Many questions, wanna make a purchase!

ProDigit said:
I find it strange that on a 66cc engine, your top speed is only 40MPH!
The numbers just don't add up...

while on a 4 stroke scooter with 50cc you can get at least 40MPH.
The 2 stroke scoots (with variator) sometimes reach 60MPH.
Makes me question if the 66cc is really a 66cc, or a 33cc 2 stroke (2x stroke from a 4 stroke, thus compared to a 66cc 4 stroke)?

This makes me believe most people haven't optimized their bikes yet.
If the 2 stroke 49cc can get to 45MPH, with 29-32in wheels, and a 32T sprocket, I'd probably go with that one!

Again, being able to go 45 doesn't mean I'll go 45. It just means I'll be riding 28-32MPH more comfortably (on lower RPM's).
Click to expand...

There's not as much difference between the 48cc and 66cc as you would expect... It's a low quality 2-stroke without a transmission, so reel in your expectations, its not a scooter with a variator and gears in the rear end. IMHO if these are your goals you should go with a scooter. A Walmart bike is barely solid enough to pedal hard, riding with a motor at 28-30MPH is pushing it, going 40+MPH is over the top and asking for failure. Its not impossible to achieve these speeds, but you should start with a better bike more capable of taking the abuse, and you're going to have to optimize EVERYTHING for speed and do it well. Once you achieve those speeds you'll probably find it doesn't feel very safe on a Walmart bike, cause it isn't! On top of that, cops are finicky about motorized bicycles, you may get harassed a bit by some going under 30MPH, if you're going 40+MPH I would expect much more harassment from them. You have to ask yourself if all the effort is worth it, and if you will even be able to get away with riding the way you want if you achieve it, and how long it will be reliable when pushing it that hard? Like I said, not impossible, but it will take some doing, and put you through some paces. I have a scooter and a motorized bicycle, they both have their places, the scooter works better for riding in traffic at higher speeds, the motorized bicycle is more fun for cruising and going places cars cant go....
 
Here in Miami cops are pretty much unlearned.
They don't even know what a moped is, so they leave 2 wheeled vehicles mostly alone.

As far as the walmart bikes, they are meant to go 30MPH.
Any decent man can pedal 30MPH on a geared bike. A beach cruiser generally does not go very fast, but their frames seem pretty solid enough to go faster IMHO.

40MPH may be a lot, but then again, I'm only aiming for these speeds at WOT. More than likely I'll be running at ~ 2/3rd that speed.

The comment about the 50cc is pretty remarkable. I know that a 66cc is larger, has more torque, and top engine RPM's are about the same. But if you have better acceleration, then you could reduce the rear sprocket, compensating top speed with torque.
You might ask: Why do that, if you can get the same with a 50cc?
Well, if there's any wind, or uphill, a 60cc, even with slightly heavier gearing, will more than likely keep up, while a 50cc might not...
 
ProDigit said:
Here in Miami cops are pretty much unlearned.
They don't even know what a moped is, so they leave 2 wheeled vehicles mostly alone.

As far as the walmart bikes, they are meant to go 30MPH.
Any decent man can pedal 30MPH on a geared bike. A beach cruiser generally does not go very fast, but their frames seem pretty solid enough to go faster IMHO.

40MPH may be a lot, but then again, I'm only aiming for these speeds at WOT. More than likely I'll be running at ~ 2/3rd that speed.

The comment about the 50cc is pretty remarkable. I know that a 66cc is larger, has more torque, and top engine RPM's are about the same. But if you have better acceleration, then you could reduce the rear sprocket, compensating top speed with torque.
You might ask: Why do that, if you can get the same with a 50cc?
Well, if there's any wind, or uphill, a 60cc, even with slightly heavier gearing, will more than likely keep up, while a 50cc might not...
Click to expand...

Sometimes an "unlearned" cop adds up to a PITA to a motorized bicycle rider. Sure they ignore scooters, they are licensed and clearly legal, but a dirt bike is not street legal and so an motorized bicycle might end up on an "unlearned" cops radar where a scooter wouldn't. Specially if you're screaming around at 40MPH!

I don't think many people that buy a bike at Walmart hit 30MPH on them, and if they do it's down the biggest hill they will never climb back up again! LOL No amature cyclist is running around at a sustained 30MPH pedaling a bike the way you will with a motor on it. Not to mention the extra weight, and vibration, and required stopping power, and how much more impact those small bumps have on cheap rims when your moving that fast, or how the cheap bearings just don't hold up to that continued abuse very well. Or that you said you want to do ~40MPH for cruising in the burbs...

I am just trying to be honest with you, a cheap bike isn't up to the task as described by you in your original posting. You might get away with running a cheap bike as a casual cruiser, but to push into the 40MPH range for long roads out in the suburbs I would suggest you start out with something better, or adjust your expectations downward.

Speaking of expectations, don't get them too high or put too much faith in numbers you may see about these china girls. I have seen specs all over the board for engines that pretty much perform about the same. So you can run numbers all day, but good luck getting that from the paper to the pavement. I have heard said the motors were all designed to be 48cc and they up-sized the top end to make the 66cc, but the 48cc is a more balanced motor because of it. So don't expect the 66cc to be like the 48cc on steroids, maybe just on esspresso! lol

Not trying to rain on your parade, just trying to be real with you.
 
Not to mention NO single speed bike can achieve more than 25mph or so,geared from the factory. Now my bmx......52 tooth front chainring,16 tooth rear freewheel. That's high speed buddy.


Edit:just noticed you said 'geared'. Oops
 
66cc motor has 2.5 hp. add an expansion chamber and make it a 3hp motor and get a 40 tooth. Then you'll be hittinng 40mph. If you want to go higher, get a racing carburetor and 29 tooth and octane booster on your fuel. That will get you 45 mph +.

But really, the point of motorized bicycle is to "get there" just a little faster than a bicycle without having to pedal and not to drive it on center lanes like a motorcycle. It'll probably get you to places about the same as riding a bus minus the waiting.
 
I'm not really into performance, but MPG.
I don't mind if I have to help out the engine by pedaling from a stand still. The engine basically just has to push the bike and myself (a 6'3" 170LBS individual), over a flat surface, with slow to medium acceleration.
 
ProDigit said:
As far as the walmart bikes, they are meant to go 30MPH.
Any decent man can pedal 30MPH on a geared bike. A beach cruiser generally does not go very fast, but their frames seem pretty solid enough to go faster IMHO.
Click to expand...

How long can a "decent man" keep the speed of 30mph on a pedal bike?

motorized bicycle will be constantly going 30mph+ with crazy vibrations from the engine while non-motorized bicycles would go 30mph for a little while when you're pedaling like crazy minus the vibrations of a combustion engine
 
ProDigit said:
I'm not really into performance, but MPG.
I don't mind if I have to help out the engine by pedaling from a stand still. The engine basically just has to push the bike and myself (a 6'3" 170LBS individual), over a flat surface, with slow to medium acceleration.
Click to expand...

If you have a 66cc, you'll be fine with 40 tooth and still hit 40mph. 66cc chinese engines are wayyyyy underestimated. It'll even take 29tooth and still get you up hills as long as they're not that steep
 
The vibrations should be minimized, when RPMs get minimized through a smaller sprocket.
(One of the reasons I don't want a 41T sprocket...)

I understand most men can't maintain 30MPH (never said he was able to), however, most men can ride 30MPH, even if it is for a short time.
For the bike, I don't think there's much of a difference between riding 30MPH for one minute, or for half an hour, as most of the bike is solid fixed, and very little screws can come loose.

As for the frame, beach cruisers have very solid frames. Some mountain bikes also come with big bars.
The fixie bike, or sports bikes may be too thin though...

The Chinese bikes of today,are about as good as the middle class bicycles of the 1980's made in Europe (or USA).
They have more comfort for lower prices, but generally the frame is a little less good.
 
ProDigit said:
The vibrations should be minimized, when RPMs get minimized through a smaller sprocket.
(One of the reasons I don't want a 41T sprocket...)

I understand most men can't maintain 30MPH (never said he was able to), however, most men can ride 30MPH, even if it is for a short time.
For the bike, I don't think there's much of a difference between riding 30MPH for one minute, or for half an hour, as most of the bike is solid fixed, and very little screws can come loose.

As for the frame, beach cruisers have very solid frames. Some mountain bikes also come with big bars.
The fixie bike, or sports bikes may be too thin though...

The Chinese bikes of today,are about as good as the middle class bicycles of the 1980's made in Europe (or USA).
They have more comfort for lower prices, but generally the frame is a little less good.
Click to expand...

IMHO most of what you said above is just wrong. The motor is going to vibrate, ever run a china girl 2-stroke before? It's gonna vibrate! Most riders that pedal don't hit 30MPH, Walmart bikes were NOT designed to ride at 30MPH. Theres IS a HUGE difference between hitting 30MPH for a second and sustaining that speed for ride after ride. Not only can things vibrate loose, search the forum and read about cracked frames, not to mention failed bearings and breaks not up to stopping your once you are going 30+MPH. The idea that a cheap chinese bike is as good as a mid grade bike from Europe in the 80's is a joke IMHO. I don't know how old you are, but I was riding bikes in the 70's and 80's and things were built way better back then, the quality of metal alone is of a different class, metals and welds coming from China these days are not up to par compared to what was manufactured back then. Ever heard about the bridge in Cali (I think San Francisco) that they bid out to china, when received and assembled it wasn't strong enough to support the weight it was rated for. Read up, thats a BRIDGE, something that is critical and must be up to strength, not just a Walmart bicycle!
Again, not trying to rain on your parade, but I honestly believe you are off base with some of your assertions here.
 
Kinda like the unlearned cops. Really? The state of florida makes its money off locking people from outta state up,how unlearned could they be? When I lived down there the saying was(and probably still is)

Come on vacation,get stuck on probation.
 
Hey,
I don't know if you've ever looked at the bikes they sell in WM. The frames may be out of aluminum, but esp. the beach cruisers have gigantic tubes in their frames!
In europe (I'm 33, lived there 50% of my life), the frames are finger thin.
They are high quality steel though, yes, but you did not have the quality disc brakes back then; everything was V-brake.
The saddles of today are leaps and bounds ahead of the older ones in comfort and affordability. Front disc brakes did not exist for bikes in the 70's to the 1990's. They only appeared after the millennium.
And even the rims, though being steel in europe, bent when hitting the sidewalk (due to the thin profile tires).
Plenty of WM bikes that have such big tires, that unless you're having a flat, you won't ever bend the rim!

I honestly believe that esp. the beach cruisers are more than capable of maintaining the 30MPH speeds. I used to ride a couple of bikes in my home country in europe for over 13 years, and all of them lasted at least 7 years! The last one I had was from china too; a city bike (mountain bike equipped with lights, reflectors, mud guards, luggage rack etc...). That bike retired with the final gear rear sprocket completely worn after 4 years; but is still in use by someone else riding in second to final gear.
(and did I tell you it was chinese, and had thinner frame than the beach cruisers in WM?)

Ow, and about the rambling apart, tell me exactly what there is on a bike (like a beach cruisers, or a Mountain bike fwiw) that can ramble apart?
Because as far as I see it, there's really not many things that can ramble apart!

Overheating wheel axis? Come on, that's a joke!
I've never in my life seen a wheel overheat, especially not the aluminum ones.

Cracked frames, well, perhaps people running a 56T sprocket will have more problems with that due to aggressive acceleration..., or aggressive zig-zagging at high speeds. But take care for your bike, and it'll last. It's good enough to sustain itself in emergencies, but don't make every brake or acceleration an emergency, because then indeed, your bike may not last very long...

I don't know, I think you don't agree with me, but that does not necessarily make my opinions or statements incorrect.
 
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ProDigit said:
Hey,
I don't know if you've ever looked at the bikes they sell in WM. The frames may be out of aluminum, but esp. the beach cruisers have gigantic tubes in their frames.......And even the rims, though being steel in europe, bent when hitting the sidewalk (due to the thin profile tires).
Plenty of WM bikes that have such big tires, that unless you're having a flat, you won't ever bend the rim!

I honestly believe that esp. the beach cruisers are more than capable of maintaining the 30MPH speeds. I used to ride a couple of bikes in my home country in europe for over 13 years, and all of them lasted at least 7 years! The last one I had was from china too; a city bike (mountain bike equipped with lights, reflectors, mud guards, luggage rack etc...). That bike retired with the final gear rear sprocket completely worn after 4 years; but is still in use by someone else riding in second to final gear.
(and did I tell you it was chinese, and had thinner frame than the beach cruisers in WM?)

Ow, and about the rambling apart, tell me exactly what there is on a bike (like a beach cruisers, or a Mountain bike fwiw) that can ramble apart?
Because as far as I see it, there's really not many things that can ramble apart!

Overheating wheel axis? Come on, that's a joke!
I've never in my life seen a wheel overheat, especially not the aluminum ones.

Cracked frames, well, perhaps people running a 56T sprocket will have more problems with that due to aggressive acceleration..., or aggressive zig-zagging at high speeds. But take care for your bike, and it'll last. It's good enough to sustain itself in emergencies, but don't make every brake or acceleration an emergency, because then indeed, your bike may not last very long...

I don't know, I think you don't agree with me, but that does not necessarily make my opinions or statements incorrect.
Click to expand...

OK, for now we can agree to disagree, when you gain more experience with a MOTORIZED bicycle you are free to change/adjust your opinion! As I said before, the quality of the metal and WELDS on these bikes are poor, and fail DUE TO VIBRATIONS caused by the MOTOR and excessive stress put on them by the extra weight and speed that is attained when the MOTOR is added. The bearings are another area of failure, and the rims take a pounding no matter how thick the tires are because of the SPEED you travel with the MOTOR on the bike.

If you haven't gotten what I am trying to tell you, a MOTORIZED bike has to be a lot more solid than a bike you plan on pedaling, specially if you plan to push the bike into the 40MPH range, which is above the average speed attained by a kit bike.

You're not the first one who has come to this forum thrilled to find such cheap and "capable" bikes at Walmart. I have seen others do the same and in a matter of months post back that they are scrapping their bike and starting on a second build with a better bike. So have at it, I wish you success, and I also wish if and when your bike has a failure you do not injure yourself....
 
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Yes,a wally world special is exactly what you need. After you wake up in the hospital I won't say I told you so. Can't speak for everyone else though.
 
I've heard a lot of this talk on a lot of forums.
There's a reason behind it. And most of the time that reason is fear... Fear that people could actually buy a cheap bike that's good enough to sustain whatever they need, and that they will not receive sales through their own channel.

The bike store too, telling me how bad these kits are for the bicycles, showing how the sprocket killed the spokes.
Then I think to myself, EZ remedy! Get a smaller sprocket, that means less torque on the spokes, accelerate a bit more careful, and make sure that the spokes are all tensioned correctly, and these things will last just fine!

In every category, there's going to be an idiot, trying to "tune" the thing to make it go like a rocket, and in the process overburden some parts.
Same on scooters, and then they wonder why the belts break...

I've heard a lot of 'warnings' from people saying the same thing about chinese scoots (they usually work in Vespa or other brand stores).
Well let me tell you,
my $800 Chinese scooter, has over 2500 trouble free miles on them, and more to go!
Worth buying?
Every penny of it!
What would I have gained if I had purchased a Vespa?
Probably less minor adjustments where necessary, fewer oil changes; and perhaps the comfort level was a bit better.
But I would have lost over 3-4x the amount of money as on my chinese scoot, and the vespa's aren't even performing as good as my china bike.

So moral of the story:
There are always nay-sayers on every forum.

I'm sure some of your fears are grounded on the weakest of bicycles, but you're not going to tell me that a cruiser bike's frame is not supporting the engine.

In my early years, I was an avid bicycle rider. I rode with average speeds of 20-25MPH (usually did very short trips, less than 20 minutes, but also did occasional 1,5 hour rides)
In the short trips, my speed often surpassed 30 mph (esp with wind in the back).
In the long trips I rode less agressive.

If there was anyone that torqued the frame, it was me. And on one of my bikes I did manage to break the frame on the pedals, because of hard acceleration, causing the frame to wobble when riding without hands.

But that bike was nowhere comparable to the Mountain and cruiser bikes I see in Walmart today.
Even I think I'll have a hard time bending those frames!

But then again, the way I plan on using the bikes is totally different from most people
Most just want fast acceleration.
I want low RPM, and great gas mileage, and will be using the engine in the lower end of the rev range.

And again, to be able to do 40-45MPH doesn't mean I'm always going to ride at those speeds.
I just set up the bike like this, to lower RPM, and increase MPG, and lower engine wear in the process.

On top of that, the Genesis Onyx bikes are hardly to be called 'weak bikes'.

I mean, overall I agree with your statement that there is danger, and there are bikes in WM that are very fragile.
But not all of them are (take a look at the fat beach cruiser they're selling now. I don't think any bike in the bicycle store (even with a steel frame), can topple that one in terms of rigidness.
 
I want you to know that I am not trying to discourage you, and I don't have any agenda. I don't sell bikes, motors, parts or service of any kind related to bicycles or motor kits for them, and have no association with the ownership or management of any company that does, or any forum on the topic.

All I'm saying is perhaps you should build a motorized bicycle and run one of these HT motors before you disagree so firmly with those that have. They vibrate and stress a bike like no human being can, no bikes were built for that and the cheapest ones don't hold up to it so well. I could go over your last post and disagree with several of your assertions, but I think I have made my points and you have made yours. I wish you well with your build and hope it turns out to be every bit as solid as you expect. I will close by asking you to pay close attention to the BRAKES on the bike you ride, cause you're gonna need 'em and how if you are as successful as you hope to be.

Just giving a fellow rider my opinions, and will be glad to help you achieve your goals in any way that I can during your build. Good luck and happy riding!
 
I was aware of the brakes, however, there are solutions for that; like installing a disc brake.
If worst comes to worst, it's always possible, to use the coaster brake, 2 Vbrakes, and if that's not enough, add a front disc brake. That will give you 4 active braking systems on a bike; that is, if you think it's necessary to add that many.
But it is kind of silly because then you might as well buy a real bike like you say.

The brakes worries me, because I can not install a disc brake on the front without mounting points. Just the disc brake and a comfy saddle, brings the bike in $250 territory.

Then it's upto the rider to decide if he wants to go cheap, and ride carefully, or buy what's necessary to be safe, but go expensive.
I think, since for many it's a toy, not a reliable transport, that they want to keep it cheap.

It wouldn't surprise me, if the chinese will start selling these bike kits already mounted on bicycles, soon.
 
ProDigit said:
I was aware of the brakes, however, there are solutions for that; like installing a disc brake.
If worst comes to worst, it's always possible, to use the coaster brake, 2 Vbrakes, and if that's not enough, add a front disc brake. That will give you 4 active braking systems on a bike; that is, if you think it's necessary to add that many.
But it is kind of silly because then you might as well buy a real bike like you say.

The brakes worries me, because I can not install a disc brake on the front without mounting points. Just the disc brake and a comfy saddle, brings the bike in $250 territory.

Then it's upto the rider to decide if he wants to go cheap, and ride carefully, or buy what's necessary to be safe, but go expensive.
I think, since for many it's a toy, not a reliable transport, that they want to keep it cheap.

It wouldn't surprise me, if the chinese will start selling these bike kits already mounted on bicycles, soon.
Click to expand...

Now thats the kind of logical talk and reasoning we all need to go through when building a motorized bicycle...
BTW, there are already a few chinese frames built specifically to mount these motors on already, and some complete bikes and kits available as well, not sure if they are all available on our shores yet but they are out there...
 
It all boils down to your skill building and maintaining the bike. I ride a cheap POS Next that most people would say cannot take what I do to it every day. It stays running because I identify and fix any potential problems long before anything fails. You sound like you have some bike experience so you should be okay with a cheaper bike to start with. I also think you are DEAD WRONG thinking motorized bikes are the same as human powered bikes as far as the stresses the bike sees. You may not have ever seen a hub seize solid and self destruct because you have never ridden ANY bike at the sustained speeds and loads the motor can impart. Just tooling around at cruising speed will put more stress on the bike than a human riding at 99% would. Don't underestimate the potential for serious failure and injury if you don't know what you are doing.
If you treat the bike right, there is no reason you cannot get years of fun and reliable service from a wallyworld special. Just don't think it will be easy because you already ride a bike. A motorized bike is a whole different world as you will discover.
Buy the bike you like and TAKE GOOD CARE OF IT and you will be fine. Study the numerous threads on budget builds, there is a LOT you need to learn to stay happy and safe as you explore the thrill of riding your newly built motorbike!
 
Your $800 scooter did fine because it was built as a scooter or a "motor driven cycle." These bikes that can keep up with the traffic and are allowed access to a full lane are designed to withstand vibrations. Even the cheapest and crappiest scooters will at least have some engineer work on safety and vibration issues or else it probably wouldn't have made it to US as a street legal vehicle to begin with.

And let me tell you something, I actually did try ALL performance upgrades possible on a chinese engine on my first 66cc build

I had 66CC flying horse motor, SBP jack shaft kit and 8 speed cassette, 11 tooth sprocket, CNS Racing Carburetor, SBP Expansion exhaust, iridium sparkplug. ALL of them on a 150 dollar Walmart bike. I did hit my dream speed of 45 mph on my eighth gear.

I made sure I welded up all these performance parts properly instead of using brackets and sillicons.

The result was everything about the engine and the motor kit was fine but all the torques and bolts were falling apart on the bicycle aspect of the vehicle. Later on the thin rear end of the bike frame that holds the wheel was almost about to snap. Not to mention one out of every two rides, the torque on my handle bar would get loose, so on short rides when I don't have my tools in my backpack, I had to pull off some crazy stuff to maneuver my bike with a wiggly handlebar. That's when I realized the whole thing was freaking dumb and reverted everything back to stock.

You said "there's going to be an idiot, trying to "tune" the thing to make it go like a rocket, and in the process overburden some parts." And anything over, and even slightly over 35 mph on a walmart bike IS "making it go like a rocket." 45 on a bicycle is CRAZY. Not to mention that they don't have the same aerodynamic designs of a motorcycle. So you're gonna have to fight the wind resistance crazy hard once you go even 1 mph over 35.

Even when i'm going about 20~30 mph on my mostly stock engine kit bike, I took the bike to the welding shop to weld reinforcements on the weaker part of the frame.

You said you're more interested in MPG then performance. But for MOTORIZED BICYCLE 40mph IS EXTREMELY high performance. And actually the low MPG is a package deal with the relatively low speed. Once you install all these performance parts to get your desired speed, you'll go through those half gallon/1 gallon tanks so fast.

Even at 25 mph, I still get to places on time and I make spandaxers eat my dust.

But anyways if you really really really wanna do this, go get a morini and a worksman bike.
Worksman bikes are practically indestructible. But at that point, you might as well buy another scooter with that money
 
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