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

furcifer said:
There's no benefit of a rigid frame. In fact the opposite is true. That's just a fact. It seems odd to even argue it, there's +100 years of automotive technology to prove this. You can ride a rigid frame but it's stupid. I'm not sure what else there is to say?
Click to expand...

You're simply wrong. A rigid frame has many advantages:

Longevity
Structural integrity
Weight
Maintenance
Mounting options
Internal space
Parts compatibility
Cost

Bicycles have been iterated for over 150 years, since before cars were a thing, and the vast majority of them are still rigidly framed. I think you're going out of your way to disregard what the rest of the world already understands. "More is more" doesn't work with bicycles. It turns them into something else that isn't as good as a bicycle.

Suspension bikes are toys designed primarily for people to spend money on. That's why there are few interchangeable standards for their suspension components-- you "fix" the bike by buying a new one. Real transportation bikes almost all have rigid frames, with a high degree of intercompatibility.
 
Of course that's 150 years of non-motorized bicycles, contrasted against motor scooters and motorcycles where suspension is ubiquitous. That doesn't by any means prove that a motorized bicycle needs full suspension, I just think people are taking sides on this because of over-simplification. There are different ways to go with a motorized bicycle, some more bicycle-like and others more scooter, in various ways including simply how fast. People ride different surfaces and traffic conditions, etc. Some ordinary "rigid" bicycles are a lot less rigid than others. Take a racing geometry with a hard leather saddle and skinny tires - please! Some riders would love that as a platform for a 30mph hub motor - after all, a bicycle like that is for fast riding - but others would justifiably think that's pretty stupid.
 
wturber said:
A bicycle is not an automobile.
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No, but almost all ebikes are motorcycles. The build the OP is talking about actually puts him in this category.

Not recognizing this is your mistake. There aren't any motocycles without suspension anymore for a good reason. SAFETY.
(talk to some hard tail riders)

It's just foolish to neglect safety and comfort. I don't know why anyone would.
 
Chalo said:
You're simply wrong. A rigid frame has many advantages:

Longevity
Structural integrity
Click to expand...

Sorry, like your argument, this is pure nonsense. Suspension is specifically designed to reduce vibration, which improves both structural integrity and longevity.

Is it opposite day?
 
furcifer said:
No, but almost all ebikes are motorcycles. The build the OP is talking about actually puts him in this category.

Not recognizing this is your mistake. There aren't any motocycles without suspension anymore for a good reason.
Click to expand...

It's your mistake, too. There are for example thousands of electric rental bikes in my city. They are not motorcycles by any stretch of the imagination, and ebikes like that far outnumber the "motorcycle" bicycles. The OP can build whatever he wants, and doesn't have to ride it like a motorcycle, so it isn't just about categories of build either. Some riders are a lot better off with suspension, while for others it apparently isn't worthwhile (though I am not sure I find the arguments presented here against it very compelling.)
 
extensively used every extreme

span quality full - rigid

low pressure fat tire favorite

roughly 25mph performance envelope

all terrain performance

good comfort less complicated

excellent choice for bbshd
 
donn said:
It's your mistake, too. There are for example thousands of electric rental bikes in my city. They are not motorcycles by any stretch of the imagination, and ebikes like that far outnumber the "motorcycle" bicycles. The OP can build whatever he wants, and doesn't have to ride it like a motorcycle, so it isn't just about categories of build either. Some riders are a lot better off with suspension, while for others it apparently isn't worthwhile (though I am not sure I find the arguments presented here against it very compelling.)
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I don't think it's a mistake. The BBSHD is a 1000W which classifies it as a motorcycle in most of the world.

People arguing against full suspension, IMO, ARE THE REASON FOR THIS. They're too stupid to know that going this fast on a vehicle and using public roads is dangerous so the government needs to step in and protect them from themselves.

OP wants to average 24mph, that's pretty much full out on a BBSHD. The law basically says you're a motorcycle at that point. So it's pretty good practice IMO to use similar safety requirements. Suspension, proper brakes, marker lights, horn etc.

Not doing this is irresponsible even if it's not absolutely necessary.
 
furcifer said:
Chalo said:
You're simply wrong. A rigid frame has many advantages:

Longevity
Structural integrity
Click to expand...

Sorry, like your argument, this is pure nonsense. Suspension is specifically designed to reduce vibration, which improves both structural integrity and longevity.

Is it opposite day?
Click to expand...

Suspension frames wear out through articulation and mechanical play. They by their nature can't function as trusses like rigid frames, so they lack bracing that would multiply their integrity if they had it.

I've worked in bike shops since before bicycle suspension was an active fad, so I have seen over and over that a ten year old suspension bike is clapped out in a way that a rigid frame never becomes, regardless of age. A rigid frame can crack, just like a suspension frame can. But a rigid frame can't become a wobbling, creaking, clunking mess like a suspension frame does over time. A 40 or 50 year old rigid bike tunes up and rides just like new. Before it's a third that old, a suspension bike is a laughable shambles that you can't even get parts for anymore. But it doesn't really matter, because it's a toy. Doing a real bike's work is not what it's for.
 
furcifer said:
wturber said:
A bicycle is not an automobile.
Click to expand...

No, but almost all ebikes are motorcycles. The build the OP is talking about actually puts him in this category.

Not recognizing this is your mistake. There aren't any motocycles without suspension anymore for a good reason. SAFETY.
(talk to some hard tail riders)
Click to expand...

Nope. Most are actually bicycles as is the OP's build. An average top speed of around 25 mph is bicycle, not motorcycle speed. 28 mph max assisted speed is Class 3.

furcifer said:
It's just foolish to neglect safety and comfort. I don't know why anyone would.
Click to expand...

There is no neglect of safety here. Bikes have been operated in the 25 mph range safely almost since they were invented. The comfort question is open to debate. I'll trade a little bit of comfort for the advantages of a solid frame. And there are all kinds of seats and seatposts that address that.
 
furcifer said:
People arguing against full suspension, IMO, ARE THE REASON FOR THIS. They're too stupid to know that going this fast on a vehicle and using public roads is dangerous so the government needs to step in and protect them from themselves.
Click to expand...
FWIW, I'm not against suspension. I just see it as having pros and cons. You pick based on how those weigh out for you.
furcifer said:
OP wants to average 24mph, that's pretty much full out on a BBSHD. The law basically says you're a motorcycle at that point. So it's pretty good practice IMO to use similar safety requirements. Suspension, proper brakes, marker lights, horn etc.

Not doing this is irresponsible even if it's not absolutely necessary.
Click to expand...

Nope. You've misread his post. That's the average top speed he wants, not the average speed. He wants to cover 12.5 miles in about 40 minutes average. That works out to around 19 mph average speed. That's right at my average and I've done 7700 miles in about 20 months like this on a hardtail with front suspension similar to the bike the OP is intending to use. These are bicycle speeds.
 
wturber said:
That's the average top speed he wants
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This doesn't make sense either. You have an average speed and a top speed.

At the bare minimum you're going to want a good front suspension fork. Which is another thing, a lot of front suspension forks are garbage. Even the good ones don't come properly tuned for a 280lb rider with 30lbs of gear. Most spring shocks come with springs intended for a 150lb rider. Even heavy duty springs aren't intended for that kind of weight.
 
furcifer said:
wturber said:
That's the average top speed he wants
Click to expand...

This doesn't make sense either. You have an average speed and a top speed.
Click to expand...
If you read his whole post and try to understand what he wants, it isn't hard to make sense of it. What he meant was "typical high speeds of about ..."

furcifer said:
At the bare minimum you're going to want a good front suspension fork. Which is another thing, a lot of front suspension forks are garbage. Even the good ones don't come properly tuned for a 280lb rider with 30lbs of gear. Most spring shocks come with springs intended for a 150lb rider. Even heavy duty springs aren't intended for that kind of weight.
Click to expand...

I've ridden thousands of road bike miles at around 20 mph on 700x25c road tires pumped to 110 psi. 2 inch tires at 50 psi are just fine at 25 mph on a rigid front fork.

As for good gear, that is one of the negatives. Added cost. And now you have to modify and maintain it. More cost and hassle.
Things just aren't as cut and dried as you make them out to be.
 
wturber said:
Nope. Most are actually bicycles as is the OP's build. An average top speed of around 25 mph is bicycle, not motorcycle speed. 28 mph max assisted speed is Class 3.
Click to expand...

This is incorrect as well. Both Canada and the US have similar federal laws and both are well under 1000W. (500W and 750W respectively)

You keep using "average top speed", there's no such thing. It's weird.

And no, bicycles aren't operating at a sustained 25mph. That's like world class cycling on a road bike speed. Even then a cyclist is putting out only about 250 watts. In general bikes are made to go about 10mph.

The weight and power we are talking about with a 1000W BBSHD is equivalent to a moped or small motorcycle. Legally.

I think of it like this, even a really good full suspension bike is under what would be considered "properly engineered" for 1000W. If you were to actually engineer a 1000W ebike you'd probably double the frame thickness, use 2in rims, have shocks designed for about 400lbs of weight etc. Some of the downhill bicycles are close to these type of specs but they are designed with gravity as the motivating force, not a motor.
 
wturber said:
I've ridden thousands of road bike miles at around 20 mph on 700x25c road tires pumped to 110 psi. 2 inch tires at 50 psi are just fine at 25 mph on a rigid front fork.

As for good gear, that is one of the negatives. Added cost. And now you have to modify and maintain it. More cost and hassle.
Things just aren't as cut and dried as you make them out to be.
Click to expand...

*sigh

You don't seem to understand, you're only putting out about 200 watts, NOT 1000W. We're talking 5 times the power!

Surely you get the idea that as you scale up the power you need to scale up the components? It's very basic.
 
Chalo said:
furcifer said:
Chalo said:
Suspension frames wear out through articulation and mechanical play. They by their nature can't function as trusses like rigid frames, so they lack bracing that would multiply their integrity if they had it.

I've worked in bike shops since before bicycle suspension was an active fad, so I have seen over and over that a ten year old suspension bike is clapped out in a way that a rigid frame never becomes, regardless of age. A rigid frame can crack, just like a suspension frame can. But a rigid frame can't become a wobbling, creaking, clunking mess like a suspension frame does over time. A 40 or 50 year old rigid bike tunes up and rides just like new. Before it's a third that old, a suspension bike is a laughable shambles that you can't even get parts for anymore. But it doesn't really matter, because it's a toy. Doing a real bike's work is not what it's for.
Click to expand...

Nonsense. You just need to maintain the components. People using full suspension bikes are pushing them harder because that's why they bought them.

Which is the point. A 1000W electric mid-drive is really pushing well beyond the limits of bicycle design, even if it has full suspension. Like I mentioned before, downhill bikes come close but still fall a bit short. They use gravity and they're not made to sit on and ride.

I still think you guys are crazy. I mean yes, you can ride a rigid frame but why? You know full well that full suspension bikes are much more suited to the kind of abuse these electric motors put them through.
Click to expand...
Click to expand...
 
furcifer said:
wturber said:
Nope. Most are actually bicycles as is the OP's build. An average top speed of around 25 mph is bicycle, not motorcycle speed. 28 mph max assisted speed is Class 3.
Click to expand...

This is incorrect as well. Both Canada and the US have similar federal laws and both are well under 1000W. (500W and 750W respectively)
...
And no, bicycles aren't operating at a sustained 25mph. That's like world class cycling on a road bike speed. Even then a cyclist is putting out only about 250 watts. In general bikes are made to go about 10mph.

The weight and power we are talking about with a 1000W BBSHD is equivalent to a moped or small motorcycle. Legally.
Click to expand...

The legal classification of electric bicycles is thoroughly irrelevant. Luckily, because it's utter BS. Bicycles don't operate at some narrow characteristic speed range, they go real fast down hill and real slow up hill. We're not going to arrive at useful and enjoyable electric bicycle design by consulting the legal classifications.

Like the man said, things aren't that cut and dried.

The durability issue is another one like that - should we consider here, how long the whole ebike build will last? Do you care about a frame that was acquired for that purpose, after the battery died and the motor is obsolete ... maybe 3 years? Are you going to rehabilitate it as the pedal-only bike you never wanted? I don't know, maybe a big deal for some owners, maybe not the biggest consideration for others.
 
furcifer said:
Which is the point. A 1000W electric mid-drive is really pushing well beyond the limits of bicycle design, even if it has full suspension.
Click to expand...

Is that so?

https://www.google.com/amp/s/www.cyclingweekly.com/news/racing/data-reveals-the-most-powerful-sprints-of-2018-and-the-numbers-are-pretty-mind-blowing-359140/amp

Keep in mind that these bikes weigh about 16 pounds, average about 25mph over the course of an entire event, and have no suspension whatsoever.

You seem to have a Walter Mitty type of issue about your equipment. But neither the OP nor any of the rest of us need to be burdened with such counterproductive ideas.
 
Yeah well those numbers (1500W, 1900W) are probably for juiced riders, like Lance Armstrong.
Just saying :wink:
:lol:

PS
Please don't ask what my manual output wattage is, I will install the KMC soon enough.
 
donn said:
The legal classification of electric bicycles is thoroughly irrelevant. Luckily, because it's utter BS. Bicycles don't operate at some narrow characteristic speed range, they go real fast down hill and real slow up hill. We're not going to arrive at useful and enjoyable electric bicycle design by consulting the legal classifications.
Click to expand...

The speed limits imposed on "low speed vehicles" aren't arbitrary, which is the point I'm making. Just about every country has similar restrictions and what they consider a "safe operating speed". Take a look at a moped, they're basically designed to go 30mph. Just about everything on a moped is slightly beefed up compared to a bicycle. It's not because companies like to use heavier frames, thicker spokes and bigger bearings, it's because it's needed to withstand the forces at the designed speed.

Sure you can do 100mph on a bicycle but that doesn't mean it was designed to go 100mph.

I don't know what the actual speed bicycles are designed for. My rough guess is about 10-15mph. I've seen kids wreck box store bikes in a couple weeks riding much less than 25mph. Cheap Chinese components can't hold up to 100lb rider, putting out 200W, at about 15mph.

I'm trying to put numbers to this so you can see what I mean. I'm not sure if this helps you or not?

Do you guys own a BBSHD? I've ridden one for 5 months now. It's on a bike that would have been about $2000 when it was new (paid $300). It's not full suspension and the BBSHD is kicking the crap out of it. There's absolutely no question in my mind that this bike, as good as it is, is simply not designed to carry my 200lbs and the 40lbs of motor and battery. I'm surprised I haven't snapped an axle yet.
 
Chalo said:
Keep in mind that these bikes weigh about 16 pounds, average about 25mph over the course of an entire event, and have no suspension whatsoever.
Click to expand...

Keep in mind you're comparing a $7000 road bike, that gets tuned and rebuilt every 100 miles, made with the best components money can buy.

I think you made my point. If you want a rigid frame bicycle that can handle what the BBSHD puts out (for 20 seconds) plan on paying at least $5000. :mrgreen:
 
furcifer said:
The speed limits imposed on "low speed vehicles" aren't arbitrary, which is the point I'm making. Just about every country has similar restrictions and what they consider a "safe operating speed".
Click to expand...

Fine, and what speed one travels at, is certainly an important design consideration. But legal classifications revolve around power - 250W this, 750W that, etc. You're telling us he's a motorcycle because 1000W. That's baloney. It sounds like you've ridden motorcycles. Mine had a fairly modest top speed somewhere above 110mph if I remember right. I tried that once. It had that potential, but only for someone foolish enough to use it - you can't tell how fast I normally rode, from knowing that I had a 1000cc motorcycle. And you can't really infer from that 110mph how many HP, or vice versa. Power ratings don't really answer any questions about how a bicycle should be designed, or for that matter even how much power it's going to have - you don't really know what "1000W" means without lots more details.

If he thinks he's riding a bicycle, it's a bicycle. If he thinks he's riding a moped, I guess it's a moped. The design parameters are just blanks that have to be filled in after considering what the rider's up to.

I sure don't have a BBSHD (and my thought is that the OP would be better off with a simple direct drive hub.) Your experience with it might lead to some valuable insight into the design issues, like maybe there's a PAS issue that puts some stress on the system? Which would be more useful than this silly suspension crusade.
 
furcifer said:
Chalo said:
Keep in mind that these bikes weigh about 16 pounds, average about 25mph over the course of an entire event, and have no suspension whatsoever.
Click to expand...

Keep in mind you're comparing a $7000 road bike, that gets tuned and rebuilt every 100 miles, made with the best components money can buy.

I think you made my point. If you want a rigid frame bicycle that can handle what the BBSHD puts out (for 20 seconds) plan on paying at least $5000. :mrgreen:
Click to expand...

That's a fallacy. Affordable (but not horribly cheap) bikes are stronger and more durable than ones built to the minimum racing weight limit.

And of course you don't get to where you can put out nearly 2hp in a race without having done it lots of times when training.

Tandems go faster than single bikes, with twice as much weight. They don't use suspension either. Most bikes don't, at any price. It makes little sense for the street, and it costs performance and versatility in other ways.
 
donn said:
You're telling us he's a motorcycle because 1000W. That's baloney.
Click to expand...

Not me dude, that's the law in most countries. I think it's stupid too but it does reinforce my point that 1000W is enough turn a bicycle into a motorcycle both figuratively and literally.

I had a 98 GSXR750, first year they were fuel injected. I hit 240km/h going up this bridge (Hamilton,ON) without realizing it. I slowed down by the middle and just when I got over the hump I could see a full on radar trap at the bottom; tripod mounted laser and multiple chase vehicles. Luckiest day of my life. I sold the bike shortly after. The bike was geared to do 300km/h, I don't know what it was designed to do, but I am not designed to go 300km/h.

The fact that my bicycle and that GSXR are both considered motorcycles under the law is hysterical.

Anyhow, this is my insight. I believe most rigid frames aren't up to the task of making a BBSHD commuter. My thoughts are that it will get pretty beat up over a year, and so will the rider. His ride doesn't seem to hilly and a 1000W hub motor on a Sun Ringle MTX33 rim might be a better choice. I think with that he could probably get away with a 52V 14ah shark pack.

It seems counter-intuitive but I think the hub motor is more suited to a rigid frame.
 
Chalo said:
furcifer said:
Chalo said:
Keep in mind that these bikes weigh about 16 pounds, average about 25mph over the course of an entire event, and have no suspension whatsoever.
Click to expand...

Keep in mind you're comparing a $7000 road bike, that gets tuned and rebuilt every 100 miles, made with the best components money can buy.

I think you made my point. If you want a rigid frame bicycle that can handle what the BBSHD puts out (for 20 seconds) plan on paying at least $5000. :mrgreen:
Click to expand...

That's a fallacy. Affordable (but not horribly cheap) bikes are stronger and more durable than ones built to the minimum reaching weight limit.

And of course you don't get to where you can put out nearly 2hp in a race without having done it lots of times when training.

Tandems go faster than single bikes, with twice as much weight. They don't use suspension either. Most bikes don't, at any price. It makes little sense for the street, and it costs performance and versatility in other ways.
Click to expand...

You think riders use their race bikes to train? Are you sure you worked in a bicycle shop and not for Bicycle making playing cards? :mrgreen:

I'm not sure if you're talking about frames or components??? "Affordable" bikes have cheaper components that don't last as long as good ones. I have a Shimano 600 groupo that's 30 years old and probably got 10 000 miles on it. It's in better condition than new ones on an "affordable" bike. If you're talking about frames then yes, I agree with you there.

Most bikes don't have suspension. Every other vehicle on the road does. So do golf carts for that matter. Forklifts don't, and that's exactly the kind of ride you'll get with a rigid frame bike.

eta: you guys are fun. I didn't even think this was debatable.
 
furcifer said:
Chalo said:
Affordable (but not horribly cheap) bikes are stronger and more durable than ones built to the minimum reaching weight limit.

And of course you don't get to where you can put out nearly 2hp in a race without having done it lots of times when training.

Tandems go faster than single bikes, with twice as much weight. They don't use suspension either. Most bikes don't, at any price. It makes little sense for the street, and it costs performance and versatility in other ways.
Click to expand...

You think riders use their race bikes to train? Are you sure you worked in a bicycle shop and not for Bicycle making playing cards? :mrgreen:

I'm not sure if you're talking about frames or components??? "Affordable" bikes have cheaper components that don't last as long as good ones. I have a Shimano 600 groupo that's 30 years old and probably got 10 000 miles on it. It's in better condition than new ones on an "affordable" bike. If you're talking about frames then yes, I agree with you there.
Click to expand...

My first bike shop mechanic job was in 1992. I know what lasts, and what doesn't. I use steel chainrings, for instance (cheap), when I want them to last. Shimano 600 is pretty nice, but nothing special. Sachs New Success is hardier and nicer looking in any generation, and never cost more than 600/Ultegra. Dura Ace (the "good" stuff) is more likely than not to be deciduous crap. The few decent bits that hang around manage to color people's opinions about the product line overall.

But what isn't even in the same ballpark is the endurance of suspension bikes (abysmal) versus normal bikes of any price range above Wally World garbage. You can have any pet idea you want about them, but suspension bikes go to shit at a young age. Even the ones that only see pavement and tame riders. Squish bikes from two seasons ago are already making a racket, and by the point where it's time to overhaul a normal bike to bring it back to like-new, you can't even overhaul the boinger because the manufacturer has stopped supporting it.
 
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