Small Engines (Lawn Mowers, etc.): brush cutter, oil manufacturers, brush cutter

Question
greetings. i have a kawazaki brush cutter 40cc two stroke, about a week old. I have two questions:
1. even though i correctly mix the recommended 1:25 oil/gas, why is there still white smoke when i increase rpm? does this happen to all two strokes?
2. the engine is really noisy! can i add a silencer at the end of the existing muffler and tail pipe? any tips on doing so? Thanks in advance

Answer
Although the manufacturer recommends a 25:1 mix, this way too rich if you are using a good oil.  They assume the worst and, yes, it will smoke at this ratio.  I recommend following the oil manufacturers recommendation.  As for the noise problem, this is common for a small piece of equipment.  In order to package the unit in as small of space as possible, there is little room to accomodate a decent silencer for the exhaust.  You could search the net for suggestions but I think you may just end up using ear protection as the fix.  Hope this helps.