Header Wrap !! thats an good idear !!

i have glassed a tuned pipe tunnel for my sundowner ,just round foam from pipe isolation as a mold, couple of glas and epoxy around
and it was done to keep the heat out of the fuse.

some bears did make 150 + with 180 saitos
you must be faster with the bvm

what is done to the bvm to make it the speed version ? special liner/piston from specialtys ?

the 170 YS supercharged 4 stroke is my favorit for the bear
i the meantime , i fly my robbe little fast foamie rare bear .........