Moving Away From Heavy E-Bikes

[Mike TowpathTraveler]

Thanks! Looks like a fun bike. The white tape was a good choice. Surprised tubeless works at all with those rims.

Ballpark, how much net wheel weight do the rim cutouts save, taking into account any weight added by the rim tape?

The white rim tape was/is OEM Specialized. They even took the time and effort to emboss the "Specialized" logo all over it. It's too bad they didn't invest in better rear hubs as well as a better pressed-in crankset; both things plagued many Fatboys of the first generation (I guess I was one of the lucky ones who has had problems with neither).

I never tried tubeless on that bike as I've read other owner's experiences with this rim & tubeless was not too successful. Too many leaks. I've found the fit between the tire bead and the rim is not as tight as on the H-Bike rims.

Honestly have no idea what kind of weight savings is gained by those holes. I think it's kind of silly for a bike mfgr to be concerned about saving a few ounces of aluminum on a bike that can run anywhere from 40 to 60 plus pounds!

 

[Gionnirocket]

The white rim tape was/is OEM Specialized. They even took the time and effort to emboss the "Specialized" logo all over it. It's too bad they didn't invest in better rear hubs as well as a better pressed-in crankset; both things plagued many Fatboys of the first generation (I guess I was one of the lucky ones who has had problems with neither).

I never tried tubeless on that bike as I've read other owner's experiences with this rim & tubeless was not too successful. Too many leaks. I've found the fit between the tire bead and the rim is not as tight as on the H-Bike rims.

Honestly have no idea what kind of weight savings is gained by those holes. I think it's kind of silly for a bike mfgr to be concerned about saving a few ounces of aluminum on a bike that can run anywhere from 40 to 60 plus pounds!

Well in addition to the weight there's also the material savings for the manufacturer. That's a lot of savings in aluminum which help keep cost down without sacrificing strength.
Then there's the environmental impact when using less..

 

[PSm]

Well just as we have different speed limits in different parts of any city /state... Do so with ebikes. That doesn't mean that you need to restrict the ebike. My car can easily do 140mph...but I don't, especially when in Manhattan

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!

 

[mschwett]

…
Honestly have no idea what kind of weight savings is gained by those holes. I think it's kind of silly for a bike mfgr to be concerned about saving a few ounces of aluminum on a bike that can run anywhere from 40 to 60 plus pounds!

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.

 

[Gionnirocket]

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!

That's great... Many times less is more.
I'm just saying don't restrict those that less isn't enough for their needs.

 

[PSm]

That's great... Many times less is more.
I'm just saying don't restrict those that less isn't enough for their needs.

% agree. Having the option to use available higher assist and speeds when I want is

 

[Jeremy McCreary]

Honestly have no idea what kind of weight savings is gained by those holes. I think it's kind of silly for a bike mfgr to be concerned about saving a few ounces of aluminum on a bike that can run anywhere from 40 to 60 plus pounds!

Looks kinda silly to me, too. Hard to imagine a noticeable reduction in the weight-dependent resistances (slope and rolling) in a bike this heavy. And with no suspension, unsprung weight isn't a consideration.

Maybe the point is to improve responsiveness in acceleration and braking by partially offsetting the HUGE rotational inertias in those giant tires. But even there, hard to imagine the rim cutouts making a noticeable difference.

 

[rtp]

you mean in your part of the US - and/or in your opinion!

Yep in many parts of the US and indeed in my opinion. A speed limit is at least more sense than arbitrary nominal power.

the majority of people who actually commute with e-bikes in the united states are in a handful of densely populated cities - seattle, portland, san francisco, new york, etc. 20mph on the bike infrastructure there is a very reasonable compromise to allow e-bikes full access.

the united states is a large and diverse country, and different places need different rules. but make no mistake - most people riding bikes are in the big cities. nationally something like a half a percent commute on bikes, but there are census tracts around here where that number is 20 or 30 times that!

I’ve ridden motorcycles through NYC and good portions of the country as well as overseas and off-road. For a while, I really liked the Suzuki DRZ-400S, as it was light, had good suspension travel for real off-road, and was overall a fun bike. Of course, everything is a compromise - the lighter the bike (or car… tend to drive light vehicles with some power), the more impacted by wind or trucks passing you on the road. It had another issue in that it was top-speed/top-end limited by it’s lack of a 6th gear (or changing it’s top gearing), which occasionally became a real issue when at times, you NEED a burst of speed to actually avoid problems/careless drivers, etc.

So no, I don’t believe in the artificial forced limit of top speed being mechanically/electrically enforced, and no, I don’t agree that 20mph should be that limit in the US. That is different, however, versus being entirely fine if some specific areas (not the entire bike) have posted speed limits. I have no issue n trails for example being posted as 15mph speed limit, but when then going onto roads, which for much of the US ‘bike infrastructure’ is a sad joke, I’ll follow the posted speed limits but don’t expect to have the bike force me to some arbitrary reduced limit, etc.

 

[Jeremy McCreary]

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?

 

[rtp]

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…

 

[mschwett]

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.

 

[rtp]

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.

 

[rtp]

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…

 

[mschwett]

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!

 

[Jeremy McCreary]

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.

 

[Gionnirocket]

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

 

[Salle071]

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

BMW Active Hybrid E-Bike | eBay

Find many great new & used options and get the best deals for BMW Active Hybrid E-Bike at the best online prices at eBay! Free shipping for many products!

www.ebay.ca

 

[kevinmccune]

The whole point about the lead acid battery is it does not burn.

There is a another interesting fact about PbSO4 according to Sandy Munroe when they were doing work for the US military researching power storage, the lead acid battery when stressed and discharged very gently to a small percentage of its capacity had an almost indefinite life span, have seen the old "jar" batteries some phone companies use and have never heard of them being replaced.The old "Delco" plants( motor generator units popular before REA,) had a bank of 'jar' batteries they seemed to have a pretty good lifespan. The thing is power to weight, lithuim cells are much lighter OTH if I were to mortage my soul and go off grid I would use the so called "Immortal battery" NiFe the "Iron Edison cell.

 

[PedalUma]

!!!

 

[kevinmccune]

!!!

Wheres the "Fairy Dust"?( can I borrow that Unicorn?)