why I love friction drive

Like I have posted in the past there was a guy in Europe with an 8hp vertical shaft lawnmower engine driving the side wall, it seemed pretty much unstoppable as far as what it could climb!
 
We may see this one is wearing me out. With the ebike it ran out of juice about the same time i did. this one I get to ride more so it pushes me more. I need that.

Since I know I can do a lift even if i have to use a real lever to raise the engine, that part is solved. there was never any issue with the throttle except how much junk I could fit on a handle bar set. I think one speed is about that best idea for a friction drive.

So you need room for one brake lever for your front wheel emergency brake if nothing else.

Some kind of shifter or something like that for a throttle...

I have a feeling the motor lift lever will have to be mounted on the top rail of the bike and activated with the full pull of the hand, not just the grip of a brake lever, at least for me.

There may be benefit in doing it that way. I want to experiment with a rod moving front and back at the henge fulcrum to either tension or lift the motor.

Those are basically all the controls I have on this bike and all I think I would need on a bigger one.
 
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Yeah 40cc or so sounds about right.definitely somewhere over the 31 of a ryobi and around the 42cc of a chainsaw. I love the drive roller attachment concept. It is really ideal for a friction drive set up. It is very easy and secure to mount all kinds of things to this engine.
 
I picked up a hard rubber bushing to try. It was okay, but not any better than the metal drive wheels. The metal one won't wear out so I am trying one more tomorrow. The 1/2 nuts are too small they sing, the 3/4 will bog down now and then, so I'm trying 5/8 tomorrow.. If it is just right, I'm going to call it my goldylocks drive.
 
I have spent three days running up and down the road. I have determined that the best drive roller I have is three 5/8 hex nuts attached to the motor. I have no idea what the outside dimension is but the 3/4 chokes at the top end and the 1/2 whines at all speeds, so I have to say the 5/8 did the best.

I have a rubber bushing I tried that is about 3/4 inch and it was okay but not really any better than the hex nuts. So I guess I will stay with them for a while. I have a working lift clutch. a throttle that works really well finally, a drive roller I like, and the motor runs pretty good. I guess i'm going to have to test the bike in different situations to determine it's value to me.

The combination as it is now will pull several hills on my path without any help. Not real fast but it gets up there. The ones that require help don't require much so I'm going to run some real life test this weekend. The traffic is down in front of my house on Sunday so I'm going to run the bike a mile or so to the shopping center, then a couple of miles to the mall. I have already run it to the hardware store so I'm pretty sure it is going to work just fine now, but I want to know how it does on those hills.
 
Would have never thought of using nuts, how smooth are they? Have you tried aligning them with the points of the hexs staggered? I might have to get my Bumble Bike unit back out, it worked pretty well stock.
 
They are pertectly smooth except for the corners. I tried to stagger them some but here is the problem I had which I only worked out at the end. Trying to keep the nuts lined up exactly so the drive didn't wobble was difficult. then I found out I could take a 5/16 nut and drive it into the threads of the 5/8 and it would keep the bolt centered and the nuts lined up. So now I can do just eactly why you mention. I expect that I will try that the next time I have to pull the drive wheel for any reason.

On that stock engine how big is the roller and what is it made of. When mine arrived it was a rubber bushing 3/4 " in diameter. The motor whined alot because it wasn't working a lot of the time, it was just skipping. I think. This is the best I have found for sounding like it is pulling at even the high end. Maybe not all the way to the top but a lot closer. It will also pull my fat butt up most of the hills around here on it's own. The others are easy to assist the bike up the hill.

Now I wonder when I will ever ride that ebike again... I love the torque of it but I hate the range and the weight. I think I will keep it though just to have something around for the kids to ride. Matter of fact my oldest grand daughter needs a hobby lol....
 
The stock Bumble Bike roller is knurled steel 1" dia. The roller on the Hongdo Solex is a segmented drum probably 42mm. I never slips or skips. You can kill the motor with the brake. That little motor is pretty amazing, has a lot of torque. Its top rpm I imagine is close to a china girl idle. When you come to a hill it just loads up and chugs up the hill. I keep waiting for it to stall but it never does. Its roller equates to 1.6" which is necessary since it does not have near the rpms of the Bumble Bike. Whats your top speed?
 
I honestly haven't figure it yet. I have had it on the two test areas so far. They are both up and down hills. I know that down hill it will fly. It keeps pulling even when it is coasting full out. On the flat i think under twenty but close. Up hill like you said it wants to slow to a crawl. I have not had it stall yet but it does get close and I just pedal it a few times and it goes again.

The bike will also shut down with the brakes, but I prefer to lift the engine to keep it going. I don't like to drag start this little motors. I still can't quite figure out what the size is compared to what I have built before. I'm sure it's better than the 31cc ryobi and if not the same close to the 42cc chainsaw I had a while.

I think the nuts are the best on the knobby tires. I could be wrong and they could beat the knobs off the tires but I'll just have to see what it does.. The bike is actually great fun to ride so far. My big complaint now is the size of the gas tank. I had to replace the one that came on it with an even smaller weedeater tank. I swear i think it holds about a cup of gas. I have a couple of bottles I can carry extra but I'm going to have to check it often.

What is really humorous is that I built it to replace the ebike which I can only get about 3 miles range with my standard set of batteries. And this bike will only get about 3 miles on a tank of gas. The difference is that I can carry a lot of gas for a lot less space, weight, and money, than I could carry comparable batteries.
 
The carb is a pumper it will pull fuel from a reasonable distance. Make a seat post tank as others have done. Use a large tin can, get an old mower tank or just about any thing else that is gas proof and easy to mount.
 
Yeah I have made them out of about anything at one time or another, I liked my propane tank one. Oh by the way when I put the bike away at lunch, I was almost out of gas, so I thought I would fill it up before I left so I wouldn't forget. Bad idea. It spurted gas from the tank once I opened the top. It was obviously under some pressure.

Also I have a lift on my motor so I found today that I can run it with the full tension to gain speed on flats and down hill then lift it a hair to deep it from bogging down so badly going up hill. The drive wheel is eating up those knobby tires. I have to find a better way. I think that is because so little of the tire is in contact with the roller. I think I need a different kind of tire and when these are gone, I'm going to buy some street tread tires.
 
I processed your info and used my old tube cutter to make a smooth drive wheel about an inch in diameter, od that is. It has just a tiny bit of texture. So I put it on and gave it a try. I does just as well as all the nuts and bolt and stuff.

What does the most good is the lift clutch. I can drop it slowly and let it work up to max speed which is pretty good because it has way more tension than it should have, if I couldn't let it off a little. So when i get it full out, it is probably over twenty but only a hair. Then when I hit a hill it bleeds off speed slowly. On the hills that are longer than two blocks it can get right hinky without the lift. I take just a little tension off and it will crawl up. When it gets to the point that even that is loading up dangerously, I take a little more off and pedal a few times.

There is one hill that is killer because it is just about five blocks long. Slow incline at first just enough to drain the speed, then it get real steep and nasty. For that I did the pedal thing and I got up it fine. I have had to get off bikes and walk them up that last half block, so I consider this bike a success.

I also ran it down to the shopping center and got it up the steep hill coming home, so that makes it a winner. I have had the bike to the hardware store and gotten it home, so that was a winner. I took it to the mall this morning and got it home just fine so that one is a winner as well. I have had to relearn to use the lift clutch effectively, when approaching a stop sign.

I lift the motor and coast up to it. Going slow enough to stop if need be but still moving enough to kick the pedals and drop the motor if I can. That has been working pretty well today. I hate to start any of these bikes from a stop sign, especially in traffic. If I have to, the Ebikes are the best for that. They will actually help you with that first turn of the pedal. That's the one that makes me wobble on an incline,
 
Glad it is working out well. The street tread tires will probably be even more grippy than the knobbies due to contact area. I can raise my Solex on the hills with the handle but it doesnt help. It is more of a torque motor so it is best left to chug on up. There is only one hill around, and its a monster, when climbing that one I will give it a few pedal strokes out of sympathy.
 
Mine seems to be more about the friction on the wheel than the torque of the motor. Did you notice that about your bee. Too bad there aren't more of us on the friction drive path to eternal harmony and happiness.

Oh year about the knobbies, I think the big problem and I'm not sure is that the knobs tend to go quickly then all you have is the thin layer of rubber before you are in the fabric of the tire. I am going to put one more knobby on I expect before the road tires arrive. With the full smooth roller, i want to see what it does to them.
 
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In theory the smooth roller on a smooth tire has the best bite, until you ad water that is. In all honesty I have not used the Bee for the last 25+ years. I actually drove to Havana Fla. when I was down that way and picked it up at the "factory" in 1980 I believe. It worked well but the bike it was on had a badly out of true wheel. So I put it aside to fix later and never did. My other 3 bikes are chain or belt drive. The Solex is my only friction drive and I love it. But you have to understand the design and its form of operation. They are just relaxed easy fun.
 
ah but there is a harmony with the bike that I never had with the faster chain drive I built. The china kit bike had a great look and ever since. the friction drives always looks as they they have a tumor but there is something about the peacefulness and the ability to make eye contact with the people looking at you go by that the china bike couldn't match.

It's just a fun ride for me. I went back to the noise of gas so i could ride more than i could with the quickly power starved ebike, but I loved it as well. I don't know that if more people tried the friction drive more wouldn't find it enjoyable. At least that is my feeling, but then I don't have to ride the bike anywhere it is all for fun.
 
You are right the simplicty is in the power transmission, it is all direct and quiet. Apparently the ratio is a basic number of the universe, keep the roller size the same and you can drive a wheel the size of the circumference of the earth at 20 mph. I rode my Whizzer @ 45 mph today and it was a rush the scenery was blured and the speed was cool. I rode the Solex on the same route and it was just as cool, what I traded off in speed I gained in interaction with the surroundings. Earlier in the day I rode to a breakfast meeting on the interstate on one of my motorcycles@ 70+ I enjoyed that as well, but knocking through the country side at 20mph is a gift.
 
In my case I have done all the driving at 60 I ever plan to do. I drove all manner of things over my 65 years. I'm one of the few people, who still have their driver's license, and the ability to buy a vehicle that will do the speed limit, but who know when to quit. I have a brother in law who is a threat to himself and everyone else he passes on the road, but he insist on driving still.

I quit when my doctor and wife told me they would call the highway patrol, if I kept on driving. Turns out once I got the bikes going, I never really missed the running all over hades on a whim. Now if I go somewhere it is with the wife, which is a lot more fun than it sounds, or it's a trip on my bike, Which I have planned out well in advance. Those little trips are all about geography, so planning them is a huge part of the fun. It's a lot like leading a wagon train out west. You have to avoid the mountains and the rivers until you find just the right place to cross.

I had no idea who my neighbors were, unless they lived beside me or their kids had bikes I worked on, now I know them by sight at least. They mostly smile when I go by, so yeah I gave up a lot of freedom. I don't really miss the smooth 60mph images I gave up because I traded them for a life with a lot more texture.
 
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Yeah I agree, I have been slowly winding down. I sold my last airplane 2yrs ago and basically gave up flying. Sold off the crotch rockets as older reflexes are slow and the body doesnt heal like it used to. So I am down to a 72 VW, a boat , a couple of cruiser motorcycles and 4 motorbikes. Seems like we revert back some times to what first really caught our attention when young. For me it was a kid down the street that got a Puch/Allstate moped, imagine having something with a motor! Ever since, anything with a motor and 2 wheels has lit my fire. Am really enjoying building motorbikes, they are realitively cheap to do, fun to build and useful when done. Cant stop building em! O well I digress. Yeah friction drive is cool, it like flying a low power aircraft, you plan your moves carefully!
 
My first motorbike wasn't quite a motorcycle. It was a 109cc sears bike. It was an oversized moped but had to be licensed as a motorcylce. I was 22 and back from an asian vacation that was a big vacation spot for young men at the time.

I wanted to do something cool and I saw the 'then came bronson' tv show. So I decided to take the bike and ride to atlanta. Even then it had to be planned carefully, because top speed, if not going downhill,
was well under the interstate minimum speed limit.

It took me two days on the road each way, but it was a blast. A couple of great stories came from it. Including being cornered by a south carolina highway patrolman in a diner on the morning of the last day on the road. He gave me some really good advice though, get the heck of so SC and don't every come back. I've had bigger bikes since, but its like women, there only one first time.
 
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