How can I tell what displacement my scooter motor has??

[rudyauction509]

I recently got a stand up scooter from a friend. I've changed the gearing and am adding disk brakes. One thing I'm not sure of is the size of the motor. There are ~33cc and ~49cc versions, I've had lots of both in the distant past (this is my first one in 4 years). The motor seems to pull hard like a 49cc, yet I struggle on a couple hills that I think a 49cc should get up easier. It has a high flow exhaust that may make a 33cc seem similar to a 49cc. The motor is not marked - I completely removed it and checked everywhere. I need some way of easily determining its displacement as if it's 33cc I'm going to upgrade it to 49cc soon. If anyone has measurements I can do without disassembling the motor I'd really appreciate it. Maybe the width of the outside of the cylinder or something? Or different carb part #'s?

 

[mckutzy]

Post some pics, that will help..

 

[Russ2251]

Measure bore and stroke and do the math.

 

[itsid]

on most engines I've seen the displacement is written (stamped) to the engine itself.
So, upon closer inspection you'll surely find the Info you need

either directly cast into the engineblock, or on a riveted plate or something.

Post pictures of the engine in question, from all possible angles, and I'm sure we can find the label from here

'sid

 

[rudyauction509]

on most engines I've seen the displacement is written (stamped) to the engine itself.
So, upon closer inspection you'll surely find the Info you need

either directly cast into the engineblock, or on a riveted plate or something.

Post pictures of the engine in question, from all possible angles, and I'm sure we can find the label from here

'sid

Getting my camera back tomorrow, I'll get some pictures then.

 

[rudyauction509]

I'm almost certain it's the 33cc, I went accross town to a hill I used to ride on my 49cc scooters without trouble, and I barely made it 20 feet. I'm looking now for a 49cc motor to swap in, and if it is already 49cc I have another frame in need of a motor.

 

[davidbooth1991]

I'm almost certain it's the 33cc, I went accross town to a hill I used to ride on my 49cc scooters without trouble, and I barely made it 20 feet. I'm looking now for a 49cc motor to swap in, and if it is already 49cc I have another frame in need of a motor.

Is it a centrifugal clutch // maybe its a 33 with lower gearing or a 49 that's on it's way out...

 

[rudyauction509]

Is it a centrifugal clutch // maybe its a 33 with lower gearing or a 49 that's on it's way out...

Yes its centrifugal, and it has great compression. I moved it to another frame yesterday and looked in the exhaust port in the process and the cylinder doesn't have a single scratch from what I can see. Also for some reason I gained a bit of power on the new frame even though the motor, transmission, sprockets, wheel are all the same, taken from the old frame.

 

[ML-TOYS]

Pic of the motor from both sides may help