Grubee engine; made for speed (NOT!)

[James morash]

Here's the 8 reasons the engine is weak;

1. carb has no true idle jet which causes loss of power at all rpm's
2. head compression is too low
3. intake and exhaust ports are too narrow, and intake is too high
4. transfers are too narrow so that attempts at turning the engine into a high rpm screamer fail
5. crankcase compression ratio on the 48cc is only a pitiful 1.1 which provides only 1.5psi when the pistons uncover the transfer ports. Such a low pressure greatly limits power. 3psi is the bare minimum needed.
6. CDI does not retard the ignition timing at high rpm's which limits power and creates too much piston/cylinder heat. It also produces a very weak spark.
7. piston/piston-pin weight is not correct to match the counterbalancing of the flywheels which causes upper rpm engine vibration which limits power.
8. The exhaust is just a straight pipe with muffler. The lack of a true expansion chamber limits both low rpm grunt and high rpm speed.

I got burned on these cheaply made crap the clutch was mess up right from the box supposedly it was a new motor and then I got another one sent to me but that one blew up in 20minutes of riding and no warranty they say misuse of the motor I mounted that even and next morning started to head to work damn thing seized up soild on me skidded my tire to screwed that right up and I was only going around 30-35km Cause I didn't want to be too rough on the new engine