CR500
Diesel, Snowmobile, & Chainsaw Technician
If your worried about warranty then another muff is a good idea,they do like a muff modd for sure. As said above with the calibration requirements zero resistance on the crank is what is required.
There is afew different ways to modd theses muffs but this is what i found to work well.
Can still put the screen back in this one
This is the go for a ported one
Notice the heat difference the top saw is ported and muff modd from new,bottom saw stock everything.
I'm telling you Andrew... if you want those to shine like new, you need to put a little of this stuff on there. Just follow the steps, I did it on mine and it took it back to factory shine!!!
Mothers® Mag & Aluminum Polish