UK Legal Limit

[CyberCrime]

Out of all the UK legal limit bikes out there what would have the most powerful motor for pulling uphill?
I guess most if not all will hit the 15.5mph limit. But is the 250watt limit normal output or peak output?

 

[103Alex1]

Out of all the UK legal limit bikes out there what would have the most powerful motor for pulling uphill?
I guess most if not all will hit the 15.5mph limit. But is the 250watt limit normal output or peak output?

250W is nominal continuous output. If that was peak output you'd have trouble climbing anything of note. Most if not all will deliver more power - but critically not continuously. All restricted bikes tail off assist at 15mph or 1-2 mph more unless they're modded to assist at higher speeds - which of course means they're no longer within the "acceptable parameters".

BH E-motion NEO gets good reports on longer steep uphill assists. Never tried one personally. Some newer ones being tried out others will no doubt comment on in comparison to this.

It's high torque that gives you a more powerful climber but that's usually traded off against lower top speed. The latter's often pretty academic if the bike's speed-limited - so never understood why all 'legal' bikes aren't designed to be as torquey as possible given top speed is effectively irrelevant to all intents and purposes. Motor RPM speed likely not the limiting factor when you engineer a premature speed cutout below the motor's reasonable capabilities.

Impulse is great but only for limited distance climbs if you want to sustain higher speeds on very steep assisted ascents. There's an interesting and recent review on Impulse vs Bosch if you look on the Electric Bike Reviews section.

 

[Geebee]

A crank drive on steep hills.

 

[jackhandy]

Check out the Haibikes - preferably test-ride them....

Then work down the lists of 250w bikes, pricewise, until you find something that performs well enough for your needs, at a price you can afford

 

[JuicyBike]

To answer your question 250w is average/normal. Many peak at over 700

 

[andy slow coach]

Check out the Haibikes - preferably test-ride them....

Then work down the lists of 250w bikes, pricewise, until you find something that performs well enough for your needs, at a price you can afford

Second that!

On Thursday I rode out to a hill a few miles from where I live, I'm not sure of the exact distance, elevation, or time taken (will need to go back and do some more accurate measurements) but its signposted as 14% and I would say its about 1/2 mile long.
On the first assent my bike was in 'Tour' mode, I managed this hill with no problem and each time I glanced down at the speedo I was doing around 8.5mph.
I then rode down and did it again.
The second assent I turned the power off and rode unassisted to the top, it took longer and boy was I cream-crackered, this is the 1st time I have had to get out of the saddle since buying it! When I had a chance to glance at the speedo i was doing between 3.6 and 4.8mph.
At the top I decided to have a breather for about 10 minuets, then I went back down but this time peddled like mad and managed a top speed of 43.1mph.
The third time I went up I switched the bike to 'Turbo' and although each time I looked at the speedo I was doing around 9 mph I was certainly not putting anywhere near as much effort in.
I got to the top and continued to cycle home with no problems.

 

[Deleted member 4366]

Out of all the UK legal limit bikes out there what would have the most powerful motor for pulling uphill?
I guess most if not all will hit the 15.5mph limit. But is the 250watt limit normal output or peak output?

BH Emotion Neos have the most powerful motors. You only have to look at the size of their motors to see why they're the most powerful. The stator and rotor, which are the parts of the motor that give the power/torque, are twice the size of the crank-drive bikes. Crank-drive bikes can climb steep hills nearly as well by using less power but more torque because they can get the power through the gears.

Kudos have a couple of bikes with the same motor as the Neos, so they have the potential to be as powerful, but nobody's done a back-to-back comparison yet to confirm.

 

[shemozzle999]

Out of all the UK legal limit bikes out there what would have the most powerful motor for pulling uphill?
I guess most if not all will hit the 15.5mph limit. But is the 250watt limit normal output or peak output?

Your first problem will be to initially find a legal bike - before you can do a comparison.

 

[jackhandy]

Second that!

On Thursday I rode out to a hill a few miles from where I live, I'm not sure of the exact distance, elevation, or time taken (will need to go back and do some more accurate measurements) but its signposted as 14% and I would say its about 1/2 mile long.
On the first assent my bike was in 'Tour' mode, I managed this hill with no problem and each time I glanced down at the speedo I was doing around 8.5mph.
I then rode down and did it again.
The second assent I turned the power off and rode unassisted to the top, it took longer and boy was I cream-crackered, this is the 1st time I have had to get out of the saddle since buying it! When I had a chance to glance at the speedo i was doing between 3.6 and 4.8mph.
At the top I decided to have a breather for about 10 minuets, then I went back down but this time peddled like mad and managed a top speed of 43.1mph.
The third time I went up I switched the bike to 'Turbo' and although each time I looked at the speedo I was doing around 9 mph I was certainly not putting anywhere near as much effort in.
I got to the top and continued to cycle home with no problems.

The term "Glutton for punishment" springs to mind

Well done you: I don't suppose you have gps charts of your speed over the 3 runs, do you.

I'm looking for graphic illustrations of "What would an ebike do for me?", that's always asked by regular cyclists:

 

[andy slow coach]

The term "Glutton for punishment" springs to mind

Well done you: I don't suppose you have gps charts of your speed over the 3 runs, do you.

I'm looking for graphic illustrations of "What would an ebike do for me?", that's always asked by regular cyclists:

Jackhandy, I'm working on that, just using apps on my phone at the mo but not getting consistent results, and I did not start and stop the app for each run just started it from home and stopped it when I got back.

I will return and do some more specific tests. I did post a graph a while back when I first got my ebike comparing my commute to work with my MTB but the altitude graph did not match, tree cover I guess? Here.

 

[alban]

I can say that my Tonaro BigHit will climb most hills OK with little assistance (and I'm 110KGs) You can gear these crank-drive bikes to suit. By putting a smaller chainwheel (34t) or larger rear cogwheel (32t) on you can enable the bike to increase torque and climbing at the expense of top speed - but still do 12mph on the flat.
The Woosh CD bikes seem to be similar. Kits like GNG also. There's a lot of info on here about kits.
The trouble with crank drives is that you put strain on the whole gearing system so there's more to go wrong - eg a few have experienced gear box failure in the Tonaros (but it's reparable and probably due to putting more power through than standard). If you are going to be using it a lot then a hub is perhaps more reliable unless you buy the more expensive crank-drives.

 

[jackhandy]

Jackhandy, I'm working on that, just using apps on my phone at the mo but not getting consistent results, and I did not start and stop the app for each run just started it from home and stopped it when I got back.

I will return and do some more specific tests. I did post a graph a while back when fyI first got my ebike comparing my commute to work with my MTB but the altitude graph did not match, tree cover I guess? Here.

It'd be great if you're able to post some more graphs, Andy: Plenty of us log our rides, but not many do the comparison with a regular bike.

I reckon that kind of graphic comparison will sell more ebikes than all the bull spouted by some of the "experts" out there.