Full PAS restricted speed vs lower PAS unrestricted,what workes fo you?

minexplorer

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Aug 22, 2017
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Bit of a quandry for me. I want range.I like to go on long rides scraping home on the last cough of the battery.But i also want the WOW factor of PAS on max,5,or i might as well be riding a regular bike.Has anyone managed to find this sweet spot,or is it unobtainable.
I have a bbs01 350w 17.4ah . I tried a friends 250w front hub the other day and realised how superiour 350w with PAS 5 was. My fist ride ,up an about Dartmoor,was full power all the way,what a buzz.It was factory restricted to 15mph.I gave this no thought,it wasnt an issue.I got 35 miles and was happy.Then sadly i tried un resticted speed and couldnt go back.Now i could only scrape 27 miles if i used PAS4 mostly,5 for hills,an 3 the last few miles.Somehow its just not as good. I feel like its truely head an shoulders above a regular bike,when on 5.What an electric motor powered bike should feel like. Ive seen ebikers crawling along on low power,trying to eek out their batteries no doubt and thought,you might as well just have a non elec one.
Recently ive gone back to full power all the time. With the speed cutout reduced to 15 then 17mph.But unlke when i first had the kit ,it now feels unnatural and annoying.Maybe ill get used to it.I doubt it tho.But ive only got 14.5ah to play with now .As this battery doesnt fit my missus bike,id bought it for.
Id reallly like to hear others opinions.What theyve compromised on to suit their riding style ,use etc
 

danielrlee

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May 27, 2012
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There's no magic involved. The more effort you put into pedaling and the less power you ask from the motor, the greater the range you will achieve.

Regarding speed - it kills range.

The following chart illustrates how much power is required to overcome air resistance to maintain a given speed on level terrain.

 

anotherkiwi

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Jan 26, 2015
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There's no magic involved. The more effort you put into pedaling and the less power you ask from the motor, the greater the range you will achieve.

Regarding speed - it kills range.

The following chart illustrates how much power is required to overcome air resistance to maintain a given speed on level terrain.

OOOoooo! Look! A recumbent only requires 480W to reach 45 km/h :p Those of us who want to go far and fast with less power do have that option! :)
 

danielrlee

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OOOoooo! Look! A recumbent only requires 480W to reach 45 km/h :p Those of us who want to go far and fast with less power do have that option! :)
Indeed. A recumbent has roughly half the drag coefficient (Cd) than an upright MTB.

The real aero gains are to be had at 30mph+. Anyone spending lots of time above this speed would be wise to investigate a fairing for their vehicle to decrease the Cd as much as possible.
 

anotherkiwi

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I have seen a couple of guys report that their home made ply or coroplast fairings gave them a 30% increase in speed! :) Yummy, can't wait! :cool:
 

minexplorer

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Aug 22, 2017
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Wow that chart really spells it out.My mtb would use DOUBLE the watts at 20mph compared to 15mph . So to answer my quandry .How to get range and still keep some wow factor.better to lower the speed cut out with high PAS. Rather than un restricted speed and low PAS? What do others prefer? Ive got the impression most derestrict their bikes ,but are either prepared to run on ECO level modes ,or simply dont need longer range.
 

danielrlee

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How to get range and still keep some wow factor
The best way is to start on top of a big hill and let gravity do its thing.

In all seriousness though, there is no magic answer - everything is a compromise. The only real solution to the problem is to get a bigger battery.
 

anotherkiwi

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Jan 26, 2015
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I have tried unrestricted on my previous two but I got over it and usually set the cut off to 27 km/h which just happens to be about 25 km/h on my GPS. I like going further than faster.

These things will change because I have gone to the Dark Side :cool:, I'm bent now and as the graph shows I can have speed and range. I will try setting the cut off at 32 and 40-45 km/h then adopt the one that suits me the most. At 32 km/h I will possibly use the same power I now use at 15 km/h... :)
 

minexplorer

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Aug 22, 2017
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The best way is to start on top of a big hill and let gravity do its thing.

In all seriousness though, there is no magic answer - everything is a compromise. The only real solution to the problem is to get a bigger battery.
Ha,yeah lassoo passing cars...I did orinally buy a 17.4ah but have had to put it on my old gearless hub bike, as the bracket of the 14.5ah i bought for it wont fit .
Im going to do every ride on a diff setting an post results.The comparison will apply broadly so may help others interested in such stuff.
So far.MTB,slightly fat bloke, 14.5ah batt,350w mid drive.
PAS 5 ,assist cut off 17.4 mph=21.3miles- dissapointing
PAS 5 ,assist cut off 15.5 mph=22.4miles -v dissapointing
Tomorrow PAS 4, with 5 on steeper hills ,no assist cut off
 
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D

Deleted member 4366

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Wow that chart really spells it out.My mtb would use DOUBLE the watts at 20mph compared to 15mph . So to answer my quandry .How to get range and still keep some wow factor.better to lower the speed cut out with high PAS. Rather than un restricted speed and low PAS? What do others prefer? Ive got the impression most derestrict their bikes ,but are either prepared to run on ECO level modes ,or simply dont need longer range.
Another thing you can do is electrify a road bike. They have much less drag than an MTB, so not only do they go faster with the same power, but they don't look out of place when going fast. If you see an MTB going faster than 15 mph, it looks very suspicious, but even 30 mph on a road bike looks normal (except uphill).
 

anders.d.moller

Finding my (electric) wheels
Jan 28, 2018
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I have a Koga Road bike with a retrofit 350w rear drive and 17Ah battery. My bike together with the kit weights 17,8 kilos. I'm only 63 kilos. Doing PAS 5 with cut off at 30 km/h I'm getting at least 100 kilometers per charge. Haven't tried 25 though.
 

minexplorer

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Aug 22, 2017
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I have a Koga Road bike with a retrofit 350w rear drive and 17Ah battery. My bike together with the kit weights 17,8 kilos. I'm only 63 kilos. Doing PAS 5 with cut off at 30 km/h I'm getting at least 100 kilometers per charge. Haven't tried 25 though.
My fat arse must have something to do with it.Ive got a feeling rear hub motors are less juicy than a 350w bbs crank drive too. Bike 22kg rider 14.5 stone,tyres 1.95 front 1.75 back ,45psi.
I cant finish my comparison tests with the 14.5ah battery, as ive managed finally,to fit it to my other bike. However with the 17.4ah.
PAS 4 ,5 on hills ,assist cut out 18.5mph = 27.5 miles.
There was plenty of inclines an rough tracks. Interestingly the 6p battery ,on its last drips,climbed the 1.5mile,fairly steep hill to home on PAS 4,with no sag.Thats 2.5amp draw on the cells.The 5p battery prob wouldnt have managed that with 3amps required from them.Any future battery i buy will be 6p.
 
D

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My fat arse must have something to do with it.Ive got a feeling rear hub motors are less juicy than a 350w bbs crank drive too. Bike 22kg rider 14.5 stone,tyres 1.95 front 1.75 back ,45psi.
I cant finish my comparison tests with the 14.5ah battery, as ive managed finally,to fit it to my other bike. However with the 17.4ah.
PAS 4 ,5 on hills ,assist cut out 18.5mph = 27.5 miles.
There was plenty of inclines an rough tracks. Interestingly the 6p battery ,on its last drips,climbed the 1.5mile,fairly steep hill to home on PAS 4,with no sag.Thats 2.5amp draw on the cells.The 5p battery prob wouldnt have managed that with 3amps required from them.Any future battery i buy will be 6p.
You don't need to worry about how many cells are in the battery, except that the battery will be lighter with fewer cells. Nothing spoils a bike more than battery weight, even more so when it's not in the middle of the bike. Samsung 30Q can provide all the current you need at 4P. I use 2P in one of my bikes to get a 1kg battery. The less weight you have, the less power you need.
 

minexplorer

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Aug 22, 2017
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You don't need to worry about how many cells are in the battery, except that the battery will be lighter with fewer cells. Nothing spoils a bike more than battery weight, even more so when it's not in the middle of the bike. Samsung 30Q can provide all the current you need at 4P. I use 2P in one of my bikes to get a 1kg battery. The less weight you have, the less power you need.
Yes d8veh.With helpful input from others on the forum ive been doing a lot of research lately.Ive certainly discovered some surprising stuff. And as you say you have to look much more deeply into cell choice,than just their brand name. Im learning slowly.