First E-Bike - Doing DIY BBSHD - Critique my plan

General Discussion about electric bicycles.
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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by Thomsontouring » May 03 2019 8:30am

The other thing common to scooters and mopeds is small diameter wheels. Large wheels on bicycles not only smooth out the ride by decreasing the contact angle of road imperfections, but they also contribute to stability. One of my motorcycles was a cruiser-style with 19" front rim and I could steer with one finger on the grips. Another one was a sport bike with 15" tires, and that one was twitchy as anything, especially below 40mph.
I also keep my e-bike seat adjusted on the low side which enhances stability and lowers wind resistance at the expense of pedaling efficiency. With 1000w of motor the legs don't contribute a whole lot anyway and pushing those pedals around for several hours at a time is certainly exercise.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by wturber » May 04 2019 12:50pm

furcifer wrote:
May 01 2019 5:15pm
wturber wrote:
May 01 2019 2:38pm
OK. The funny thing here is that the frame that broke was a Mongoose Impass - a full suspension bike. After riding both, the guy in the video strongly recommends the hardtail.
Dude, the Mongoose Impasse is a $400 FS bike. You know it's basically fake and possibly the worst possible choice for an ebike? It's heavier because of the suspension, but the suspension doesn't function so it's dead weight. I think even you and I can agree to avoid those bikes like the plague.
Dude. You were in such a rush to confirm your bias that you missed that it wasn't the hardtail that broke. That's the point. But the OP is past this non-issue so this is the last I'll post on it here.
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viewtopic.php?f=2&t=90369

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 04 2019 2:37pm

wturber wrote:
May 04 2019 12:50pm
Dude. You were in such a rush to confirm your bias that you missed that it wasn't the hardtail that broke. That's the point. But the OP is past this non-issue so this is the last I'll post on it here.
I never said it was the hardtail, I said it the crappy FS Mongoose. :?:

Yes, there are many more interesting threads in this forum. I'm reading one about a FS scooter. Yes, this crazy Russian guy wanted to go fast on a scooter so he designed a full suspension for it. Go figure! :mrgreen:

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by Chalo » May 04 2019 2:51pm

Tiny wheels need suspension even when they're not going very fast. That's why real bikes don't have tiny wheels, or even wheels as small in diameter as those on a motorcycle.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 04 2019 3:15pm

Thomsontouring wrote:
May 03 2019 8:30am
The other thing common to scooters and mopeds is small diameter wheels. Large wheels on bicycles not only smooth out the ride by decreasing the contact angle of road imperfections, but they also contribute to stability.
Not really. Mopeds have large wheels relative to their size (16" is most common). The front wheel on the Yamaha R1 is 2" smaller than the one on my moped! It's probably 4 or 5 times as wide though. It's common to find small wheels on scooters now. They have wider wheels for stability and much more suspension than the mopeds that proceeded them.

Large wheels don't smooth out the ride. Road bikes have the largest wheels and the worst ride of all bicycles. By a far, far margin.
Thomsontouring wrote:
May 03 2019 8:30am
One of my motorcycles was a cruiser-style with 19" front rim and I could steer with one finger on the grips. Another one was a sport bike with 15" tires, and that one was twitchy as anything, especially below 40mph.
I also keep my e-bike seat adjusted on the low side which enhances stability and lowers wind resistance at the expense of pedaling efficiency. With 1000w of motor the legs don't contribute a whole lot anyway and pushing those pedals around for several hours at a time is certainly exercise.
The cruiser had more suspension. Road bikes have less. The less the bike bounces the more control you have. It has little to do with wheel diameter. The width of the wheel plays more role than the diameter. The 15" wheels on the sport bike are to keep the center of mass lower.

Let's not confuse stability with suspension though. Stability is about center of mass, suspension is about vibration. The two aren't mutually exclusive, but they are different. There is something to be said for losing some stability with full suspension because typically it requires raising the center of mass. On an ebike the battery and motor are so much heavier they affect the center of mass significantly more than a change in ride height due to adding full suspension.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 04 2019 3:23pm

Chalo wrote:
May 04 2019 2:51pm
Tiny wheels need suspension even when they're not going very fast. That's why real bikes don't have tiny wheels, or even wheels as small in diameter as those on a motorcycle.
So that's why your 30 mph ebike has bigger wheels than a 200mph MotoGP? Because it's a real "bike"?

I have no clue what you're on about anymore. You're argument is so flawed it's requiring you to make outrageous statements like the on above. I don't know what "real" bikes are. Apparently you think your 10 speed is a real bike, but the Yamaha R1 isn't?

I'm talking about what's required to safely move a 2 wheeled vehicle at increasing velocities.

eta: plus suspension doesn't change the wheel size. I'm not sure how you got off on this tangent? I can address your misconceptions and failed attempts at understanding how dampening works, but you have to grasp the basics first.

Larger wheels are much more flexible, resulting in some dampening but increased instability. This should go without saying but if you need me to explain it I can.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by markz » May 04 2019 4:52pm

One thing to keep in mind is you can plan and plan and plan, and research and plan but the key to victory is to just get it done and ride!

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by wturber » May 04 2019 8:00pm

furcifer wrote:
May 04 2019 2:37pm
wturber wrote:
May 04 2019 12:50pm
Dude. You were in such a rush to confirm your bias that you missed that it wasn't the hardtail that broke. That's the point. But the OP is past this non-issue so this is the last I'll post on it here.
I never said it was the hardtail, I said it the crappy FS Mongoose. :?:
No. You didn't bring up that it was a Mongoose frame, I did. You said this, "I haven't finished watching the first one but he's already talked about breaking spokes, breaking one frame and bending a new one. " Pointing out that he broke a frame doesn't support your assertions if the broken frame happens to be a suspension frame. It is just another case of you failing to support you assertions.

One more example showing a non-suspension bike and its durability and fitness for purpose can be found in this thread. Warren is at 22,784 miles on his cargo recumbent.
https://endless-sphere.com/forums/viewt ... =3&t=78828

OK. Now seriously. This is my last post here on the suspension no-suspension non-issue.
"Commuter - DC Booster"
Iron Horse 3.0 hardtail - 48V / 1000W / 470rpm generic Chinese DD Hub motor (ebay)
8 x 36v 4.3ah 10s 2P battery packs - 1500W 30A DC Boost Converter delivers 54v and about 1000 watts peak
53T/42T Sakae Road cranks - 30mph+ on flats
viewtopic.php?f=2&t=90369

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 04 2019 8:10pm

markz wrote:
May 04 2019 4:52pm
One thing to keep in mind is you can plan and plan and plan, and research and plan but the key to victory is to just get it done and ride!
Well said.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 04 2019 8:12pm

wturber wrote:
May 04 2019 8:00pm
furcifer wrote:
May 04 2019 2:37pm
wturber wrote:
May 04 2019 12:50pm
Dude. You were in such a rush to confirm your bias that you missed that it wasn't the hardtail that broke. That's the point. But the OP is past this non-issue so this is the last I'll post on it here.
I never said it was the hardtail, I said it the crappy FS Mongoose. :?:
No. You didn't bring up that it was a Mongoose frame, I did. You said this, "I haven't finished watching the first one but he's already talked about breaking spokes, breaking one frame and bending a new one. " Pointing out that he broke a frame doesn't support your assertions if the broken frame happens to be a suspension frame. It is just another case of you failing to support you assertions.

One more example showing a non-suspension bike and its durability and fitness for purpose can be found in this thread. Warren is at 22,784 miles on his cargo recumbent.
https://endless-sphere.com/forums/viewt ... =3&t=78828

OK. Now seriously. This is my last post here on the suspension no-suspension non-issue.
I never said the first frame he broke was rigid. What you've quoted just proves that. Please stop putting words into my mouth.


Suspension is better for speed and weight. END OF STORY

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by markz » May 04 2019 10:21pm

It is not the end of the story.

For speed, shaving grams for a light weight bike seems to be a thing.
https://www.youtube.com/watch?v=dPn4RNvn4EE
If you noticed how the builder cut holes into the brake levers to shave weight.
He also sanded down the carbon fiber to get more grams shaved off.
He did everything possible to shave all the grams, anything you could think of, cf pulley gears, cf crank.
EVERYTHING!
Next look as his fashionable wears, he even drilled holes into his clothing, so shave even more grams. Also do not eat nor drink before the ride, and please take off the bottle holders.
AMAZING!

^But thats Lycra style, not a high percentage of roadies on E.S. I would ASSume.
Full suspension, Super Light (SL) like the Spark RC 900 SL at 7.86kg (17.33lb).
https://bikerumor.com/2018/03/27/bfs201 ... ark-scale/

:thumb: Idea: Perhaps start a new market niche, with carbon fiber torque arms, and very light, yet powerful motors.


Okay, so which is better? The answer is: it depends. It comes down to personal preference, riding style, average terrain encountered, and other factors.

Climbing, a rigid bike is good.

Downhill, a full suspension bike is good. But you can use your legs as the suspension on a rigid bike, but you'd get tired faster. Any kind of jumps, maybe your old or your really old then F.S. saves the nut sack massage.

Maintenance, yup more on a F.S.
Weight, yup more weight on a F.S.
Price, yup costs more on a F.S. you could just buy a used full suspension bicycle, but then you may want a stiffer/lighter coil spring.

With us ebikers, weight for some would be top pick. Maybe the single track riders, or the quick moves back and forth on a curvy path. People that have to walk up and down stairs with their bicycle.

Selection is another consideration, what is available on the used market, then compare that to the price you want to pay.

I do not see any couriers downtown riding F.S. and yet they pop curbs all the time. I would ASSume that most couriers are Lycra's at heart, or their maybe some fixie type old schoolers / hippies yes you know the type. Some peeps have certain kicks, like classic rods to show off on Fri + Sat nights or at the Show & Shine's. Same goes for bicyclers.

Analyze your requirements and select from there.

If I could find a fat bike that is full suspension, with a custom coil spring for cheap, I'd buy if its cheap enough. :lol:

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by Chalo » May 05 2019 12:41am

furcifer wrote:
May 04 2019 3:23pm
Chalo wrote:
May 04 2019 2:51pm
Tiny wheels need suspension even when they're not going very fast. That's why real bikes don't have tiny wheels, or even wheels as small in diameter as those on a motorcycle.
I don't know what "real" bikes are. Apparently you think your 10 speed is a real bike, but the Yamaha R1 isn't?
What part of the word "motorcycle" abbreviates to "bike"?

The Yamaha R1 is a motorcycle. That's not what we're talking about here.
eta: plus suspension doesn't change the wheel size. I'm not sure how you got off on this tangent? I can address your misconceptions and failed attempts at understanding how dampening works, but you have to grasp the basics first.

Larger wheels are much more flexible, resulting in some dampening but increased instability. This should go without saying but if you need me to explain it I can.
If you don't get the relationship between wheel size and ride quality, I can't help you. But performance bikes before the advent of pneumatic tires all had wheels of 54 inches and up. After pneumatic tires came around, wheels under 30 inches in diameter became common. That's where we're at now. Specialty bikes like Moulton use suspension to mitigate the ride quality hit you take by using even smaller wheels. That doesn't buy back the gap bridging or traction advantages of larger diameter wheels, though.

Wheels are not flexible in any significant way that contributes to suspension qualities. But I'm not surprised that you have that misconception.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 05 2019 10:26am

Chalo wrote:
May 05 2019 12:41am

What part of the word "motorcycle" abbreviates to "bike"?
"motorBIKE" "motorCYCLE"

So the last part.

You're trolling here right? Cuz this is pretty simple stuff.
Chalo wrote:
May 05 2019 12:41am
The Yamaha R1 is a motorcycle. That's not what we're talking about here.
We're talking about a cycle with a motor.

I say motor, you say cycle. "Motor"

Capiche?

Chalo wrote:
May 05 2019 12:41am
Wheels are not flexible in any significant way that contributes to suspension qualities. But I'm not surprised that you have that misconception.
Utter nonsense. I suggest you change your tire pressure and loosen your spokes if you think spoked wheels don't flex.

I'll explain this to you once. Spoked wheels flex significantly. That's their major advantage, they flex before they break. Mag wheels are lighter but less flexible and not as strong. This is why you see mags on Sport bikes and spoked wheels on motocross and some cruisers.

You don't understand the mechanical properties of wheels or suspension or you would understand these applications and why.

The problem with using the wheel as suspension is the forces aren't directed perpendicular to the plane of travel. Instead of up and down, like you would with a suspension fork and shocks, you get side to side motion. Side to side motion creates instability that increases with speed and load.

Road bikes are extremely unstable. This is why the internet is full of professional riders letting go of their bars prematurely to celebrate their victories and crashing feet from the finish line, massive pile ups because they can't avoid the rider ahead or ride over obstacles. Instead they fall like dominoes.

But you'd know this if you ever road one.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 05 2019 11:04am

markz wrote:
May 04 2019 10:21pm
It is not the end of the story.

For speed, shaving grams for a light weight bike seems to be a thing.
https://www.youtube.com/watch?v=dPn4RNvn4EE
If you noticed how the builder cut holes into the brake levers to shave weight.
He also sanded down the carbon fiber to get more grams shaved off.
He did everything possible to shave all the grams, anything you could think of, cf pulley gears, cf crank.
EVERYTHING!
Next look as his fashionable wears, he even drilled holes into his clothing, so shave even more grams. Also do not eat nor drink before the ride, and please take off the bottle holders.
AMAZING!

^But thats Lycra style, not a high percentage of roadies on E.S. I would ASSume.
Full suspension, Super Light (SL) like the Spark RC 900 SL at 7.86kg (17.33lb).
https://bikerumor.com/2018/03/27/bfs201 ... ark-scale/

:thumb: Idea: Perhaps start a new market niche, with carbon fiber torque arms, and very light, yet powerful motors.


Okay, so which is better? The answer is: it depends. It comes down to personal preference, riding style, average terrain encountered, and other factors.

Climbing, a rigid bike is good.

Downhill, a full suspension bike is good. But you can use your legs as the suspension on a rigid bike, but you'd get tired faster. Any kind of jumps, maybe your old or your really old then F.S. saves the nut sack massage.

Maintenance, yup more on a F.S.
Weight, yup more weight on a F.S.
Price, yup costs more on a F.S. you could just buy a used full suspension bicycle, but then you may want a stiffer/lighter coil spring.

With us ebikers, weight for some would be top pick. Maybe the single track riders, or the quick moves back and forth on a curvy path. People that have to walk up and down stairs with their bicycle.

Selection is another consideration, what is available on the used market, then compare that to the price you want to pay.

I do not see any couriers downtown riding F.S. and yet they pop curbs all the time. I would ASSume that most couriers are Lycra's at heart, or their maybe some fixie type old schoolers / hippies yes you know the type. Some peeps have certain kicks, like classic rods to show off on Fri + Sat nights or at the Show & Shine's. Same goes for bicyclers.

Analyze your requirements and select from there.

If I could find a fat bike that is full suspension, with a custom coil spring for cheap, I'd buy if its cheap enough. :lol:
I need to add one thing here.

Both kinetic energy and friction vary to the square of the velocity. Double the speed and you need to be 4 times as strong and deal with 4 times the wind resistance. Double the weight and you need to be 2 times as strong again.

That's just simple physics and you can't get around it. Frames tend to have a greater factor of safety built in than wheels, this is why ebikes break spokes.

You need to consider these scaling factors when building an ebike. Shaving weight at the cost of strength for instance, has diminishing returns as speed increases. You're dealing more with drag and offsets any additional weight from things like suspension.

And, no you can't use your body as a replacement for suspension. If you could kids on road bikes or XC would be killing it in downhill. You can lessen the effects but obviously there are limits and they have nothing to do with age or experience. They have to do with physics.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by Chalo » May 05 2019 11:50am

You're wrong about wheels (if you were right, they'd self-disassemble, and only poorly built wheels do that) and you're wrong about suspension. Probably 99% of the billions of bicycles in the world don't have it, for sound practical reasons. The small number that do, have it for jollies rather than practical reasons.

I'm done feeding this troll. Into the bozo box with you.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 05 2019 12:59pm

Chalo wrote:
May 05 2019 11:50am
You're wrong about wheels (if you were right, they'd self-disassemble, and only poorly built wheels do that) and you're wrong about suspension. Probably 99% of the billions of bicycles in the world don't have it, for sound practical reasons. The small number that do, have it for jollies rather than practical reasons.

I'm done feeding this troll. Into the bozo box with you.
Everything I've said is factually correct. So stop trolling and provide evidence. Your opinion is irrelevant (and wrong).

"Bicycles" in the general sense you are talking about don't need suspension because they are slow. Every single powered 2 wheeled vehicle, which is what I am talking about, does.

That's a fact. Your crusade to go the opposite way every single vehicle vehicle engineer in the world has gone over the last 100 years is not only dumb, but potentially dangerous.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 05 2019 1:14pm

To the OP

I just did a 8.7 mile ride in 30 minutes. Pretty much full throttle and on decent roads. I think your goal is doable but your chances of doing this 5 days a week 8 to 10 months a year is low. You're going to find its tough on good days and dreadful on bad. Not taking advantage of full suspension is going to make that harder.
I think you will find you're going to have to slow down to normal bicycle speeds, shoot for 1-1.25 hrs. or consider FS. Your not going to want to take the vibration for 45 minutes on a rigid frame.
It's OK on a nice Sunday ride but Monday mornings when it isn't you'll be looking for your car keys.

Best of luck. Report back with how it goes. Im curious with how well you fare.

eta: on the way back I found a slightly better route. and I had the wind at my back. there was little traffic so I could use the entire lane. I still hit a few of those patches that rattle the frame and can be felt in the posterior. I stopped along the way to visit but I still managed to average about 17mph for the trip while I was moving.
On a side note, I stopped at a red light and planned to make a left turn by walking my bike through the pedestrian crosswalk (sometimes it's just not safe to go from the right all the way over to the left turn lane). I stopped, got off my bike and onto the sidewalk, and then turned to walk across. The minivan coming up behind me in my lane blew through the red light, almost taking me out, the car entering the intersection and a kid crossing the street on the opposite side. The driver in the car that was entering the intersection stopped to ask me if I was OK.
This is just an example of how indirectly full suspension is the way to go. You can ride aggressively off the saddle and use your body as suspension, but all of that requires focus in front of you. The more you look forward the less you can look back, and the stuff approaching from behind is just as dangerous if not more dangerous than the road ahead.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by markz » May 05 2019 7:37pm

Lots of reports online about the pro's and con's of each.

Please leave the subject matter alone and move on to more meaningful information for the Original Poster (O.P.)

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 05 2019 9:22pm

markz wrote:
May 05 2019 7:37pm
Lots of reports online about the pro's and con's of each.
Lots of reports online about young horny girls in your area waiting to meet you. The chances you're getting laid tonight by horny teens in your area are the same as full suspension being a con. :mrgreen:

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by markz » May 05 2019 9:58pm

Well if your into immature teens with braces then your ready to go, just say Hello to Chris Hansen when you meet him on camera.


I prefer full suspension, it takes the bite out of the bumps!
If f.s. is so great, then the bicycle stores should be selling 100% f.s. and no rigids.


furcifer wrote:
May 05 2019 9:22pm
Lots of reports online about young horny girls in your area waiting to meet you. The chances you're getting laid tonight by horny teens in your area are the same as full suspension being a con. :mrgreen:

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by E-HP » May 06 2019 1:23pm

markz wrote:
May 05 2019 7:37pm
Lots of reports online about the pro's and con's of each.

Please leave the subject matter alone and move on to more meaningful information for the Original Poster (O.P.)
That would be nice. I've never seen a thread where the word "stupid" is used so frequently (based on the topic search tool), and directed so broadly. I hope the OP doesn't feel the need to choose sides. :shock:

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 07 2019 5:09pm

E-HP wrote:
May 06 2019 1:23pm
markz wrote:
May 05 2019 7:37pm
Lots of reports online about the pro's and con's of each.

Please leave the subject matter alone and move on to more meaningful information for the Original Poster (O.P.)
That would be nice. I've never seen a thread where the word "stupid" is used so frequently (based on the topic search tool), and directed so broadly. I hope the OP doesn't feel the need to choose sides. :shock:
I don't know what else to call the total disregard for safety and sound engineering practices.

It's one thing to say you prefer rigid because it's cheaper and easier to find, less maintenance etc. It's quite another to make up a bunch of nonsense in order to defend your preference.

Posters like Chalo don't know what they are talking about, and clearly don't have a grasp of the physics. This is dangerously ignorant. There are serious safety concerns to consider when you start moving at higher and higher speeds. This isn't an area of opinion, this is fact.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by Ribiero » May 07 2019 7:16pm

Off topic to the op and directed to Furcifer. At the point you chose to assemble a hard tail did you already have the knowledge and opinion you hold now? This is the part I cannot capiche. Why did you design something you understood wouldn't work. Could you tell us more about the components you used, specifically frame, forks, rims, hubs, tyres, tyre pressure, battery weight and position. Would you elaborate on how the frame is getting beat up, or the ride characteristics you find sub par. Finally could you give a short précis of your cycling experience.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by donn » May 07 2019 9:02pm

Arghh. To the OP - I'm never going to look at this thread again, and I suppose there are others with the same idea. If you want to return to a discussion of your ideas for a build, I recommend that you start a new thread. This one is shot.

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Re: First E-Bike - Doing DIY BBSHD - Critique my plan

Post by furcifer » May 08 2019 1:19am

Ribiero wrote:
May 07 2019 7:16pm
Off topic to the op and directed to Furcifer. At the point you chose to assemble a hard tail did you already have the knowledge and opinion you hold now? This is the part I cannot capiche. Why did you design something you understood wouldn't work. Could you tell us more about the components you used, specifically frame, forks, rims, hubs, tyres, tyre pressure, battery weight and position. Would you elaborate on how the frame is getting beat up, or the ride characteristics you find sub par. Finally could you give a short précis of your cycling experience.
I was under the assumption that a good hard tail would be able to withstand the rigors of city streets. I purchased an older Oryx (made in Canada) that had been modestly upgraded. A Manitou Minute through axle front shock, DT Swiss 2300 wheels with double walled rims and Avid Juicy 7 hydraulics (203 front and 160mm back discs) Right now I'm running Bontrager Elite 1.5" slicks @65psi. I have the battery in a soft pack that fits in the triangle, but also fits the on the rack. I'm pushing 200lbs, plus BBSHD 14lbs and a 21ah 52V that's about 10lbs. So probably 260lbs. GVWR

It's too much weight on the back wheel, especially with tires at 65psi. Moving the battery from the rack to the triangle doesn't seem to change much. It's better running a 2" tire at 40psi, but I've hit a few potholes where you cringe and listen for that pinch flat. I'm looking for a tire with a good sidewall and better wear. I think the Schwinn Cruiser 2.12" bike tire with kevlar looks like a much better tire for my needs.

The front shock works pretty good. I've got it tuned in now and it doesn't dive too much on braking, the rebound is fast enough for most road conditions and it doesn't bottom out. There's still a little too much flex in it for my liking.

This frame has fat chainstays, the main gear housing limits the offset, right now there's a 5mm spacer on the non-drive side. I had to glue a piece of nylon webbing to the frame to keep it from rubbing. If I forget to down shift enough, or I just can't, it will flex the chainstays enough to make it flex and squeak. And that's a couple inches from the motor, at the axle it's more, how much I can't say. If I had to guess I'd say 1/8". I check the QR skewers every other ride because I've had them come loose once.

On "good" pavement, where you might have a crack every 10 feet it's perfect. It's when you get imperfections every couple feet and you're at 25mph, the front is fine but the back end starts to bottom out. I think most riders know that feeling and sound when your bike bottoms out. Whether you're riding FS or not you can feel when you've hit the elastic limit and there's no more give. That's when you need to ride the bike with both hands and your body. It's no big deal coming down a hill or if you're by yourself, but if you're in traffic it's sketchy. I'm finding that in my area the pavement near stop lights and stop signs tends to be worse than other areas. Asphalt that's used by trucks a lot is terrible. There's a truck driving school near me and the pavement a block in either direction from it is terrible.

I don't know how much torque the BBSHD is putting onto the frame. To get an idea you can hold the back brake and stand on one pedal. You can feel the frame flex and see the bottom bracket move. Then try to pedal on the third cog, it takes some serious pedaling to get a bike to move from a dead stop. Then hit the throttle, that little motor doesn't even hesitate.

When you get a feeling for the torque it puts out you can kinda compare it to normal riding. I've broken plenty of chains riding and probably not with same amount of torque. I think the ramp up from the controller does a good job of rolling on power, and between the chain stretch and frame flex since I put a new chain on it hasn't broken. I think it would be interesting to put one on a BMX with the same chain and see what happens. BMX frames usually don't flex like mountain bike frames I my bet would be the BBSHD would snap chains quite frequently.

I've ridden old chromo 10 speeds, and mountain bikes as well as aluminum. Not much carbon fiber, I've never owned one myself but I have had one from the shop I worked at. Based on my experience riding I'd say if you're going to ride a rigid frame get something chormo. They don't flex anywhere near as much as aluminum, and flexing aluminum is not something you want to do very often. The only problem with that is you tend to give up the disc brake option. That's a tough call, but v-brakes are actually good and snapping a frame is very bad. If you are going to ride a rigid frame aluminum make sure you have downhill rims and fully adjustable front suspension. A wire bead tire with a thick sidewall and good tread at 30-40 psi is probably the only way to go. If you're going to be a road warrior and take on traffic for an hour or two every day go full suspension. I'm only doing a few miles a day right now, but I don't see this hardtail lasting very long. My gut feeling is if I would have went with a full suspension I wouldn't have to worry about taxing the bike as much and having to keep an eye on the frame and wheel true etc. By far the biggest shock I've had riding an ebike is finding out how crappy the roads are. The same roads I've ridden a bike on 100 times.

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