When you repack your silencer, do you pack it in loosely or tightly?

I repacked the silencer on my yz250 and the silencer on my brother's kx65 around the middle of november. At the time when dissasembled our silencers, mine had barely ANY packing in it. I'm suprised the guy I bought it from went that long without repacking it. My brother's wasn't terrible, but before repacking I remember his bike sounding "poppy". Well, I packed mine tight and his loose (don't ask me why, I didn't plan it that way). And when we took our first rides with the new packing, his felt like a whole new bike almost.. More horsepower, way better throttle response, smoother powerband, and it sounded amazing. The way I would describe the sound is "compressed". Mine on the other hand felt like it had better throttle response... that's about it. Performance was near the same. Also, it sounded exactly the same.

Is the reason that his made a big difference in sound and performance because I packed it in kind of loosely? Or is it just more sensitive to changes like this than my 250?

Also, I'll add that we both have FMF Powercore 2 silencers.

Edited by Rider of the Plague

right in the midle. i put it in and littly tap the packing down with the butt of a hammder then put some more in, do the same, untill its filled. on my answer CF-2 (iv done it once) i abou 3/4 of a bag of FMF packing in.

I've always wrapped it pretty tight.

right in the midle. i put it in and littly tap the packing down with the butt of a hammder then put some more in, do the same, untill its filled. on my answer CF-2 (iv done it once) i abou 3/4 of a bag of FMF packing in.

I think I used the whole bag for mine and about half for his.

I wrapped mine pretty snug. I used the all of the packing, outside of the excess I cut off to fit the length.

If you pack the silencer too tight, it will act like a straight pipe which will make the bike louder and produce less power.

When I done my FMF 4.1 I tried to get it as tite as I could but by the time you wrap and then tape you loose a little titeness so I guess mine was about in the middle.

However after i started it up when I was done I noticed it sounded quieter than before and had a better tone.

With any fiberglass ins the tighter the less effective it will be. Ideal is getting it in without compressing it any.

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