We have a 2009 150R with a HC piston, Cam and a full DRD exhaust.  DRD is at 100dB.  Need to quiet it down to 96dB.  Looking for an exhaust or exhaust mod to do this with minimizing the power loss.  
thanks

You can take it DMC and have him make you a one off pipe.

Try a DB Dawg first. But read through the stickie thread at the top of this forum for more ideas.

Thanks for your reply, however I do not know what a DB Dawg is.  We received a new cone shaped sparky from Dubach Racing and will repacked the silencer they think this may reduce the sound some, but doubt it will give a 4dB reduction.

I did read the sticky, but want to see if anyone has had success with any of the FMF or other non OEM pipes with a modded engine.  My son weight is only 95lbs, bike is regeared correctly for his type of racing, the bike is set up with the proper suspension and valving  front & back, have great motor work (low & mid power biased), FWW, G2 throttle cam so he can adjust the power deliver to the terrain condition, just need to find a way to quiet it down and keep the power up.

The bike is being built for the 2012 Motion Pro Youth Hare scrambles series here in California.  My son wants to race this bike instead of his KX-100 for part of this season. He said that he feels much quicker with the 4-stroke, over the KX, but the times are pretty close, just less shifting and clutching with the 150R. Never worried about noise on the KX.

A DB Dawg is an aluminum insert to lower the decible level. I suggest googling it or check ebay. From what I've read, the OEM pipe is very, very good.

Thanks,
I'll check on ebay for this and an oem exhaust.   Ours is gone.
Nick

I grabbed the stock muffler/spark arrestor from a 250x, for the most part it bolted on. Two of the three mounts are an exact match, the third requires a simple bracket mod. The stock muffler cost me 50$, I made the bracket myself, pretty simple if you have any fab skills whatsoever. It quieted down the bike a ton and you get a spark arrestor outta the deal. You will need to re tweak the fuel air ratio a bit as it has a different backpressure profile for the engine but its way tuneable.

I can shoot you pics if you would like. It fit pretty well with the stock plastics, the muffler from the 250x is longer and maybe a fuzz more girth to it but it fit fine.

Cary

My pro circuit pipe is around 112 decibels wide open...DNR hasn't givin me any problems. We also have the 96 rule,  unless its a big deal, i would just put in the quiet core (if it came with one) or forget it.

caryandreg said:

Cary can you send me a couple of pics?  I'd like to check it out.

0honda said:

Unfortunately in California the 96dB rule is strictly enforced for both MX and Hare Scrambles series.  Honda or an exhaust company needs to ind a solution for this bike!!

Edited by caryandreg, 29 December 2011 - 08:00 AM.
got my pic working

I had to build a bracket to connect the very last mounting point. it was pretty simple, everything else bolted right up. you will need to tweak the jetting as it changes the backpressure prfile in the carb significantly, it will bog off idle really badly if you dont.

plastics didnt fit perfectly, but they did fit well after one small mod.

plus you get the spark arrestor, I picked the SS muffler up off of ebay for 50$

cary

caryandreg said:

Hi Cary,
It does look good.  We will probably try one of these if we cannot get test results from anyone that has tried to quiet this bike down with off the shelf products.
How is the weight and the performance with this.  We have an R&D power bowel with a tuneable leak jet so we can probably dial out the bog.

We are thinking about an FMF Q4 (standard 96dB) or a Ti Power core with a 96dB Insert to see what keeps the sound low and power up.  Hopefully some has already tried this with a slightly modded motor (HC piston and slight porting).  
Nick

Stuck a cheap Lexx sparky on my daughter's 150.  Quieted it right down.  Embarrassingly, even though I have a tester, never checked it after the install, but it was notiably quieter.

District 36 AMA hare scrambles series will send you home for sure if yo are over 96 db.
post up on the D36 message board and you should be able to find someone running a 150r that is passing sound.
We have not had ours checked yet but the Pro Moto Billet end with spark arrester did quite down the stock pipe.

Bethumped, on 01 January 2012 - 12:27 PM, said:

Weight wise it's almost double. Power wise it's a big loss even after the jetting change. Great for a trail bike but for racing there's better options. Power wise nothing beats the stocker

Hi guys,

I have also been looking into this for ages and struggled so far to come up with a solution. Clubs around me in the UK have a strict policy of 94db. I am not a mechanical engineer and am looking for a solution that I could just "plug and play" without many mods. Anyone managed to get theirs down to 94db? I looked on ebay uk for DB Dwag but nothing. Was also looking at FMF powercore with a optional 94db insert but it's a lot of money not being sure it actually works. I tried asking the guys selling it but they couldn't promise it would work for sure.
Any help appreciated as I really wanted to start doing some enduro soon.

Cheers

Plenty of local bikes with the Pro Moto cap and spark arrester passing 96db. you will need to repackage the can every 20 hours or so to keep it quite.