough for most commutes, or longer days out in the saddle*
*Range will vary depending on multiple factors, including terrain, rider weight, type of bike etc. 35 miles is a guideline only
https://boostbike.uk/completeboostkit

Of course you could carry a second battery...

Jonathan

[bikes4two]

> Getting used to what range you'll get out of your particular battery comes with the experience of repeated rides over different terrains with different levels of assist.
> I've been riding my TSDZ2 machines for around 5 yrs now and have a pretty good handle on what assisted mileage I can get for any particular ride.
> It was a learning curve but this is how I did it:
- I'd start the ride with a full battery
- at the end of the ride I'd note the miles ridden and terrain, the battery voltage and then fully re-charge the battery via a DC coulomb meter (Ali Express - maybe £20) and note the watt-hours of energy needed.
- with this information, simple arithmetic gave the watt-hrs per mile (5Whr/mile or less for me)
- a useful figure if you know the total watt-hrs capacity of your battery - this can be found by running a fully charged battery through the coulomb meter into a resistive dummy load (and through a low voltage cut-off device to ensure the battery does over-discharge). Alternatively, use 85% of the battery's quoted capacity (I say 85% as quoted battery capacities are often calculated by discharging to a very low voltage, lower than the bike's controller or BMS would normally allow).

All too much for some I know but a useful rig for those who can put together this simple electronics gizzmo.

[stodd]

Boost's current (!) statement is :
Long-Range: Our 252Wh / 7Ah battery offers roughly 35 miles of range for typical riders. More than enough for most commutes, or longer days out in the saddle*
*Range will vary depending on multiple factors, including terrain, rider weight, type of bike etc. 35 miles is a guideline only
https://boostbike.uk/completeboostkit
Jonathan

I think that 35 miles on that tiny battery will probably be on the flat with lowest level of assist, good roads and a light rider.

Does anyone else have the problem that https://boostbike.uk/completeboostkit is illegibly blurred (PC,both Chrome and Firefox)? Maybe cookie related; waiting for a Cookie choice, but not displaying that choice even with scrolling. Worked on Edge, where the cookie choice showed up at the bottom of the screen (no scrolling needed).

[rjb]

Here's another way of checking your battery. After 96 Kms I put my battery on charge and fitted a power meter to measure it's consumption to full charge. So power consumed was 360 watthr to fully charge the battery which had been used for 96 Kms.

This equates to 10 watthr powers us for every 2.5 Km.

This is on a Tongsheng mid drive on our tandem with a 14 amp hour 36v battery which runs on the lowest setting until we hit a hill.

So in theory our battery should be good for approx 120 km
But in real life we recharge it after 100km as we notice it's performance starts to decline. It's been good for over 15,000 miles so far using 2 batteries which get swapped around so we always have a fully charged spare at home.

[bikes4two]

Hi 'rjb' - yes using one of those power meters is another way of estimating your consumption per unit distance, and TBH a simpler way than I described above.

I think that your estimated range of 120km is greater than this in that the measured power includes the conversion losses of the battery charger (230v ac to 42v dc). Efficiency of such charges is typically around 85% - 90% so in the best case 120Km/0.9 = 133km.

Your 14Ah battery is 504 Wh (36*14) and I'd guess on the TSDZ2 lowest setting you'll be consuming somewhere arounf 5-7 Wh/miles giving a theoretical range of 72 - 100 miles (116-161 km).

I say theoretical as the 14Ah capacity figure is based on discharging each LiOn cell down to 3.0v or even 2.8v whereas the LVC (Low Voltage Cut-off) point on the TSDZ2 controller is likely to be around 3.1v per cell.

In practice the 14Ah battery may only give useful power of around 450 ish Wh.

Battery overal life: assuming each of your two batteries has has done 7500 miles each (12000km) and for the sake of the argument lets assume a full battery discharge happens for you after 120Km, then each of your batteries has been through 100 full charge/discharge cycles.

Depending on the cell quality used in your battery packs, they should be good for 300-500 charge/discharge cycles before their capacity drops to 80% of their 'when new' capacity - loads of miles to go then

[Jdsk]

Here's another way of checking your battery. After 96 Kms I put my battery on charge and fitted a power meter to measure it's consumption to full charge. So power consumed was 360 watthr to fully charge the battery which had been used for 96 Kms.

This equates to 10 watthr powers us for every 2.5 Km.
...

That's energy, not power.

...

Please could general discussions of eBiking be discussed somewhere else, so that this thread can concentrate on Boost kits (similar for those about other specific makes). That will make it easier for future possible buyers.

Thanks

Jonathan

[arnsider]

Having transfered my Boost motor from the 700 kinesis T2 wheel to the 26 inch Thorn Nomad wheel, I have a much heavier bike that I have down graded to short local runs and shopping. However, I need a new chain on my Cube, so on Sunday, I rode the Nomad on a flatish 35 mile route crossing from Arnside to Grange by train and coming back over Methop, Levens and across the marsh to Sandside.The Nomad is low geared with a treble chainwheel and it performed okay on the few short climbs. I carried a second battery in my rack top bag, but didn't need it. Getting home, I found I had two bars left which isn't at all bad.

[Jdsk]

How much of the journey was with assistance on?

Thanks

Jonathan

[arnsider]

Well, at a very rough guess, I'd say 50-60% The weather was optimal in that there were no appreciable headwinds to slow my progress and use power or cool the battery which can also lower power.
These Boost motors are very useful as an assist though they won't perform as well as an E bike proper.
I have a Cube 800 and the difference is staggering.
The advantages of the Boost are;
Its light weight that helps lifting the bike into trains. and general manhandling.
It flies into the back of my VW Caddy, whereas the Cube needs a plank!!!
Spare batteries are easily carried in any sort of bike bag, saddle bag, pannier or rack top.
The controller is brilliant and wireless. It communicates with the battery power delivery by blue tooth.
It doesn't have an Odometer but you can get around that with a smart phone app- Map my ride or a cycle GPS.
As an aside, the motor wheel slips into my Nomad drop outs much easier than it did into the Kinesis drop outs.
Is this because alloy frames are slightly tighter than Reynolds 531?

[arnsider]

jdsk mentioned a new design of control unit. This was offered to me by my local boost dealer Malcolm Turner.
I declined as I was budget concscious and quite happy with my original.
I cannot find a reference to this upgrade in the Boost online data.
Could you kindly explain the upgrade here please?