i have the same problem when i run my hvmaxx motor in my crt.5 as well, i think its 2 times louder then my 9l, i just my try this as well, i had a thread awhile back on this but my first attemp didnt work out so i have been putting up with the noise, but my try again
I like the robinson gear, if I had to do this agin I would use that gear as it already has the holes in it. I am going to get everything shimmed up right and give it a try tomorrow. Hope it works!