I like that my e-bike is heavy...

[swbluto]

With all the weight in the rear with the hub and batteries, I can stop as fast as I want without endo-ing.


(Endoing was the cause of a significant childhood crash that I had. Scabs on your face near the mouth freakin' hurt!)

 

[gwhy!]

With all the weight in the rear with the hub and batteries, I can stop as fast as I want without endo-ing.


(Endoing was the cause of a significant childhood crash that I had. Scabs on your face near the mouth freakin' hurt!)

But all the stopping power is on the front, just having a heavier bike means it takes longer to stop.

 

[swbluto]

With all the weight in the rear with the hub and batteries, I can stop as fast as I want without endo-ing.


(Endoing was the cause of a significant childhood crash that I had. Scabs on your face near the mouth freakin' hurt!)

But all the stopping power is on the front, just having a heavier bike means it takes longer to stop.

Oh boy, a 10% increase in weight is going to kill me. (Although, it might. hehe.)

 

[AussieJester]

With all the weight in the rear with the hub and batteries, I can stop as fast as I want without endo-ing.


(Endoing was the cause of a significant childhood crash that I had. Scabs on your face near the mouth freakin' hurt!)

But all the stopping power is on the front, just having a heavier bike means it takes longer to stop.

I have the same thing with my cruiser but not because of a overweight frock motor hanging out the rear no no no SiR :lol:
its due to my BEEF CAKE self being situated very close to the rear wheel, the Avid Juicy 7 hydraulic brakes on the rear work
on a 6in disk and pull the bike up as fast as the Avids running on a 8in rotor up front... Result is some seriously good stopping
for a 45 kilo bike plus my 85kg aaaand the wheelchair in tow.

KiM

 

[torker]

70 % of your stopping is supposed to be up front. But in a car with an engine up front, right.? I can see it being different for a bike with 80% rear weight bias.

 

[dumbass]

The problem with a heavy tail is control in an emergency. I have 4 ebikes and 2 of them are Currie Ezips. One has extream mods. and the ass of that bike is way over weight and makes the front tire slipery in an emergency manuever. If I could I would relocate the lifepo4 packs (30 lbs) further forward. But there's just no room.

 

[AussieJester]

I can see it being different for a bike with 80% rear weight bias.

Old school choppers with long forks do without front brakes also, locking front wheels on the long forks would
do little to help stopping

KiM

 

[GrayKard]

With all the weight in the rear with the hub and batteries, I can stop as fast as I want without endo-ing.

I'm going with a heavier build for my second bike for the same reason. I want to get an even weight distribution though from front to back.

Doing stoppies and low speed endos because some idiot cuts me off is getting old.

Gary

 

[spinningmagnets]

I believe that when brakes are applied firmly, some of the bikes weight is shifted forward (depending on geometry and many other factors), so...I would imagine that a bike with roughly a 60% weight bias to the rear would be close to a 50/50% under braking load?

With the added braking power of discs, I am certain the biggest factor of concern then would be the small rubber tire patch that is in contact with the road. I believe spreading the braking load evenly over the two (or three) tires would give the shortest braking distance. If the rear tire is locking up and skidding, you not only have less control, you are also not getting as much braking power because the rear disc/rim-pads are not converting forward energy into heat.

And once the rear locks up and skids, additional bike weight inertia would all be transferred to the front brake/tire. Just my take on the subject....

Getting an even load on all tires under acceleration would be a different equation I think. (for extreme cornering?)

 

[John in CR]

Locking the rear up is a whole lot better than locking the front up, or any loss of traction on the front for that matter. Apparently hear easements are unheard of. They just finished cutting our street lengthwise for running a new water pipeline, and didn't bother to repair the road. Now the most dangerous part of my ride moved outside of our gate to the 150m of our street. Small rocks almost like a very coarse sand now covers our asphalt street. Not only do I approach the stop sign quite slowly, but I also use 70-100% rear brake to stop.

 

[swbluto]

Don't get me wrong. Dirt/trail riding would be much better with a lighter bike so an RC would be ideal there (If you lock the front brake, you're not going to endo... I think, since the dirt is "slippery"), but a hub seems to suit street-riding just fine. RC has better performance potential than hubs, true, but for commuting, the quietness, stealth and anti-endoing affect of a hub seems quite ideal. I'm also riding a "large" bike so that might have something to do with it.

I'd also bring up "reliability" but I haven't had a reliable hub yet. I'm hoping that my new 9C will prove more reliable than the older crystalytes.

 

[ElectricEd]

My big brudda used to race a Yammy TZ700 in the late 70s. When he was having a rest while training he'd let me have a few laps around Calder racetrack. I learned pretty quick that when braking heavily coming into Repco corner at the bottom of the straight you had to keep both wheels squirming and wimpering just before breakaway or you'd run off. The brake markers on the track side go past so fast that you pass one or two between thinking about braking and actually applying them. You are thrown into a 2-3G handstand on the handlebars with your crotch rammed against the rear of the tank, the chain rattling and snatching and the rear wheel is locking each time you put a bit too much pressure on the front brake. The chin of your helmet is rattling on the tank and you have blurred vision in a vertical plane. This is while the wind is roaring past as you try to get from about 300Kmh to just under 100Kmh so that you can crank it over to get around Repco. Even at this speed in the several acres of Repco's bitumen, the only line you that you know you can take must deviate less than 50mm or you'll be off.
The whole thing with severe braking is that you must use as much as possible on each wheel without losing traction. It takes a bit of practice, but it really pays when you need it. Locking up is an absolute no-no.

 

[amberwolf]

FWIW, on the long CrazyBike2, not having a rear brake makes a huge difference to being able to stop quickly; when I have one it is much easier. Usually I don't, though, since many rear wheel changes and breakages leave the brakes inoperable for one reason or another.

On DayGlo Avenger, similar problems occur, but I do usually have rear brakes working. Those in combination with the front give good stopping power, but as heavy as the bike is overall (with at least 75% rear bias even with the very heavy 9C front hub), it's still hard to get enough stopping power. Due partly to road conditions and partly to the cheap rims/spokes I have vs the weight they must carry, I rarely can keep a wheel true enough for more than a couple of rides, so I no longer bother adjusting the brakes to tight enough to let me lockup a wheel.

On both bikes, the front suspension reaction to braking is to compress, transferring significant weight to the front, and changing the steering angle a little. It appears to make the front brake more effective if I first brake the rear a little and then the front, but i could not say how much more. Noticeably, anyway. Due to the weight on the back, I don't feel any lessening of rear braking when this happens.

On my unsuspended Schwinn Sierra, even with bags of groceries strapped to a rear rack and on the sides, perhaps 40-50lbs of stuff, the rear and front rim brakes appear about equal in stopping power, and since there is no front suspension there does not appear to be as much of a weight-transfer to the front wheel happening. At least, it does not feel like there is. It's still a much lighter bike overall, though, by as much as 25-30lbs, as it has no motor/etc on it.

 

[Toorbough ULL-Zeveigh]

a hub seems to suit street-riding just fine. RC has better performance potential than hubs, true, but for commuting, the quietness, stealth and anti-endoing affect of a hub seems quite ideal.

if ur not being disingenuous as the left-handed praise of this thread's title would suggest then that's quite the 180º from i don't like hub motors.
you've neatly encapsulated what the hub crowd has been saying all along.
that a ferrari isn't needed or wanted all the time or even most of the time.
if i ever assemble a performance bike i'll use whatever is deemed appropriate for the application, if that means an rc setup then so be it.
i don't see the need for enemy camps & the 'if ur not with us ur against us' mentality at all, i prefer having the choice of many tools in the toolkit.

anyway as far as avoiding endos i think ur in for a treat & will wonder how u ever lived without it when u experience ebrake/regen for the first time (another advantage of a direct drive motor), properly dialed in it's almost like ABS.
it's the better way of getting the controlled braking ur looking for rather than the added heavy weight which i could definitely live without but unfortunately comes as part of the package (for the time being).

u really ought to do urself the favour, find an E+ dealer in ur area to take a test drive just to get some idea what a good quality hubmotor is like (not to mention reliable).
i believe the difference isn't all that vast but until i make my own rc unit can't really say for sur & would like hear what ur impression is then.

 

[swbluto]

if ur not being disingenuous as the left-handed praise of this thread's title would suggest then that's quite the 180º from i don't like hub motors.

I still don't like crappy hub motors, like the crystalyte I have. But it appears hub motors have recently improved (Mainly thanks to 9C) and their performance characteristics have improved as well to allow me to achieve the dream I originally had with e-bikes. So, it seems that they're becoming more acceptable.

 

[John in CR]

Why do you say your X4 is crappy?

 

[John in CR]

I rarely can keep a wheel true enough for more than a couple of rides, so I no longer bother adjusting the brakes to tight enough to let me lockup a wheel.

We need to help you get some small motorcycle wheels, or at least moped wheels. Guess how many times I've had to true mine...you got it, never.

 

[GrayKard]

Don't get me wrong. Dirt/trail riding would be much better with a lighter bike so an RC would be ideal there (If you lock the front brake, you're not going to endo... I think, since the dirt is "slippery"), but a hub seems to suit street-riding just fine. RC has better performance potential than hubs, true, but for commuting, the quietness, stealth and anti-endoing affect of a hub seems quite ideal. I'm also riding a "large" bike so that might have something to do with it.

I'd also bring up "reliability" but I haven't had a reliable hub yet. I'm hoping that my new 9C will prove more reliable than the older crystalytes.

I'm gonna throw a little gas on the fire here. IMO a properly set up off road bike with hub motors will do as good or better than an RC bike.

Why? Because it's pretty easy to do a 2 wheel drive DH bike with hubs. It would be very difficult to do the same with an RC setup. Sure there would be lots of times the rear wheel drive RC would blow the hub bike away. But when it really gets tough having twice the traction is going to make a big difference.

The other day I took a short cut next to some train tracks. The gravel is large and very loose. I'm sure I would not have been able to peddle through it. I doubt a rear wheel drive bike could hack it as the front wheel would plow when you tried to turn. A front wheel drive should do OK. But I had the biggest EV grin yet tearing through it on the Ibex.

Hmm, tonight I think I'll try the Mongoose on the same section and see how it does. I may be wrong and the big front tire might float and do fine.

Gary

 

[swbluto]

I'm gonna throw a little gas on the fire here. IMO a properly set up off road bike with hub motors will do as good or better than an RC bike.

It's possible, but I have to admit a light bike is more fun and responsive to handle - a light scooter, anyways, it substantially more fun to handle than a heavy one, so I'd imagine the same would be true of a bike even though probably less in degree. Plus, you can get as high as wheel torque as you want with an RC bike. But, it might not have much difference if you have oodles of torque if it only means your wheel is spinning in the dirt.

 

[liveforphysics]

But when it really gets tough having twice the traction is going to make a big difference.

You only need enough traction on the rear tire to enable it to raise the front, and at that point, powering the front wheel provides nothing but a weight penalty.

 

[GrayKard]

But when it really gets tough having twice the traction is going to make a big difference.

You only need enough traction on the rear tire to enable it to raise the front, and at that point, powering the front wheel provides nothing but a weight penalty.

If you can sustain a wheelie everywhere you go I guess you're right. Maybe an off road Unicycle would be best.

Gary

 

[AussieJester]

You only need enough traction on the rear tire to enable it to raise the front, and at that point, powering the front
wheel provides nothing but a weight penalty.

Exactly...motorcycle manufactures have dabbled with two wheel drives on moto-x bikes Yamaha ~2002-3 had
some WRF450 2x2 KTM also entered the party with a 2WD equipped KTM EXC 525 As far as i know none have
ever gone into full production. Although, IIRC Yamaha or Suzuki did put out a agriculture bike with two wheel
drive for a spell there for use on farms etc, in the mid 90's... but as Luke said its pointless on a motorbike when
all the traction is gained through the rear wheel under hard acceleration. I guess a novice rider crawling through sand
would benefit from a 2x2 but would soon out grow the usefulness of it once their skill level increased.

KiM

 

[liveforphysics]

But when it really gets tough having twice the traction is going to make a big difference.

You only need enough traction on the rear tire to enable it to raise the front, and at that point, powering the front wheel provides nothing but a weight penalty.

If you can sustain a wheelie everywhere you go I guess you're right. Maybe an off road Unicycle would be best.

Gary

They make a sport of that.

I'm pretty sold on RWD and proper tire choice is able to provide every bit of traction I could ever need.
[youtube]JbtZ2wnE7nQ[/youtube]

[youtube]AsXi3mLMYGI[/youtube]

 

[GrayKard]

You only need enough traction on the rear tire to enable it to raise the front, and at that point, powering the front
wheel provides nothing but a weight penalty.

Exactly...motorcycle manufactures have dabbled with two wheel drives on moto-x bikes Yamaha ~2002-3 had
some WRF450 2x2 KTM also entered the party with a 2WD equipped KTM EXC 525 As far as i know none have
ever gone into full production. Although, IIRC Yamaha or Suzuki did put out a agriculture bike with two wheel
drive for a spell there for use on farms etc, in the mid 90's... but as Luke said its pointless on a motorbike when
all the traction is gained through the rear wheel under hard acceleration. I guess a novice rider crawling through sand
would benefit from a 2x2 but would soon out grow the usefulness of it once their skill level increased.

KiM

Driving the front wheel of an ICE bike isn't too easy either. I think that is the problem with making a production version rather then it being low or zero benefit.

Gary

 

[AussieJester]

Driving the front wheel of an ICE bike isn't too easy either. I think that is the problem with making a production version rather then it being low or zero benefit.

Gary

No issue at all flexi shaft was used direct to the hub, the issue is it was pointless for the average rider & totally
pointless for experienced riders. i.e The types that would buy the type of bikes that were in 2x2 format.

kiM