2 stroke gas/350w front hub full Regen project

O

Olds C0ol

10 µW
Joined
Jun 20, 2019
Messages
5
My gas range is 200+ miles. Looking for a 350w direct drive front hub with positive Regen capability. Iam 70, legs are shot, life in Alaska, USA, is not a short cake walk to get anywhere. Long range is mandate. Can no longer pedel to start 2stroke, so get a front wheel starter, with regen. With current range it should be able to recharge ( please weigh in), 3 or 4 times, as its sole use is on flat ground or arround foot trafic. Any drag coefecient will be nothing to the gas motor and an extra 3 or 4 extra kilos wont be noticed.
Auto companys arent any smarter than us. They have more money and bigger markets. So what.
For ever i've watched youngsters touring in Alaska, rarely taking the more interesting trials or roads less travled. Its a time and energy play. Ive scarsely ever seen midle aged, and Never Older riders. And guess who has more time and $$ to invest, without an option to do so... hmmmmm.
Been up north fifty years, watching in come and go and i'am sure that 300 miles range, with a ten minute stop to refuel n-go cheaply, will intrest many thousands people.
I'am new to e-biking and need help getting hooked up to a proper hub assy. for my needs. Ive got ability to wrench or fab anything though finding suppliers is monumentaly ridicules ( there's no one to call, and IF you can, they only know COMPUTOR), . I only found this site two days ago Sooo , this is the maiden voyage... please let me know what U- think and pass back any advice. Thanks
Olds C0ol
 
Welcome to the forum

I started to do exactly this once, but then math got in the way. I realized it was actually not going to work. your total range would be less than it would be if you never used regen to fill the batteries. The problem is, you don't get something for nothing. It takes roughly twice the energy to generate power to put into the battery as you get from output. And if you're running the bike on a gas motor, then the energy you're putting into the batteries is coming out of the gas tank. Lets say you're cruising along at 20mph, using about half a horsepower on the gas motor (375 watts). When you hit regen, you'll have to throttle up to a full horsepower of output, as the electric motor will now be putting a half horsepower of drag on the bike. So you're now dumping twice as much gas into the motor while it's in regen. Regen isn't that efficient. you have losses at the motor, at the controller, in the batteries. then when you go to use the motor, there will be losses again from the battery, the controller, and the motor. In the end, you will have about half the available energy from the electric motor as you used in the gas motor to charge the electric up.

Also, Regen braking is useful, but a light weight bicycle doesn't have much kinetic energy to convert back to electric power. there isn't much energy to be had there. Ebikes can hope for 5% range gains if they have a lot of stopping.

What might work better for you is just a simple starter motor for the gas motor. BBR makes a pretty cool set up, and I've seen a few 4 stroke setups with electric start, too. https://www.amazon.com/Tuning-Bullet-Electric-Bicycle-Engine/dp/B01LZL1N3P

61OsikGHVhL._SL1100_.jpg
 
How about also adding a sterling engine to turn the heat from the losses back into motive power? Joking :) Kinda viable though, a few high efficiency power stations use it but it's too bulky for mobile. Just a point on that starter motor, some old RD yamahas used the flywheel generator for starting, DC with a commutator in their case but most bikes use a 3 phase alternator, wouldn't take much to drive them with an ESC. Same applies to cars too btw, they have a big heavy DC lump of starter motor rated at about 1.2kw to drive the flywheel for starting and a relatively light and efficient 3 phase alternator to charge the battery that's also rated at around 1.2kw, go figure :/
 
4 stroke motor with a pull starter? They're slightly less obnoxious.

Or move to Florida where there are places to plug in an e-bike, and having a breakdown won't lead to death by hypothermia.
 
You will find some anti gasser folks here, but I'm not one of them. I use gas a lot, but for larger, faster, motorcycles or scooters. Like when I need 200 mile range and would like to get there today.

Perhaps its just time to upgrade your ride. The smaller scooters have similar motor size, and decent enough range, and they are electric start motors. Even the bigger ones, like 150cc, get 70-100 mpg. My 400cc scooter gets worse mileage, but I'm very happy to get 65 mpg, at 65 mph.


I would say that a hub motor just to start the bike sounds like an expensive way to do it. But maybe cheaper than a new 50cc scooter. But like drunkskunk said, it may affect range more than you think to use a DD motor.

This is why, at 5 mph, not regen enabled, a DD motor resists very little. But by 20 mph, its resisting a lot more. So your cost of just rolling with the DD motor on the bike is more than you might have thought. But once you engage regen, it resists a LOT. It might only take 5 min running to get your start power back, but for that 5 min you will be crawling. The regen is that much resistance. And then you have that high drag the whole ride to come with the regen off, unless you ride very slow.

However, you are on a good idea, just using an electric wheel to start the bike. What you will need though, is a non regen capable, geared type front motor. As small as you can get, which usually makes them fairly affordable. It won't regen, so you will have to charge your battery, but it won't resist any either. So your gas range will remain unchanged.

This link is just to show you the type you want. Shop around for a good price delivered to your location.
https://www.ebay.com/itm/36V-Electric-e-Bike-Conversion-Kit-Front-Motor-Hub-Wheel-250W-350W-500W/254215695693?hash=item3b306fad4d:m:mExNIipswV4hfrrmoaMBl3A


Your dilemma will be what to spend on a battery. I think you should buy a small 36v lithium battery, for low weight. But if you go with a lead battery, it can be quite small compared to normal electric bikes. 3 12v sla type batteries, of about 5 ah, won't weigh all that much. And it will start your bike quite a few times before needing a charge.
 
Gas and noise is fine in my books, as long as we can get from point A to point B with the fuzz hassling us.

Assuming you got a chinese bicycle 2 stroke, say a hundred or two bucks you laid down on that.
Why not go with a 500W or 1000W, weight is of no concern, well I guess it is because you want it on the front, so go with a 500W but if the weight is not that much more, then go with the 1000W. You'd want steel fork, and beefy steel torque arms. I just buy 1/4" plate and get the grinder out and use hose clamps. You could do a motor on the rear, but then you gotta figure out your gasser gear mount, not super easy to do on the disc mount neither. Front it is, or mid drive. I'd go with the mid drive myself, like the Bafang 500W, then you'd be styling in the bitter colds of Alaska, year round. But then the direct drive motors are more robust, so now I am thinking a front hub direct drive. Choices.
 
Olds C0ol said:
Can no longer pedel to start 2stroke, so get a front wheel starter, with regen. With current range it should be able to recharge ( please weigh in), 3 or 4 times, as its sole use is on flat ground or arround foot trafic. Any drag coefecient will be nothing to the gas motor and an extra 3 or 4 extra kilos wont be noticed.
Click to expand...
As long as the torque the hubmotor can create is sufficient to pull the bike forward against the resistance of the gas-powered wheel's engine, fast enough to get the gas engine to start, then it should work.

However...a typical controller's regen is only on or off. That may not give you sufficient control over recharging currents to prevent damage to the battery, unless you ensure the regen current of the controller is designed to be lower than whatever the battery's charging current can be. The regen current is usually based on some fraction of the main motor current limit.

If you need more motor current to drive the motor, than would be "allowed" by that, then you may need a cotnroller like some of the ones http://ebikes.ca carries, taht have variable regen. Then you can setup a switch on the handlebars (or wherever) to give you a simple "recharge at this rate" action, after you've used the motor to get started and are now using just the gas engine.


One issue to think about is that the battery (regardless of type) is going to have to be well-insulated whenever the weather is cold; they really don't like to freeze, and they dont' like to be charged when cold either. You may even have to add some way to warm them up before using them under severe conditions.


Another issue to think about is the battery has to be big enough to safely deliver the current the motor controller needs, for long enough to start the engine. RC LiPo can be a very small pack and do this, but it's generally more sensitive to adverse conditions and when stuff goes wrong with it it can be more dramatic than some other types, and it's quality control is...questionable at best. ;) But many people use it just fine, as long as proper care is taken. But there are many kinds of batteries, and it all depends on how much current you end up having to pull from it, for how well any particular one would work for your needs.
 
Amberwolf: thx 4 good input. At gas mtr strtup, i'll have 6- 500f caps in prallel w/batt etc. to handel spike demand, likewise assisting in charge absorbtion . Solar charge controlers/invertors have similar perameters of opperation I'am borrowing tech from... The auto industry hybrids have done it sucessfully 4 yrs. I just need to spook out & balance up whats been done before. Of course an upper & lowr V disconect ( cutout) , to eliminate over charge & fritcion drag will be necessary. So maybe a geared hub w/ modified brake control switch should be considered?! ¿
Mechanical proto, design, fab. for me is easy, alas electric theary, schematic design, is not my cup of grog... please feel free to contact me at
dutchmanent@gmail.com Thx Olds C0ol
 
A geared hub cannot regen. I suggested a geared hub, and just charge when you get there. Geared will not affect your gas range any, so that might work better than a regen setup.

It won't be that big a deal to carry enough battery for a few starts. Lipo would be a good choice for a start only battery, a 2 ah Turnigy pack from Hobby king would start you quite a few times, and still be pretty dang cheap to buy. 10s, two 2000 mha 5s packs in series is 36v 2 ah.
 
dogman dan said:
However, you are on a good idea, just using an electric wheel to start the bike. What you will need though, is a non regen capable, geared type front motor. As small as you can get, which usually makes them fairly affordable. It won't regen, so you will have to charge your battery, but it won't resist any either. So your gas range will remain unchanged.
<snip>

Your dilemma will be what to spend on a battery. I think you should buy a small 36v lithium battery, for low weight. But if you go with a lead battery, it can be quite small compared to normal electric bikes. 3 12v sla type batteries, of about 5 ah, won't weigh all that much. And it will start your bike quite a few times before needing a charge.
Click to expand...

I agree with using a small geared hub motor. For a battery, I think one of these 36 volt hoverboard batteries would be a reasonable option. The one I've linked to is on the expensive side, but you can sometimes find them with name brand cells for $35 to $45. I've used a single one of these to go five miles on my bike. Assuming that a 100 yard run-up should be enough to start the bike, a hoverboard battery like this should be able to get you 17 starts per mile of range and at five miles total range, that equates to about 85 starts on a full charge. But its cold in Alaska and a start accelerates from a stop. It isn't continuous running. So lets just assume about half that number of starts for safety. I'd assume that you'd have an opportunity to recharge before you ever push that limit of perhaps 40 starts.


https://www.ebay.com/itm/Samsung-Self-Balancing-Rechargeable-Battery-fits-6-5-8-10-Six-Months-Warranty/192712985209?_trkparms=ispr%3D1&hash=item2cde96ca79:g:1E8AAOSwXHxb35KH:sc:USPSPriorityMailSmallFlatRateBox!85268!US!-1&enc=AQADAAAB4KX%2FKt4E1xf3SDqEdBclaYbR15HUHkVFV%2FdVddzwofg3RrzIoZ4RssRXjtbb490jJI04yYbuNcFpxgb3oTy7LLF9fTKrQ1T9dM%2B1xcb14taXr%2BK9uWj4TunTXHDg8XZNU9l5WmPp0v%2BJ4O4YUel26xEsCI69L3ffkKhvD%2B52Pkm6nKTHDXI9C%2BEUsnEa5ZrymSxH8a90JvvPYkJiRdPkDt7Srtv%2BlqCTWAAiHywZGIFxtPYWpn2huwpoGoI4IQb53tQ%2ByluZvhxKoGDKOoGBAKo9BYRtCY6WFr4BRb5c5T9tATPLHoY3sRTD0UeqbC%2FM1Jz3MTKNDMT%2FTPVIGUp5SAo7DijFB8vNtRtaTJqYVZ7cokvvq4y6XqpER56yaXJZbdZ8toFPhS%2BqCWFYeqF7oA1%2FUtPmoWnHnRVfodunRPsXCGXdTE41h3N8vefbAy%2FDazntWHbOykJelIFvjhwyOkIDaRuWpC%2BQP4mcBU3B9lVsfoXTOu%2FhuzGVa9LuOnKwKOQGcXIfwfbOf1E0jfuvSFdeVpmCbbIyha1Hz2tefCdvyQTixXjuVZa2FlOE5jiCd%2FTzQc3WOHPKcbno9hNvh4y1BrUeYyyqu1pHsFYd%2FE34i0LZL9LtZDpMqeZTIymMhg%3D%3D&checksum=192712985209accb519177204020b1136ad7d468cebf
 
No need for electrics for those whom got their licenses snatched from them for whatever reason. Even DUI'ers can roll with fumes legally in FLA.

Chalo said:
4 stroke motor with a pull starter? They're slightly less obnoxious.

Or move to Florida where there are places to plug in an e-bike, and having a breakdown won't lead to death by hypothermia.
Click to expand...
 
Well, we drove him off like a heretic long ago. But he lives in Alaska anyway. FWIW, he'd be illegal riding anything with any kind of motor in New Mexico without a drivers license. It just varies from state to state. Right now in Albuquerque, they are finding out about how you can get DUI's on those shared scooters. :lol:
 
dogman dan said:
Well, we drove him off like a heretic long ago. But he lives in Alaska anyway. FWIW, he'd be illegal riding anything with any kind of motor in New Mexico without a drivers license. <snip>
Click to expand...

It seems like NM is ripe for change since their DMV is (as of the PDF below) not treating motorized bicycles as mopeds. This does put the rider in a gray zone since by law their motorized bicycle is a moped. Especially with no clear definition of what a motorized bicycle is.. But in the meantime the states vehicle law enforcement division is saying they aren't going to abide by the law. Having a copy of this PDF would seem to give you a strong defense against any stiff penalties if it came to a court case or when talking to a cop - especially if you've been riding in the manner of a bicycle and at bicycle-like speeds. But mostly, I'd think sending this publication to the legislature might light the necessary fire to get them to pass a law that their MVD would be willing to enforce.

Section E. Motorized Bicycles
Revised November 30, 2017

Motorized Bicycles are not considered to be mopeds or motorcycles.

By current NM MVD practice, motorized bicycles are considered to be bicycles (not mopeds or motorcycles) and are not subject to the titling and registration requirements of the Motor Vehicle Code.
Click to expand...

http://www.mvd.newmexico.gov/vehicle-procedures-manual.aspx?1f7fcb5548ee4e17a47ff4e27e571a01blogPostId=ec45f29f43944fb8a848cd27a012a8b1#/18e
 
You must log in or register to reply here.
Back
Top