I heard on here somewhere that the plastic is reinforced with fiberglass. With that being said, I wonder if gel coat like what they use on fiberglass bodywork would hold up on a saw.
There are literally tons of threads on this site explaining how to properly tune a carb. Do some digging, you will find all the information you desire.
http://www.asphaltandrubber.com/bikes/ronax-500-launch/ I always though it would be cool to stuff a rotax mxz670 rotory valve engine in a modern buell frame.
Let me rephrase, the rz350 with a 535 cheetah kit will spank a 600 on a road course. The 350 is a lighter, more nimble bike. Two strokes have always had better power to weight ratios.
I really don't have any experience buffing chainsaw plastics. I do however have experience with spray paint and can tell you that it unfortunately will not hold up. Good luck with them!
I would love to get my hands on a yamaha rz350! I have seen plenty of vids where guys have put the 535 cheetah kits on them and they keep up with modern 600s all day.
I use to work in waterproofing and foundation repair. The company I worked for stood by zoeller. They are definitely heavy, especially when dragging one through a crawl space.
Rattle can paint doesn't hold up in harsh conditions such as on a chainsaw. Your best bet would be to try and buff them with a really fine compound or go with new ones.
I would get it either way. I have it's little brother the 550. Its 85cc and a screamin demon. When I can muster up the funds, I will definitely have one.