I just want to pass along some important information about 4 stroke motors. I am not suggesting making any changes to the Whizzer motor, but just passing along general information.
If a 4 stroke motor has less than 100 pounds of compression, several events can take place, first possible poor gas mileage, secondly possible higher operating tempature, low torque, low power, less power when hot, and possible piston, and or cylinder wear. Motors that haven't completed the break-in process would check closer to 80 pounds, and the camshaft can lower the pressure numbers on lean burn motors.
Here is why, with lower compression the cylinder will run rich, and the gasoline can "wash" the oil from the top half of the piston, causing excessive wear and higher operating tempatures. A motor will low compression will also vibrate more [ever had a car with bad valves that shakes?]. It is a known fact that as a motor looses its compression it can be much harder to start, want to know why? More compression will "squish" the air/fuel mixture and put it under pressure, and it appears compressed fuel ignites much easier. Of course if the compression is raised too much, it can also have a similar effect, so the sweet spot on a small bore 4 cycle "flat head" motor is between 100 and 120 pounds when using regular gas. My personal tests have confirmed that hi test fuel is not needed unless the motor exceeds 150 pounds of compression.
I also noticed a comment about using the pedals on a Whizzer to get started and then release the clutch to use the motor, if any of my Whizzers required me to work that hard I would make a few changes to make the motor do the work, not me. A well tuned, completly stock, Whizzer should easily move without using the pedals on level ground.
Hope this information is helpful.
Whizzer OuterBanks LTD
A North Carolina Corporation
Quenton "Lee" Guenther
If a 4 stroke motor has less than 100 pounds of compression, several events can take place, first possible poor gas mileage, secondly possible higher operating tempature, low torque, low power, less power when hot, and possible piston, and or cylinder wear. Motors that haven't completed the break-in process would check closer to 80 pounds, and the camshaft can lower the pressure numbers on lean burn motors.
Here is why, with lower compression the cylinder will run rich, and the gasoline can "wash" the oil from the top half of the piston, causing excessive wear and higher operating tempatures. A motor will low compression will also vibrate more [ever had a car with bad valves that shakes?]. It is a known fact that as a motor looses its compression it can be much harder to start, want to know why? More compression will "squish" the air/fuel mixture and put it under pressure, and it appears compressed fuel ignites much easier. Of course if the compression is raised too much, it can also have a similar effect, so the sweet spot on a small bore 4 cycle "flat head" motor is between 100 and 120 pounds when using regular gas. My personal tests have confirmed that hi test fuel is not needed unless the motor exceeds 150 pounds of compression.
I also noticed a comment about using the pedals on a Whizzer to get started and then release the clutch to use the motor, if any of my Whizzers required me to work that hard I would make a few changes to make the motor do the work, not me. A well tuned, completly stock, Whizzer should easily move without using the pedals on level ground.
Hope this information is helpful.
Whizzer OuterBanks LTD
A North Carolina Corporation
Quenton "Lee" Guenther
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