Most powerful eBike for long uphill journeys?

[GLJoe]

It's called rotational inertia. It's harder to get something heavier moving, and keep it moving, than it is something that is lighter.

I'm afraid that's only half correct. You are lumping together two separate things. Yes its harder to GET something heavier moving, but once its reached a certain velocity, it only needs more force to CHANGE its velocity, not to keep it moving. Newtons laws of motion!
There might very well be other variables such as different wind resistance, different rolling resistance values if one were to compare a skateboard wheel to a monster truck, but we are not doing that here, we are simply talking about a heavy bicycle v a light one. Once both are travelling at a steady 15mph, the differences in these other losses will be negligible, and thus the force needed to maintain the same steady speed will be the same.

 

[Zlatan]

A

I'm afraid that's only half correct. You are lumping together two separate things. Yes its harder to GET something heavier moving, but once its reached a certain velocity, it only needs more force to CHANGE its velocity, not to keep it moving. Newtons laws of motion!
There might very well be other variables such as different wind resistance, different rolling resistance values if one were to compare a skateboard wheel to a monster truck, but we are not doing that here, we are simply talking about a heavy bicycle v a light one. Once both are travelling at a steady 15mph, the differences in these other losses will be negligible, and thus the force needed to maintain the same steady speed will be the same.

With one exception...big wheels have less rolling resistance,to do with angles and wheel mounting imperfections on road/ track..
See what your top speed is on a skateboard on rough track...mtb wheel rolls over it easy..
On perfect surface would make no difference, but there is no such thing....

 

[EddiePJ]

Five of us carried out a very non scientific test a couple of years ago in respect of which rolled fastest down a hill, 26", 27.5" and 29" One lad was on a 26" bike, two on 27.5 and two on 29" The road that we choose was about one mile long, and just a gradual slope. No pedaling was carried out, and it wasn't long before the 29" bikes began to slowly pull away from the 27.5" bikes, and the 27.5" bikes pulled away from the 26" bike. As the speed slowly increased on all bikes, the distance that the 29" bike pulled away, rapidly increased. Had I not been there, I would never have believed just how much difference that there was between the wheel sizes.

Back on the topic of climbing, Once I have sat and worked things out properly in respect of using it and analysing the stats, I'm going to have fun with this over the next two weeks. A few screen shots.

 

[Woosh]

in physics, the rolling resistance is proportional to the square root of sinkage depth divided by the wheel diameter.
Sinkage is less if you run your tyres at higher pressure.

 

[Zlatan]

in physics, the rolling resistance is proportional to the square root of sinkage depth divided by the wheel diameter.
Sinkage is less if you run your tyres at higher pressure.

Where do you find them Woosh ?
Again a caveat for the above...if you are running to hard pressure ( it is an mtb thread after all) wheel will lift over stones rather than absorb the stone into it...so for off road there really is an optimum pressure..enough to have least resistance on smoothish but soft enough for tyre to work as it should..
Eddie..
Were all riders same weight? The heaviest will always win down hill races..has more gravitational force to windreresistance..( its why generally top down hill skiers are heavy .

 

[EddiePJ]

All pretty much the same weight and size. As said, it was nothing scientific, just a bit of fun when were out on a ride one day.

 

[GLJoe]

A

With one exception...big wheels have less rolling resistance,to do with angles and wheel mounting imperfections on road/ track..
See what your top speed is on a skateboard on rough track...mtb wheel rolls over it easy..
On perfect surface would make no difference, but there is no such thing....

"There might very well be other variables such as different wind resistance, different rolling resistance values if one were to compare a skateboard wheel to a monster truck, but we are not doing that here, we are simply talking about a heavy bicycle v a light one"

 

[topographer]

Wher it is an mtb thread after all

No, the thread has been hijacked. It was originally about someone with one lung getting up a 20% hill because they feel trapped in their village.

 

[mountainsport]

in physics, the rolling resistance is proportional to the square root of sinkage depth divided by the wheel diameter.
Sinkage is less if you run your tyres at higher pressure.

Also by losing weight can help too.

MS.

 

[EddiePJ]

Hey all,

Thanks again for helping me in the journey. Here's some more info, hopefully you can help me decide whether this carerra bike is right for me and will do the job.

As one of you cleverly noticed, my name does indeed reflect my current situation. I only have 1 lung, this is due to a car accident I had when I was younger.

As I have got older, my working lung has began to experience numerous issues, and fresh air (no panting) is incredibly soothing for me.

I also use an inhailer, I'm 35yo. Im not fit, but I'm not fat or overweight etc. I'm around 5ft 8" and ~67kg.

I have absolutely no lung capacity whatsoever, puffing and panting is incredibly painful and while not dangerous, can cause me to have panic attracts etc due to feelings of suffocation etc. So I tend to avoid anything that may affect me this way.

However, gliding along a flat surface peacefully on a bike, Breathing in the sea air really does help me physically, mentally and emotionally.

I live in a rural area, in a small village at the bottom of a 20% incline around 3/4 mile long. I can cycle around the village, however, that's around 3 minutes of 1 flat straight road, not much fun to be had there.

I would like to be able to ascend the incline, without really excerting much more effort than if I was still on the flat surface. I'm trying to find a bike that will add power and assist me up the hill without me having to standup or really push harder on the pedals. (The extra pressure in my lung/chest really isn't good for me)

I can however cycle for hours on a flat surface, walk on a flat surface without issue and I don't have any other major show shopping ailments that would affect this.

My budget is (or I would like it to be) around £1000 as then I could use the BTWS to get some discount. However, if there is not a good bike in this range, then of course I will consider other options of say up to £1500ish.

However, this will cause a sever delay in getting the bike, likely Christmas rather than summer, as I really don't have that amount of cash available just yet.

The bike doesn't need to go for 30/40/50 miles. 10 would be sufficient IF it can harness the battery in such a way, that it can essentially flatten out a 20% incline.

I would like to buy one From a store (as this allows for the BTWS) however again, I'm totally flexible if store bought ones will not suffice.

I have seen the Carerra Vulcan E from Halfords and the GTech adverts. Both look interesting, in budget, appear to do what I want, and are both on the BTWS.

However, before I go ahead and just buy one, it seems many if you here are very clued up on this. Motors, throttles, battery's, manufactures etc and I was hoping to utilise that knowledge so assist in getting me the right bike for me.

If the halfords bike will get me up the incline, I'm in, and I can pick one up this weekend. If not, but the GTech will, I can have one delivered by the weekend too. If none of these are suitable, then I am excited to look over new bikes that could achieve what I want to achieve.

I understand the guy who said get a moped. However, this really won't help me moving forward. I want to be mobile again, feel less like a prisoner than I do now, but at the same time, hear the birds, smell the sea air, enjoy the silence and improve my health at the same time.

It's taken a lot to get me to where I am now, it's been depressing, lonely and I've isolated myself almost entirely. Now, understanding that my situation isn't getting any better, I want to reconnect before it's to late, and perhaps extend what I may have previously wanted to end.

I dream that an elect bike can do that!

Last night I fell asleep with thoughts in my head of cycling down to the harbour and the beach near by.

Saying "HI" to old familiar faces, grabbing a sandwich and sitting on the pier listening to the waves crashing against the bantry wall. Then cycling around, the villages nodding and smiling at faces I used to know... Reconnecting, slowly in the hope I haven't left it to late.

It sounds boring, sad, and pathetic... I know. But to me, it really is the squeal to a book, that I genuine thought I wanted to end.

Maybe an electric bike can't do what I need it to do, but I'm reaching out for advice from anyone who knows. Maybe this weekend, I can do what I dreamt about last night and make the sequel better than the original

Somehow I had managed to miss this post amongst the others, but after having read it, it did make me smile for all the right reasons.

Sadly no longer with us, but not through/because of health related reasons, the following guy was very inspirational.

Svengailie or "The One Lung Warrior" always amazed me with what he could do, and whilst I never met him, we did correspond frequently, and he invited me out for ride with him, but circumstances sadly prevented this from ever happening.
Clearly his health issues were very different from that of your own, but if you need someone to ever give you boost, he would be a good person to take from. I'm certain sure that by buying an ebike, that you will suddenly have new horizons open for you.

This one very off topic YT clip of him is filmed on my own doorstep, and even on the eMTB, I have never been able to ride it*. In part, it was Svengailie's enthusiasm that got me involved with eMTB's in the first place. One of life's nice guys.

*The route has now been resurfaced and isn't worth looking at.

 

[anotherkiwi]

Getting back on subject:

I have been playing with https://www.doogal.co.uk/RouteElevation.php This is my typical ride to the city:

Start altitude: 6 metres
End altitude: 6 metres
Maximum altitude: 134 metres
Minimum altitude: 1 metres
Distance: 68.2 km <- why I needed a 720 Ah - 100 km battery
Total ascent: 808 metres <- 2650 ft
Total descent: 808 metres
Maximum gradient ascending: 13% at 46.6 km
Maximum gradient descending: 13% at 10.9 km

Now I know this ride quite well and for me it has some quite steep bits as you can see above. In fact along the way if you go off the Google path you can find bits which have a gradient of up to 40% i.e. steeper than Baldwin St. a.k.a. EddiePJ territory. I guess the Basques don't know about this Guinness world record... That is enough to stall any mid-drive trekking bike but you should be able to climb those bits very slowly on a hub drive e-MTB in say 28:42

 

[topographer]

Getting back on subject:

I have been playing with https://www.doogal.co.uk/RouteElevation.php

I was playing with it as well and having fun but then I tried it on Robin Hood's Bay and the gradient didn't seem right from personal experience. It said the hill was about 12% if I remember rightly but when I googled I found a pic of the hilltop with a 30% road sign (which does fit my memories of the hill). So I wonder how accurate that web tool is.

 

[Deleted member 4366]

Yes, that Google gradient isn't right. It shows a road where I go from zero to 43 mph in about 50 meters as 13% down and an alternative easy route I take to avoid that, coming the other way, as 15% up!

 

[topographer]

Yes, that Google gradient isn't right. It shows a road where I go from zero to 43 mph in about 50 meters as 13% down and an alternative easy route I take to avoid that, coming the other way, as 15% up!

Do you have to change your kecks when you get to the bottom of that?

 

[Deleted member 4366]

See for yourself. The steep drop is the bit before the house on the right:

 

[topographer]

See for yourself. The steep drop is the bit before the house on the right:

Doesn't look too mental but I know videos give a deceptive view of gradients.

 

[Deleted member 4366]

Yes, the video is a bit deceiving. When you take the first bend, you're right on the edge of grip, and if you get it wrong, there's that massive tree right in front of you. it's after that that you pick up speed rapidly and then drop down just before the house. During that bit, you have to look over the hedge to see that no cars are coming because normally I have to use the whole road to get round that bend at the bottom. once round that, you can relax and freewheel for the next mile at speeds between 20 and 30 mph.

The worst thing is cars that stop suddenly in front of you when one comes the other way or meeting one coming the other way when you take that first bend.

 

[jarob10]

And in real life the Bafang BBS02B 36V 250W trumps the lot hands down
Just saying.

Sent from my E5823 using Tapatalk

For completion, here's the power curve for the bbs01, taken from endless sphere

 

[brightonebikes]

For completion, here's the power curve for the bbs01, taken from endless sphere

that says bbs01...

Sent from my E5823 using Tapatalk

 

[Zlatan]

For completion, here's the power curve for the bbs01, taken from endless sphere

What does the second B stand for ???