January 4, 20197 yr As I've never ridden a crank drive I have no idea of the sort of characteristics it has, all proponents say the crank drive is better for hills than hub motors, but will a 250w motor be sufficient? They have internal controllers so heat dissipation could be a problem with less current handling capability. Please everyone let me have your thoughts. I love crank drives! you get the natural weight distribution and power delivery. Email support@wooshbikes.co.uk about your project, we can discuss it much better. The 48V TSDZ2 is very capable on hills, especially if you fit a double chainring. http://wooshbikes.co.uk/?cdkit#tsdz2 This thread is about PSWPOWER kits, I apologise for the digression.
January 4, 20197 yr BBS power is down to the programming and probably needs a lead and the down load software (free) to enable better power from them. I find with my BBS01 even in level 9, I have to work hard on steep off-road conditions (uneven gravel/treelined routes). For me I expect my issue is lack of leg strength and Asthma, my travel speed on steep inclines off-road is about 6-7mph. One controller has failed with my BBS and this was a factory set one without re-programming. Most seem to opt for the BBSHD for it's very high torque, though also expect speed is also a factor. These need high performance batteries to be at their best. For your requirement's then sounds like 750 or BBSHD is better, max power being around 1kw or more. The decision then is pas drive or torque drive, the latter will supply power in proportion to your input whilst pas requires a gentler cadence. BBS01 typically about 540-648w max output before inefficacy losses , TSDZ is 48v so 768w max output before losses.
January 4, 20197 yr Tony My wife hired an electric Scott bike with crank drive yesterday and we covered most of Dalby forest in North Yorkshire. Obviously getting lost didn't help but we were riding for four hours and she loved the assistance provided by the bike. It's rated at 500w and used half of the battery power during our ride. It supplied adequate power only when pedalling when set to touring by the hire shop. There is a higher setting but she didn't feel the need to use it and battery life would suffer I guess. Btw on a manual bike I was absolutely jiggered.
January 4, 20197 yr Author I love crank drives! you get the natural weight distribution and power delivery. Email support@wooshbikes.co.uk about your project, we can discuss it much better. The 48V TSDZ2 is very capable on hills, especially if you fit a double chainring. http://wooshbikes.co.uk/?cdkit#tsdz2 This thread is about PSWPOWER kits, I apologise for the digression. sent email-Tony.
January 4, 20197 yr Author BBS power is down to the programming and probably needs a lead and the down load software (free) to enable better power from them. I find with my BBS01 even in level 9, I have to work hard on steep off-road conditions (uneven gravel/treelined routes). For me I expect my issue is lack of leg strength and Asthma, my travel speed on steep inclines off-road is about 6-7mph. One controller has failed with my BBS and this was a factory set one without re-programming. Most seem to opt for the BBSHD for it's very high torque, though also expect speed is also a factor. These need high performance batteries to be at their best. For your requirement's then sounds like 750 or BBSHD is better, max power being around 1kw or more. The decision then is pas drive or torque drive, the latter will supply power in proportion to your input whilst pas requires a gentler cadence. BBS01 typically about 540-648w max output before inefficacy losses , TSDZ is 48v so 768w max output before losses. Neal, Thank you for this. So a pas drive needs more pedal power from me up the hills? I've not seen any BBSHD kits for sale. Ideally I would just like a kit that is road legal and has enough grunt to get me up those gravelly ridges in the New Forest without me sweating. I want to enjoy the scenery and listen to the wildlife not be puffing and panting along those tracks.
January 4, 20197 yr So a pas drive needs more pedal power from me up the hills? No not really, PAS supplies power depending on the level of assistance you select, like your hub motor, torque sensing ups the power to match your input, more power from you, more power from the motor.
January 4, 20197 yr Indeed, if the motor is powerful enough and appropriately geared, you can get up will with NO effort with PAS; just keep pedalling fast enough the PAS engages (hardly any speed at all) but slow enough you are not actually pushing the gears. I think typical torque multiplier systems have 250% or 300% maximum multiplication, so (at 300%) you need to provide at least 1/4 of the power, while the motor provides the other 3/4.
January 4, 20197 yr Indeed, if the motor is powerful enough and appropriately geared, you can get up will with NO effort with PAS; just keep pedalling fast enough the PAS engages (hardly any speed at all) but slow enough you are not actually pushing the gears. I think typical torque multiplier systems have 250% or 300% maximum multiplication, so (at 300%) you need to provide at least 1/4 of the power, while the motor provides the other 3/4. I keep the TSDZ2 with throttle in stock. In case your legs are tired, you can use the throttle to ride home without pedaling. http://wooshbikes.co.uk/cart/#/product/uid-206-tsdz2t/tsdz2-cd-kit-48v-15a-250w-with-throttle-kit
January 4, 20197 yr Neal, Thank you for this. So a pas drive needs more pedal power from me up the hills? I've not seen any BBSHD kits for sale. Ideally I would just like a kit that is road legal and has enough grunt to get me up those gravelly ridges in the New Forest without me sweating. I want to enjoy the scenery and listen to the wildlife not be puffing and panting along those tracks. 750 bbs or BBSHD not road or off-road legal only TSDZ is legal as it is marked 250w.
January 5, 20197 yr Surely none of them is legal if a throttle is fitted unless it is very constrained as to how it can operate?
January 5, 20197 yr Surely none of them is legal if a throttle is fitted unless it is very constrained as to how it can operate? The banning of the throttle is often misunderstood. Throttles are not banned, only the twist and go throttle is banned on factory made bikes. it is applicable only to the manufacturers and importers. Customers are not prosecuted for having it fitted or using it. Indeed, throttle is usually supplied as a separate item, for the customer to plug in as and when he/she needs it.
January 5, 20197 yr The banning of the throttle is often misunderstood. Throttles are not banned, only the twist and go throttle is banned on factory made bikes. it is applicable only to the manufacturers and importers. Customers are not prosecuted for having it fitted or using it. Indeed, throttle is usually supplied as a separate item, for the customer to plug in as and when he/she needs it. In the UK - it is a UK exception do not think you can use one on holiday on the continent. Of course there are bikes equiped with throttles here but they are not legal whether kit or not.
January 5, 20197 yr In the UK if you have a throttle after 2016 it can only be actuated after pedalling, if it is stand alone use it is not legal.
January 5, 20197 yr Author OK guys, I get what you are all saying, and I agree, legal is best. However, if I can't get a kit with enough grunt to assist me up those gravelly hills without sweating too much, then I'll go for a 750w kit. So far no-one has said that a 250w kit is actually capable of doing this. I don't want to spend the best part of £6-700 and still be disappointed, I would rather have the illegal kit and just use it off-road.
January 5, 20197 yr So far no-one has said that a 250w kit is actually capable of doing this. Depends how fast you want to go up. 250W will manage most hills so long as you use the gears sensibly and put in a small amount of effort yourself. Cycling around north of Romsey (where it is at least as hilly as the New Forest) I have found only one hill which defeats my 250W rear hub motor. That is Cow Drove Hill out of Kings Sombourne : I don't know how steep it is (no signs as it is a back road), but smaller cars struggle with it creeping up in low gear. I can barely walk up it pushing the bike! I'm only beginning to walk properly again after about 2 years being crippled with an arthritic knee. This means that I can't add much muscle power, but find 250W perfectly adequate and managing most hills between 7 and 10MPH.
January 5, 20197 yr OK guys, I get what you are all saying, and I agree, legal is best. However, if I can't get a kit with enough grunt to assist me up those gravelly hills without sweating too much, then I'll go for a 750w kit. So far no-one has said that a 250w kit is actually capable of doing this. I don't want to spend the best part of £6-700 and still be disappointed, I would rather have the illegal kit and just use it off-road. the kits I sell are usually good for climbing up to 15% gradient without sweating. The BBSHD 1000W can go a bit higher, 20%. How often you need that extra ability?
January 5, 20197 yr That is Cow Drove Hill out of Kings Sombourne Looking at Cow Drove Road on https://gb.mapometer.com/cycling it peaks briefly at 23.9%. Probably exaggerated by sampling and noise, but the bottom section is over 20% for a big enough chunk to be reliable.
January 6, 20197 yr Author Looking at Cow Drove Road on https://gb.mapometer.com/cycling it peaks briefly at 23.9%. Probably exaggerated by sampling and noise, but the bottom section is over 20% for a big enough chunk to be reliable. Guys- You see this is another thing, I have not come across this new % thing with hills. I presume a 25% is a one in 4 gradient, is this right? Most of the hills in the New Forest are not that steep, probably more like a one in 7, although on some ridge paths there are some real doozies much steeper, but short. At the moment I just get off and push.
January 6, 20197 yr My 250w 8fun cst hub in pas 5 outputs 800w @20a plenty for a burst up a steeper incline, usually I only use pas 2 or 3 as does my 350w Yose. Although the top end of the controller ampage isn't used much it is there if needed, other wise just means lower pas levels have a bit more nip to them. Typical 5 level pas system will have % range of 13 (1), 20 (2), 33 (3), 50(4) & 100(5) of available amps.
January 6, 20197 yr Guys- You see this is another thing, I have not come across this new % thing with hills. I presume a 25% is a one in 4 gradient, is this right? Most of the hills in the New Forest are not that steep, probably more like a one in 7, although on some ridge paths there are some real doozies much steeper, but short. At the moment I just get off and push. https://www.bicycling.com/racing/a20046569/the-10-toughest-climbs-of-the-2017-tour-de-france/ https://www.cyclingweekly.com/news/racing/vuelta-a-espana/the-vuelta-a-espana-will-take-on-an-incredibly-steep-31-climb-and-these-photos-show-just-how-tough-it-is-345302 Anything over 17% is either hard work or a really low bottom gear on a pedelec. 25% the road climbs 25 cm every metre, whether the metre is measured on the hypotenuse or the long side of the triangle is up for interpretation.
January 6, 20197 yr My 250w 8fun cst hub in pas 5 outputs 800w @20a I guess that means you have a 48v version, so you are getting a bit more than the 48V TSDZ2 that Woosh talked about earlier? 25% is a one in 4 gradient, is this right? I believe so; 1 in 7 is about 14%. I think they are always quoted vertical distance against road distance, not against horizontal distance. Doesn't make much difference for small slopes, but starts to be significant at 1 in 3. At the moment I just get off and push. Most eBikes have a walk assist feature which will power up to 4mph or so. You might want to double-check before you commit to any particular system.
January 6, 20197 yr Author My 250w 8fun cst hub in pas 5 outputs 800w @20a plenty for a burst up a steeper incline, usually I only use pas 2 or 3 as does my 350w Yose. Although the top end of the controller ampage isn't used much it is there if needed, other wise just means lower pas levels have a bit more nip to them. Typical 5 level pas system will have % range of 13 (1), 20 (2), 33 (3), 50(4) & 100(5) of available amps. https://www.bicycling.com/racing/a20046569/the-10-toughest-climbs-of-the-2017-tour-de-france/ https://www.cyclingweekly.com/news/racing/vuelta-a-espana/the-vuelta-a-espana-will-take-on-an-incredibly-steep-31-climb-and-these-photos-show-just-how-tough-it-is-345302 Anything over 17% is either hard work or a really low bottom gear on a pedelec. 25% the road climbs 25 cm every metre, whether the metre is measured on the hypotenuse or the long side of the triangle is up for interpretation. Kiwi- Blimey, I haven't seen the term hypoteneuse since I left college in 1970. Then it was in relation to vector diagrams, never really did get the hang of them! It was a bit like propagation theory, I sort of got it, but not really, a lot of that stuff was a bit over my head to be honest I just sort of scraped through my exams for tv engineering. Tony
January 6, 20197 yr Author I guess that means you have a 48v version, so you are getting a bit more than the 48V TSDZ2 that Woosh talked about earlier? 25% is a one in 4 gradient, is this right? I believe so; 1 in 7 is about 14%. I think they are always quoted vertical distance against road distance, not against horizontal distance. Doesn't make much difference for small slopes, but starts to be significant at 1 in 3. At the moment I just get off and push. Most eBikes have a walk assist feature which will power up to 4mph or so. You might want to double-check before you commit to any particular system. Thanks Sjpt- Very helpful and something I can actually understand. Cheers, Tony.
January 6, 20197 yr Author My 250w 8fun cst hub in pas 5 outputs 800w @20a plenty for a burst up a steeper incline, usually I only use pas 2 or 3 as does my 350w Yose. Although the top end of the controller ampage isn't used much it is there if needed, other wise just means lower pas levels have a bit more nip to them. Typical 5 level pas system will have % range of 13 (1), 20 (2), 33 (3), 50(4) & 100(5) of available amps. Neal, Thank you but I haven't a clue as to how this relates to whether or not a 250w crank motor will actually assist me up these hills. They are not that steep, just have lots of gravel and water gullies running through them. The front drive 500w Whoosh Sunbear I had handled them with ease, but the front wheel on gravel caused a few mishaps, it was just downright dangerous for this old body, so I got the Freego Eagle with 250w rear hub motor. It just can't cope with the hills, it's pretty useless as a pedelec on them as I have to put in 80% of the effort required. I still don't know the answer to my original question, will it be any better than the Freego Eagle? If so by how much? I don't want to spend £6-700 on a kit that is no better on these hills than the one I've already got-what is the point of that? I am really grateful for you all for your replies here, there is nothing better than advice from those who have been there. I'm just more confused than ever, Tony
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