First Build friction drive

[Elmo]

Starting my first build. Gonna use a friction drive. I have a 30CC Homelite weedeater engine that is in good shape. When I got the enjine I had to replace the fuel lines as they were dry and both were broken.
The bike is one that I built from old bike frames and I have a bottom bracket in the right place to use as a pivoting mount for the engine.
Elmo

 

[Elmo]

This is my motor mount. Cut from a piece of 3/8" aluminum plate and a spare crank arm. I had it welded together at a cost of $15.00.

 

[Elmo]

Motor mounted on bike.

 

[NEAT TIMES]

Elmo, Welcome To The Forum. That Is One Solid Motor Mount. Are You Going To Have A Drive Roller Support On The Other Crank Arm?? Did You Cut The 3/8 Plate By Hand?? That Should Be A Sturdy, Trouble Free Mount. Great Thinking. A Bicycle Built For Two Frame. Now It`s A Stretch Limo!! Lol. Very Cool. Keep The Pictures Coming. Very Interesting. Ron .

 

[NEAT TIMES]

You Built The Frame. Better Yet. The Dog Seems Comfortable With The Plan. Lol.

 

[Elmo]

Elmo, Welcome To The Forum. That Is One Solid Motor Mount. Are You Going To Have A Drive Roller Support On The Other Crank Arm?? Did You Cut The 3/8 Plate By Hand?? That Should Be A Sturdy, Trouble Free Mount. Great Thinking. A Bicycle Built For Two Frame. Now It`s A Stretch Limo!! Lol. Very Cool. Keep The Pictures Coming. Very Interesting. Ron .

I cut the plate with a jigsaw w/metal cutting blade. Piece of cake except for the aluminum chips everywhere. I havent figured out how to incorporate a roller support yet. The other crank arm is to engage/disengage the motor with the tire. Thanks for the reply.
Elmo (not the furry red one)

 

[NEAT TIMES]

Elmo, Your System Could Be Used Above The Rear Wheel In The Normal Behind The Seat Position Also. I Think You Will Inspire More Economy Builds With Wacker Engines. Cooool . Ron .

 

[Elmo]

Got my friction roller done today. I used a black iron 1/2" pipe cap and nipple. A friend of mine, Mike, trued up the cap on his lathe and drilled and tapped the cap for 5/16"X24 threads so it would screw on the weedeater output shaft. I put it on the motor and hooked up a spring to hold it against the tire. The rope in the pic is a temporary way to lift the roller of the tire. Hooked up a throttle linkage with an old friction gear lever. tried to ride it and made about 100 feet before the roller began to slip RAIN. Folks sure know what their talking about with wet and friction drives. Slip city. I threw in a pic of mikes ride, nice and fast. Mike wants to build a bike.
Elmo (not the red furry one)

 

[NEAT TIMES]

Elmo, Way To Go. Maybe Mike Can Knurl (knurling Tool On Lathe) your Drive Roller, For More Traction On The Tire. Ron

 

[NEAT TIMES]

Mikes Rod Is A Beauty. Ron

 

[NEAT TIMES]

Elmo, I Have Friction Drives, They All Are Centrifical Clutch Set Ups. I Was Thinking About Your Roller Set Up. With Mike And The Lathe, You Are In Good Shape. But On "staton-inc" Under Their Friction Drive Kits, About Page 2 Or Three The Have Drive Rollers Of Different Size. They Are Solid, No Center Hole. Mike Could Modify Them To Attach To Your Engine. Maybe Even Rig A Support Bearing Or Bushing On The Other Side. That Would Make It Bullit Proof And Take The Strain Off Your Flywheel Etc. Just A Thought. Your Motor Mount With The Crank Arms And Bottom Bracket Is About The Slickest, Strongest, Cheapest I Have Seen! Great Improvising. Ron

 

[NEAT TIMES]

Another Thought, Is Your Spring Pulling The Roller At Least 1/8" Into The Tire? The Tire Should Be Aired Up Fairly Hard. Just Trying To Help. Ron

 

[Elmo]

Thanks for the good words Ron. I may have the tire too hard (80 psi). Thats the way I always rode, the harder the tire the easier it is to pedal. The tire is rated for 85 psi. Guess I will have to learn some new ways because motor assist is some different than human power only. I have some things to try to make the roller have more friction. I do not think that I had quite enough pressure on the wheel as you said, my spring is not quite strong enough. BTY mike couldn't find his knurling this morning, his tools were kinda messed up because he had just gotten another lathe and alot more stuff. I really appreciate your advice.
Elmo (not the red furry one)

 

[Elmo]

Well I am down for a while. The flywheel nut got loose somehow and it is toast. I think I know where there are a couple of engines like mine that may have salvage parts.
Elmo

 

[NEAT TIMES]

Elmo, I `ve Been By The Mailbox Waiting To Wave At You As You Spead Past!! Lol.. Bummer!! Do You Think Your Roller Needed A Washer Of Spacer Under It To Hold The Flywheel Against The Taper On The Crankshaft?? That Just Does Not Seem Right. Keep Us Posted, Please. That Is Such A Solid Set Up. You May Not Be Furry, But You Must Be Red Now!! "git Er Done" Later Buddy Ron .

 

[Elmo]

Elmo, I `ve Been By The Mailbox Waiting To Wave At You As You Spead Past!! Lol.. Bummer!! Do You Think Your Roller Needed A Washer Of Spacer Under It To Hold The Flywheel Against The Taper On The Crankshaft?? That Just Does Not Seem Right. Keep Us Posted, Please. That Is Such A Solid Set Up. You May Not Be Furry, But You Must Be Red Now!! "git Er Done" Later Buddy Ron .

Ron
The threads in the pipe cap were not strong enough and pulled out. I can put on a grade 8 nut or use a stainless cap that mike had. The good news that I have 4 more 30 CC homelite weedeaters that I was given. One seems to have real good compression. I should be able to at least come up with one good engine out of the whole bunch.
Elmo

 

[NEAT TIMES]

Elmo, 4 Free Wacker Motors!! You Are Living Rite. I Could Only Fined Two For You On Ebay, And That Covers The World. Lol. "it Won`t Be Long Now" Ron

 

[Elmo]

Well out of those four engines i finally was able to get 1 good running motor together. It took a lot of swapping parts and trial and error. Mike is going to bring the bike Friday so I can get back to working on it.
Elmo

 

[Tom Bartlett]

Elmo,
Keep up the good work. We (ZipCycle) used the 25cc Homelite engines on over 2,000 friction-drive bikes and found the engines to be very reliable. We recommended a rear tire pressure of 45 lbs (26X2.125 tire). And Neat Times is correct, make sure you are pressing the roller at leat 1/8" into the tire. With a polyurethane roller (ex-skateboard) we were able to ride in the rain (but not through deep water). Tom Bartlett

 

[NEAT TIMES]

Tom, Great To Hear You Are From "zipcycle", A Connected Person. I Have One. Have Not Got It Running Yet. The Drive Roller Was Wore Almost Square, I Suppose They Let It Rub On Tire When Motor Was Not Turning Over. A Nice Set Up. This One Has 334 Miles On The Speedo. I Converted The Jack Shaft To Half Inch And Have A 2" Drive Roller, I Think The Original Roller Was More Like 2 1/2" Dia. Now Bmp Has A 2 1/2" Drive Roller. I Will Post Pics. I Have The Motor Covers Off, So It Is Not Looking As Good As Possible. I Think Its Missing The Left Side Motor Cover. Have Had The Covers Off Over A Year. Zipcycle Web Site Was Still Working, A Month Or So Ago. Tom, I Think Its Cool You Joined The Forum. Hoping To Hear More From You. Ron