weed eater bike questions

deacon · #1 (**permalink**) 04-05-2008, 12:12 PM

No not the bike that runs off into the field, but the bike that is made from a weed eater type engine. I know this is going to be a high guest read thread because it is so hard to find any information on them. I have looked and it really is a jump all over the net for bits and pieces of information.

So I decided to start this thread and see who shows up.

First question is, okay I have a couple of weed eater engines on the way. The one i bought on ebay I found out has finally been shipped today. One of the members here has kindly sent me an old weed eater of his that matches my motor to fix or use for parts. Thank you again Joe.

Now here is my FIRST QUESTION

I know the engine had a square hole in the drive shaft to receive the flex cable from the weed eater cutting head. Now what exactly holds the end of the cable securely to the engine.

I think I have the design for the mount pretty much in my head, it is the same as for the electric motors more or less. It's just how to attach the drive wheel that has me wondering.

Big Joe · #2 (**permalink**) 04-05-2008, 12:26 PM

Deacon
There is a screw that holds the shaft (hollow tube the cable is in) into the housing of the clutch. These tubes are apprx 2 ft in length. (too long for box engine is in) I will save these until you are sure you do not need them.

deacon · #3 (**permalink**) 04-05-2008, 04:24 PM

Okay but I'm sure I can rig something. I have seen the drive wheel mounted right up on the end of the engine. The centrifical clutch was still there so somehow the bolted the wheel to the clutch. I'mn just gonna have to see it to know how to work it. thanks for saving it. I might need you to tell me what it looks like later when i start attaching the drive wheel.

deacon · #4 (**permalink**) 04-06-2008, 02:11 PM

Ive been chewing this over and here is the mount I designed

it is a flat mending strip attached to the bike, then a strap gate henge attached to that on one side, then an "L" bracket as a lift handle.

http://i25.tinypic.com/hun1c1.jpg. I might have to add a platform onto the henge to hold the motor.

I think it has a square box on the end of the clutch. I can imagine fitting a nut in there and drilling a hole through the housing and the nut for a pin. then having three nuts welded together to make a holder for the drive wheel.

A simple screen door type spring to keep the tension on the tire.

That should do it. At least I think so. With a little luck it will be the ultimate simple inexpensive motor bike.

elegant in it's simplicity...

**Bikeguy Joe** · #5 (**permalink**) 04-06-2008, 07:19 PM

Ace hardware has a massive spring collection/assortment if there is one near you.

deacon · #6 (**permalink**) 04-07-2008, 09:20 AM

Good to know I am going to need some small ones for the throttle return Im sure.

deacon · #7 (**permalink**) 04-07-2008, 12:40 PM

Engine arrived from the ebay dealer, now I need to know which way a ryobi 31cc engine turns when it is running... If I am looking at the fly wheel does it turn clockwise or counter clockwise when it is runing. I have a feeling it is counter clockwise but im not at all sure.

It seems it should run counter clockwise but that is just a guess based on lawn mowers I have had.

Big Joe · #8 (**permalink**) 04-07-2008, 03:23 PM

Deacon. The engine I shipped has the rope still attached. Just pull the rope and look at the cable housing (you can see it) Or just stick the cable in the hole and pull rope.

deacon · #9 (**permalink**) 04-07-2008, 04:29 PM

I got the one from ebay to start. I don't have a gas tank hooked up yet so I couldn't keep it running but it ran on the gas i poured down the spark plug hole. It is going to be an easy build I think.

There are threads on the Ryobi drive shaft. the are 3/8 inch 32 threads. If I am not terribly mistaken the foot pegs on some trick bikes have a 3/8 32 female opening. It should just screw on. The only problem I see is the threads require a clockwise turn and the engine turns counter clockwise. Sounds like a job for lock tight or jb weld on the threads of the peg.

I have decided to run a cable from a brake handle to the bracket to lift the engine off the tire from the handlebars. If that works this will be one sweet build. Of course it wont lol.

deacon · #10 (**permalink**) 04-07-2008, 08:15 PM

Now I need advice. I have the motor started once.. so I'm good there for now... I had my neighbor weld the bracket so I'm good there. I can't mount things till My new wheels get here but,, I need some advice...

The bracket is a large henged L ... So now how do I attach the engine (had no mounting holes since it was hand held as a trimmer...

I'm thinking to get it set as flat as possible... shim it in place then put a band of some kind to hold it. Maybe a cable with a spring for tension to hold it flat on the frame. I am open to a better idea...