hey pete.

i have a 58cc and i used a da50 slimline muffler after having to modify it. it took me 20mins with a tig welder and a drill press. i have a good steup now and i cannot complain about noise or power. i could only assume that a slimline da50 muffler would make your 45 work well because of its open and non restrictive nature. i had a lot of problems trying to track down a muffler for my engine and i can only guess you are going through the same deal. that slimline muffler is light weight also.

i hope i have helped


aerowiz.