Moving Away From Heavy E-Bikes

just looked at some articles where people drilled them themselves, and the weight went from 1167 to 936g per rim; that’s 231g per rim, which is pretty amazing lol, over a pound of aluminum rotating mass far from the hub. sure, not that much on a 40lb bike but it looks interesting too.
Maybe the point is to improve responsiveness in acceleration and braking by partially offsetting the HUGE rotational inertias in those giant tires. Question is, would 231 g per rim make a noticeable difference in the saddle?
 
How so? Better brakes or denying the laws of physics?
Heavier vehicles on the flat or going uphill, or where significant drag is involved (e.g. gravel) will indeed slow down more rapidly once power is removed vs lighter bikes. Same applies to wider tires in many cases etc.

Downhill and under equivalent braking power (on a flat smooth surface) is of course a different scenario…
 
Heavier vehicles on the flat or going uphill, or where significant drag is involved (e.g. gravel) will indeed slow down more rapidly once power is removed vs lighter bikes. Same applies to wider tires in many cases etc.

Downhill and under equivalent braking power (on a flat smooth surface) is of course a different scenario…

uhhh, no. a heavier vehicle going UPHILL will slow down faster. a heavier vehicle on FLAT ground may not. the forces acting to slow the vehicle down are all frictional, either aero drag, wheel/axle friction, friction between the wheel and the road, etc. the aerodynamic portion is likely far larger for a bike, which actually means the heavier bike will slow down less rapidly. the inertia of a heavy but same-shape object is much greater than a lighter object.
 
As an experiment, I modified the settings on my Ride1UP Roadster SS e-bike so that my EggRider display controller has the “Eco” PAS range set to the EU 25kph (15.5mph) max assist speed, and the “Sport” PAS range set to 45kph (28 mph) max assist speed.

A surprise to me, the 15.5 mph limited assist still worked out fine, and is a great setting when trying to hypermile with only the internal 250 wh battery and keeping the e-bike weight down to ~ 35 lbs (not using external battery, and not carrying a spare battery, which pushes it to ~42 lbs). I can still accelerate up to 25+ mph on the flats with my own power, but keep power consumption down to 2-4 wh/mile depending on terrain. And a lightweight bike is different experience, that I much prefer.

Found a non-profit place to donate my 50 lb geared e-bike that’s been sitting unused the past few years, so going to finally do that!
Actually, that’s something I’d be perfectly fine with and wouldn’t mind seeing - user-settable max speed settings. Some of the ‘configurable’ bikes/motor systems have the ability to set max current/power, I think a couple have the ability to set a max speed (by the user, not hard-coded/set by mfgr or dealer only). It’s not like most ‘e-bikes’ (those remotely meeting the general naming, vs electric motorcycles/scooters, etc.) aren’t exactly doing 50-60mph top speeds ‘unlimited’. This is also one of the reasons I ride most of the time in PAS 2 of 9 - for the range, as well as wanting some level of workout, yet if I want to work for it, I can eventually reach the realistic top speed imposed by gearing and RPM, which in the case of my X2, is somewhere around 30MPH /-.

Go on a greenway or trail system with posted limits, sure, I’d be fine pressing a button to limit my speed to ….for the duration of that ride. Certainly people can also do this themselves just like auto drivers do - I’d probably set it if I were able to do so, as really, there’s not much point in looking down at handlebars while riding. Back on the road for the ride home, clear the limit and ride responsibility. Unless of course you’re one of the ones claiming to represent the entirety of US riders and think we should all be limited to 15MPH or some such nonsense. ;)
 
uhhh, no. a heavier vehicle going UPHILL will slow down faster. a heavier vehicle on FLAT ground may not. the forces acting to slow the vehicle down are all frictional, either aero drag, wheel/axle friction, friction between the wheel and the road, etc. the aerodynamic portion is likely far larger for a bike, which actually means the heavier bike will slow down less rapidly. the inertia of a heavy but same-shape object is much greater than a lighter object.
I’m aware we could nitpick and have fun on this one endlessly.
You’re right on the flat surfaces, am just now having my morning coffee, sooo very sorry.. ;) More inertia once moving as stated, so indeed on a flat with all else being equal, the heavier bike will maintain momentum longe….

Real-world can vary without breaking any laws though - often enough the heavier bikes also have wider tires which will induce more drag.
Doesn’t make a huge amount of difference overall to the discussion though, more an aside. For some ‘fun’ we could always argue whether tire compound or brake pads on cars have a large impact on ability to stop…
 
I’m aware we could nitpick and have fun on this one endlessly.
You’re right on the flat surfaces, am just now having my morning coffee, sooo very sorry.. ;) More inertia once moving as stated, so indeed on a flat with all else being equal, the heavier bike will maintain momentum longe….

Real-world can vary without breaking any laws though - often enough the heavier bikes also have wider tires which will induce more drag.
Doesn’t make a huge amount of difference overall to the discussion though, more an aside. For some ‘fun’ we could always argue whether tire compound or brake pads on cars have a large impact on ability to stop…

yep, obviously weight related matters are much more noticeable going up or down hill in the real world. at >15mph aero really trumps weight on the flat either speeding up or slowing down!
 
yep, obviously weight related matters are much more noticeable going up or down hill in the real world. at >15mph aero really trumps weight on the flat either speeding up or slowing down!
It's even worse than that for most ebike riders. On a 65 lb commuter bike with an upright 200 lb rider in street clothing, the crossover ground speed Vc at which air resistance becomes 50% of total resistance is only 9 mph on the flat in still air.

Add a 10 mph headwind, and Vc = 0 mph. Add a 5% grade instead, and Vc jumps to 28 mph. Add both the grade and headwind, and Vc = 18 mph. However, few ebikes will ever reach the last two Vc values under said conditions.

These Vc trends mean that the combined weight-dependent resistance (slope + rolling) can easily dominate total resistance on even moderate grades. If shaving grams off an ebike ever makes sense at steady speed, that would be the time.

But all of the above assumes steady ground speed. Every gram counts during acceleration and braking, especially on the tires and rims. Aggressive weight reduction makes some sense when you're mainly after responsiveness.
 
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It's even worse than that for most ebike riders. On a 65 lb commuter bike with an upright 200 lb rider in street clothing, the crossover ground speed Vc at which air resistance becomes 50% of total resistance is only 9 mph on the flat in still air.

Add a 10 mph headwind, and Vc = 0 mph. Add a 5% grade instead, and Vc jumps to 28 mph. Add both the grade and headwind, and Vc = 18 mph. However, few ebikes will ever reach the last two Vc values under these conditions.

These Vc trends mean that the combined weight-dependent resistance (slope + rolling) can easily dominate total resistance on even moderate grades. If shaving grams off an ebike ever makes sense at steady speed, that would be the time.

But all of the above assumes steady ground speed. Every gram counts during acceleration and braking, especially on the tires and rims. Aggressive weight reduction makes some sense when you're mainly after responsiveness.
It's a miracle we manage to ride at all 🤣🤣
 
I recently purchased a second hand Smart e-bike (built by Daimler and BionX) - it has 350W of assistance and up to 100km range, and it has regenerative braking. It is a 60lb bike. BMW branded one was lighter at 40lb, there is one on ebay

 
Just show me your Strava profile.
Indeed, people recording on Strava are more credible because they can prove they have gathered necessary experience.
Tell that to this guy!
They used to call him 50,000 mile a year Freddie!


a bit more here

 
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Tell that to this guy!
They used to call him 50,000 mile a year Freddie!


a bit more here

Yes Marquez but this guy is not an EBR Forum member and I do not think he rides e-bikes :)
I would love having Arnold Schwarzenegger as a Forum member here, as he is indeed an e-biker. I would ask him why he rides Chinese cr*p, and would encourage him to wear the helmet :)
 
Arnold Schwarzenegger
He does ride electric bikes but was also known as the cigar smoking Hummer Guy. Our former Governor is not really a cyclist, he is more into Harleys. He could be on EBR, using a different name, such as @Armando55, or whatever. I like Acoustic, Acoustic-Electric, & Electric. He is also a moral force in the Republican Party.
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He does ride electric bikes but was also known as the cigar smoking Hummer Guy. Our former Governor is not really a cyclist, he is more into Harleys. He could be on EBR, using a different name, such as @Armando55, or whatever. I like Acoustic, Acoustic-Electric, & Electric. He is also a moral force in the Republican Party.
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I've just watched the "Arnold" documentary on Netflix.
He has been shown to ride an e-bike for several times, and he drove a big utility car only once.
 
I would like to make the custom bikes of the LA stars. For now it is only local. They don't know what they are missing.
 
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