I've probably had my Q4 on for over a year and 3,500 miles. I've never repacked it and I'm trying to decide if I need to do it now. Maybe it's because I haven't ridden my bike for the last 4-days, but it sounded louder today, which made me think about repacking. I know FMF suggests repacking after 20-hours, but who listens to the manufacturers recommendation anyway. But even stretching it, I'm still at probably 60+ hours. What are your thoughts on when to do it?

 

Wow, every 20 hours? I'd be repacking every month!
I have never repacked a muffler, even after accumulating over 80,000km (50,000 mi) on one fitted to a booming v-twin.

I have never run an FMF, but the TBR mounted to my KLX had 15,000km (~10,000mi) on it and always checked out fine with a flashlight & dentist mirror.

Two strokes are another story but I can't imagine any pipe on a 4-stoke requiring that much service...

 

When you get pulled over

 

instead of repacking, just add more packing...it will quiet down dramatically....

 

I have a big box of packing sitting in my garage waiting for me to install it. I only have around 2500 miles on my muffler, bit it seems to be louder than when I got it.

If I could get my darn yard planted... I'd have some time to repack it, in the time it takes me to watch my grass grow...

 

I did my re-pack at 6000m [10,000km]. It only made a very small difference in being quieter after doing!

Don't be scared to use the best bits of the old re-packing to add the not so generous fmf package supplied to re-pack one exhaust!! Use plenty of sealant on the join & leave over night to dry or you will get annoying whisper leaks. Didn't wait long enough on my first attempt.

 

Do you have to remove the slip-on in order to repack?

 

I had 10,000 miles on my Muzzy and when I went to order the packing kit, the guy on the phone said I wouldn't need it. He was right. Still looked new.

 

I haven't packed mine either, deej...but not because I cared.

 

I repacked my fmf q4 once. Once i got it opened up , i realized that it didn't need it. Haven't even considered doing it again since. many many hours on it.
If you think it's loud then maybe repack, but otherwise I wouldnt mess with it.