HOW-TO mount weed eater engine on bikes the easy way, no welding

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sscustoms

New Member
Mar 13, 2011
29
0
0
australia
hi everybody so arfter build my 1st motorised 26c bmx ,just today i took it for a lil spin the thing is not tuned so its hard to start and run but was suprised on the torque of it im and 19- 6ft3 86kg and it moved me with is say qautre throttle ,anyway i have found a salouting for people of dont have welders it involves angle iron and u-bolts is set my bike up for bout $30 or more in the build
please watch the video and find out more

YouTube - S&Scustoms .how to mount any 25cc,30cc ,32cc etc whipper snipper engine on a push bike
 

deacon

minor bike philosopher
Jan 15, 2008
8,114
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north carolina
the biggest killer of the small engines on these bikes in my experience is vibrations. As long as they are kept to a minimum you are in good shape.
 

sscustoms

New Member
Mar 13, 2011
29
0
0
australia
the biggest killer of the small engines on these bikes in my experience is vibrations. As long as they are kept to a minimum you are in good shape.
,yeah i was woried bout that when i built my 26cc but iv found if you do things right you in good shape plus rubber or leather works great hardley any vibration on the 26cc thanks to some old leather belt pieces neah the u-bolts

cheers sam
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
63
up north now
You also have to strike a balance between just enough pressure and too much pressure on your shaft to tire interface. Too much pressure will load the shaft too much and kill the bearings.
 

sscustoms

New Member
Mar 13, 2011
29
0
0
australia
You also have to strike a balance between just enough pressure and too much pressure on your shaft to tire interface. Too much pressure will load the shaft too much and kill the bearings.
yeah i dont want to bend the shaft still need to ajust my tire pressure
 

deacon

minor bike philosopher
Jan 15, 2008
8,114
9
0
north carolina
I use a spring and turn buckle for my shaft pressure. As Joe just said, I have experience with broken shafts. That is one thing I like about the heavy engine I have now on the Bam bike it has a big drive shaft. Also I like the chain drive bike with the wheel on a wheel. There is no pressure on the small engine I use on it. The pressure is on the scooter wheel on top of the rear wheel of the bike not the motor. It should last a lot longer that way.

On that wheel on a wheel, I bet it would be easy to mount a sprocket on that tube coming off the flywheel nut on a weed eater motor. I bet i would be very easy to do it on a ryobi engine for sure it has a threaded drive shaft that is longer than most of them. If and when the one I have now goes, I will be doing that I'm sure. I expect one could cut threads onto that tube and just hold a sprocket on with nuts and lock washers. That's how my sprocket is held onto the bumblebee bike motor.
 
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voc

New Member
Nov 7, 2013
1
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0
west virginia
Thats a cool build i 2 have just created my first 2 motorized mountain bicycles
here is a video of it and a link to a site Ive made describing the builds and other ideas. Have a look they may help you build yours. There is a simple version and a more advanced one with a clutch so it works more like a motor cycle.
youtube look around on my page fore videos and look at site for details.

http://diymotorizedbike.tk/

http://www.youtube.com/watch?v=5Om26quPG3I
http://www.youtube.com/watch?v=vsnO0MSOI7U

Have a nice day http://motorbicycling.com/images/smilies/cs.gif
 

a_dam

New Member
Feb 21, 2009
351
0
0
Momence, IL
I wouldn't consider a design without an "outboard" bearing on the end of the shaft. It not only takes almost all the radial stress off of the motor bearings, but it eliminates the risk of bending the shaft.

If your design has a friction drive with a pivoting mount, hitting bumps in the road will put a big stress on the shaft; the force will be much greater than the normal spring pressure you use to keep the drive roller from slipping.

It takes little extra fabrication to add the outboard bearing setup to a pivoting motor-mounted-on-a-plate design, and it makes the structure rock-solid.