Too Modify or Not Too Modify????

Has anyone finished drilling out the 3/4 depth holes in their Pro-Moto Silent Insert?

I purchased a 98 WR 400 this spring. I've done all of the free mods, and I must say I'm quite impressed!!! The problem is my track, (in my back yard) is in my neighbors front yard. And with it uncorked it's a bit loud when I'm on my Weekend Stress Reduction Program. I bought the Silent Insert, but with the reduction of noise comes the reduction of power, and I like the way it hits when it's breathing freely.

So I'm wondering what would happen if I drilled out the outer holes all the way? And I hate to wreck the insert if it's not going to gain me anything.

Thanks for any input.

i did that to my pmb insert when i first got my 04 wr450, it works well and is a good medium between the two. it helps the top end the most from what i could remember,and makes it sound like a indy car! just make sure to take off the rubber seal before drilling. :)

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