Here's the nosie quotes from the HMF site:


Stock muffler 80db @ idle.
Stock muffler 88db @ 5,250 rpm.

HMF Slip on open 87db@ idle.
HMF slip on open 95db @5,250 rpm.

HMF slip on w/quiet core insert 80db@ idle.
HMF slip on w/ quiet core insert 89db @ 5,250 rpm.

Adding the QCI did not kill power as it is about the same size as the muffler core.
Removing the QCI takes seconds to do, 3 allen screws remove the tip slip the QCI on and reinstall the tip.
See this:
http://hmfengineering.com/forums/showthread.php?t=1415

The best runs are:
#12 BLUE fuel screw 2.0.
#13 RED fuel screw 2.5.

Compare them to run # 16 GREEN with the Quiet Core Insert added, there was no power loss.
Attached Images


As for the muffler interference with the rear fender, Mine was supplied with a longer fastener and spacer.

 

its nice to see the other option for exhausts for the bike, so now we have big gun, muzzy, hmf... is that all?

 

Yes, I've already read the thread with sound figures, thanks though.

What I'm concerned about is not what a db meter in the immediate area of the pipe will tell you. This muffler makes a much lower note than the stock exaust. As we all know, low frequencies carry much further than the higher pitched, stock sound will. Same principle if I read 89 db one foot away from the sound of a violin and take a separate reading of a base drum that is also 89 db at that same one foot distance. Go inside my neighbor's house 30 feet away and the bass drum will a lot louder than the violin. I think I'm getting carried away here, but I'm sure you see the point.
I was wondering if anybody had a stop-gap method to further deaden the noise until I get out of my immediate neighborhood and onto a more main road, other than having to push the bike. [8D][8D]

 

id just ride it... disturbing the peace is only from 10 pm to 7 am... so i just ride...

anyone else think the bike sounds like a quad? i have the big gun and it sounds alot like a quad imo...

 

Hehe, Japan treasures their peace and quiet more than any other country I've been in. Noise will drive otherwise passive people to outright violent acts. I usually start my bike at 6:00AM. It sure makes me wish I had one of those jobs that start at 8:00AM or later. Oh well, where there's a will, there's a stubborn thumper rider who finds a way or gets his bike burned to the ground.

I personally haven't heard quads with after market exhausts, so I can't make a very good comparison. We have some Yamaha Grizzly 660's at work that have a pretty good sound to them....even though they we are running the stock pipe. They definitely sound better than this bike does in stock form.

 

AH HA, i forgot ur in japan... lots of different laws..... by the way you speak/ write english very well.

 

You know I was Freaked out by how loud I thought the bike was too, even with the insert!
So, I had my wife come out and listen as I drove out the drive and down the road about a mile.
Her reply was "what are you so worried about? It's Fine! You can hardly here when you a few lots downs the road!"
You know I didn't believe her so I had a friend ride it a few days later and guess what??? She was right !!! (ya ya )
It's it amazing how the bike sounds while riding it but the insert obviously attinuates ( I know this is spelled wrong ) the sound so at a distance it disapates.
Works for me !!!!!!

 

Ha ha - my wife said the same thing when I asked if the Muzzy with quiet core was too loud and her response was, "no - it sounds great, it actually sounds like a motorcycle now." I was all concerned before I got it, but after a few rides I wondered how I ever got along without it.

 

I start mine at 2.30am some days to go to work, thats why I don't want more noise. I'm guessing my neighbours would wan't a lynching if I did that (I'd be the same if some goose started a noisy bike at 2.30am)

 

Man, don't ya' just hate it when that happens! [sm=bustedsign.gif]