Some help needed.

[Alaskavan]

That bike is sayin' "right hand belt drive" to me. From what I read today, I'd guess the power band is from 3,600 - 5,000. I couldn't find anything on torque.

I PM'd Doug with a request for help.

 

[32motleycrue]

Well the thing is its a 6:1 ratio. I dont know how that will affect it, and how I would go about making this bike roll.

THanks for your help though.

 

[mickey]

Will the shaft be rotating in the correct direction? That gear box looks like it reverses the rotation.

 

[32motleycrue]

As it sits in the frame, the shaft rotates clockwise. THe box does change the direction.

 

[Alaskavan]

5-7 or Dud3x3 will be able to supply better figures, but this may give you something to think about. The Happy Time engines have a built in reduction of (I think) about 4:1. Just get Jpilot's gear ratio calculator, input numbers, and see what it tells you.
Note. The mph part of the equation is subject to external forces.

 

[5-7HEAVEN]

Brother, you've got skills!

Still awaiting engine stats, so we can estimate gears/mph/speeds for you.

What diameter is your reduction gear shaft?

Myron

 

[jpilot]

Great looking project!

I think you can safely assume that the "4 HP/5200" means 4 horsepower at 5200 RPM (engine RPM). With the 6:1 built in speed reducer that means you'll need an additional reduction of 1.28:1 to realize 40 MPH with a 20 inch wheel. That's an overall ratio of 7.68:1.

I see that there is a governor built into the engine. You'll want to get rid of that of course.

The biggest problem you may have is coming up with a clutch if there's not already a centrifugal clutch in the gearbox. Does the output shaft turn when you pull the rope starter slowly? If not then there is a clutch built into the gearbox and that greatly simplifies things. If it does turn then you're going to have to come up with an external clutch of some sort. A centrifugal clutch on the output shaft of the gearbox won't work because of the built in reduction. You wouldn't be able to spin the clutch fast enough to make it engage.

If there is a built in clutch you could simply offset the engine to the left and run one chain between the output shaft and and the wheel sprocket, again with a 1.28:1 (or close to that) reduction ratio.

Hope this helps.

Jim

 

[Dug3x3]

Hi Motelycrue, I should be able to round up some info for you on this engine. I just got a p.m from Alaskavan to check this out. I have to head out right now but will work on this when i get back. Also one of your engine pics shows the nut missing that holds the cyclinder on the base. Be back soon. doug

 

[Dug3x3]

Motely , can you figure out the numbers in your last pic? I know of a EC04 and 08 . But yours looks like 07? The model number is stamped on the housing behind the recoil/flywheel area. Or behind the carb on the recoil side of engine.

 

[Dug3x3]

You can try here for starters with info on your model .
http://www.robinamerica.com/manuals/engMans.lasso