New Build

DavidCP

Member
Dec 28, 2017
34
8
8
28
Going to do my first quasi-test run on the new motorized bicycle design. Not actually riding it but letting the engine run outside to see how it reacts. As you can tell by the abundance of scratches and scuff marks, I had a very hard time getting this design set up. I ended up having to use two laser levels to pull it off and there was only a one centimeter margin for error. I plan on painting over the scratch marks to help hide them but.... beginners mistakes I suppose.

Considering how carefully I plan on riding it, the engine may be highly overpowered for this design but.... all well. 95% of the roads here in town are 15 MPH speed limit roads so this design was intended for a ton of torque.

 
  • Like
Reactions: stock762

DavidCP

Member
Dec 28, 2017
34
8
8
28
Well first test run was done. Immediately seized the engine and broke the back sprocket adapter. After almost $3K of trial and error + 8 months of tinkering, i'm throwing in the towel. It seems I am incapable of making this work. At least I learned a lot about engines in the process.

I have no words to describe how incredibly upset I am. :-(
 

crassius

Well-Known Member
Sep 30, 2012
4,032
157
63
USA
not sure why you had all the problems, but it appears you have the shifter cable trapped under the front mount, also if there is a gap between front of motor and frame, the force of the running motor may spread the two halves of the motor apart a bit causing a loss of compression there, and carb may be at too much of an angle to properly fill the bowl which can make it lean enough to overheat

don't worry, it's a process that can be done and redone until it is right
 
  • Like
Reactions: DavidCP

DavidCP

Member
Dec 28, 2017
34
8
8
28
After pondering it quite a bit, I think I might try my hand at a Friction Drive. It rarely rains here so I don't have to worry too much about that.
That and the police here are very particular about anything that "looks" like a motorcycle despite being legal here. So a Friction Drive might avoid that concern too.

The biggest concern I had was I couldn't make the back sprocket and chain design safe enough that I would trust my life on it. I think the biggest problem is this bike is just too small for a center mounted engine.