Re: Bushings VS bearings
I've been racing with high end 50cc 2 strokes (BZM, Polini, Blata and C1) engines for many years and my opinion is needle bearings. My first HT motor lasted well under 500 miles. When I took it apart it had a bushing in it. The bushing was oblonged and worn almost to the rod. I know it wasn't the oil and ratio because I use Golden Spectrum and run it 28:1. Well to shorten up my story, I ended up reaming the rod and installing a wrist pin bearing off of an Italian Blue Bird motor. After that the motor was faster and lasted until I sold it a year ago. The guy I sold it to commutes to work on it everyday and he told me its still running strong.
The wrist pin does take a lot of beating thats why I decided to install a good quality bearing.