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motorbiker · #11 (**permalink**) 08-07-2009, 03:35 PM

Interesting thread. I like the lawnmower wheel idea. I am going to have to find an electric scooter motor.

deacon · #12 (**permalink**) 08-07-2009, 07:37 PM

For some reason known only to god and the usps, my sprocket went back to California. Why I have no idea. It should be back here again middle of the week and I can try to make the wheel work. In the meantime the one with the scooter rear wheel is humming right along. I like it better everyday. Except for about an hour today when the rear bike wheel tossed it's sprocket for some reason. The reason is that the retainer came off on it's own accord. I went up to the thrift shop and bought another junker for four bucks. I got a front wheel, a back wheel, and a set of training wheels for my grandson's bike. Not to mention the chain. Some junker will most likely get the rest.

Motorbiker I wouldn't get a scooter motor smaller then 350 watts. It seems to be a really good size for one of these little bikes. For me the 20" kids bike makes the best platform.

deacon · #13 (**permalink**) 08-08-2009, 06:48 PM

I checked online and the expected delivery date for my sprocket is now next friday. Since I have nothing to do till then, I went savaging in my old parts box. I found a small 11 tooth sprocket. That would make it a one to one ratio so I put together a drive using it. The down side is that the bore is 5/16 not 3/8 like the one on order. I had a couple of skate board bearings left over from a previous attempt at this project. So I put together a frame using them the 1/1 sprocket and an old drive wheel of under three inches in diameter. That would still be at least a 2/1 ratio. I also gorilla glued a piece of sandpaper to the smooth drive.

This sounds foolish I know but it is exactly the same design as the 3/8 drive. It will give me a chance to work out some of the bugs before I build the bigger one. Tomorrow is a 'lot of family' day, so I might get a little done but I'm not counting on it. Right now the question to be answered is where to mount the motor on the drive unit.

This particular type motor mount I have been using hangs if off the drive axle. On this one there is no reason for that to be the case. On the mount as is, it hangs to the side of the actual drive unit. I would kind of like to mount it so that the weight is over the tire on this build. I am hoping to be able to do that. Only time will tell, but there is hope since the welding has taken a quantum leap in quality.

deacon · #14 (**permalink**) 08-09-2009, 08:45 PM

I finally got the pint sized version of my diy drive completed. Well once I weld the hinge on it is complete. Of course then I have to mount it. I never could get the skateboard bearings to hold in place on the frame so I made some steel bushings for the test drive. if I have trouble with the real one and the bearings I got from ebay, I plan to make brass bushings for the frame. If after all my testing the bike doesn't do really well, then I will buy the rear wheel from a scooter and just made a more powerful version of the bike I have now. I like it just fine.

I am more or less playing around now.

deacon · #15 (**permalink**) 08-10-2009, 06:58 PM

I had a huge failure today with the diy drive I was building but I stayed with it and have the beginnings of an inexpensive drive we can all build. I am using skateboard bearings on the small test model and so far after a few missteps it look promising. If the drive works with these bearings there is no reason I can't build one using a kick scooter wheel as the drive and the bearings from it as well.

On ebay i could get the makings of four drive wheels and bearing for under twenty bucks. The kick scooter wheel is 100mm almost four inches. It uses a 5/16 axle probably. If so then an 11tooth sprocket will work on it. I have one on the one I am test building now. That gives the motor a one to one ratio then a 4to1 or so on the drive wheel. That would make the wheel turning at about 700 rpm more or less. I have no idea what speed that would be but probably at least 10 to 15 mph.

deacon · #16 (**permalink**) 08-11-2009, 01:12 PM

I tested the test drive I built from scratch. It actually works but there is a lot of drag or something. The bike runs way too slowly. I decided to put that part of the project on hold. I ordered another scooter wheel to just sit on top of the rear wheel of a bike. That is the easiest friction drive I have ever seen. It also works very well.

I have decided to switch my bikes from the pusher back to friction drive. It is a heck of a lot easier to keep adjusted. Also easier to move in and out of the shop. I don't really need the extra speed of the pusher to be honest.

deacon · #17 (**permalink**) 08-11-2009, 06:48 PM

I couldn't stand it, I had to go back and try to fix that lawn mower wheel drive. It isn't quite straight but I have it mounted and I'm going to give it a shot. It has the small sprocket, a one to one with the engine, so it should be interesting if it doesn't fly apart.

It's just an experiment since I have a real scooter wheel coming which I can use as a drive for the friction drive. It is pretty big, eight inches actually, so it looks funny. But heck who cares, I guess.

I am already using one of those so I know it works. I think I am going back to plan "A" and mount the 18 tooth sprocket on the motor. That should increase the output by about 50 percent I guess. I just can't leave well enough alone.

deacon · #18 (**permalink**) 08-12-2009, 01:14 PM

I think i whipped that lawnmower wheel drive. I have it on the bike but of course it's raining. I think I have the bearings so that they won't bind. I have the wheel itself true now. That just took a night to think on the problem. I tried it using a couple of 3/8 inch nuts that look like acorns. The nylon keeper on top slips right into the wheel's 1/2" opening then when I tightened it the nut just pushed right in evenly. I used on on the other end as well but it didn't push in it just got tight. How long that will hold is anyone's guess. First clear day or if the roads dry off I will give it a try.

deacon · #19 (**permalink**) 08-12-2009, 05:49 PM

bear in mind I haven't tested this yet but here is how it looks ready for testing....[IMG]

[/IMG]

deacon · #20 (**permalink**) 08-12-2009, 05:50 PM

By the way I am still learning as I go... I discovered that if you cut the bearing cups off an old bike front wheel they will work as holders for sealed bearing. One can weld those holders to the frame. I wish I had figured that out sooner.