Posted by Joe S. on January 26, 2001 at 10:14:56:
In Reply to: Re: Re: Re: Re: Re: Re: Why The 621 is so expensive? posted by Chuck Jackson on January 25, 2001 at 09:30:40:
You have to be as careful as the dickens, but coming in from the top or bottom (or both) metal can be drilled out to a certain point in the "V's" of the rotors. (Take a look at how they are shaped - from a side view.)
I have only done this ONCE. It was on any early Mira-181 F (B&S copy). Its rotors were slow as molasses, ' cause they were too massive and too big. I WAS successful in speeding them up some, but there was still this issue of surface area for which there obviously was no remedy.