| Author | Message | ||
     Johnnylunchbox |
So the Kerker has been way too loud for a long time. I tried repacking and that helped by maybe reducing the sound about 10%. So I decided to take matters into my own hands. I reduced the diameter of the exhaust opening by putting a small metal (don't laugh please) mini mason jar cap. It fit perfectly in the muffler core. The opening is probably about 30% smaller than stock. Then I drilled about 6 rows of 5 1/4" holes on the underside of the can. The idea is to divert/diffuse some of the exhaust gasses though those holes. The result is that back pressure is significantly increased, so I gained some low end grunt, but definitely lost a bit of top end. I will try to reduce the backpressure (too much backpressure can affect the exhaust gas scavenging at the header and cause heat buildup problems right?) by using some stainless steel wool as packing in the area of the holes, and possibly drill some more holes. However, the biggest difference is the sound. I'd say I reduced it to a much more tolerable level. The experiment is not over... | ||
| Ezblast |
Johnny - sounds great! I will be moving this topic to the exhaust section in a day or three. GT - JBOTDS! EZ  | ||
| Johnnylunchbox |
I will try to get some pics up here soon. | ||
| Prichmon |
I installed a spark arrestor and installed the kerker muffler on the centerline pipe. I believe it is a 3s-1750 6with 12 discs. I installed it in the end to create a cap with rivets. I am considering purchasing a resonator to reduce the overall noise. What jetting are you running? I tried doing a 48/180 as suggested elsewhere and I was so rich the bike barely ran. I am currently running 45/170 and may try 175 for the main. 1/8" vacuum slide hole. Rich | ||
| Ezblast |
Try 46 or 48 for the primary and 175 for the main. A stock Kerker would be 45/170. EZ | ||
| Gearheaderiko |
Doesnt sound like a stock Kerker?! Carb tuning is not always one size fits all. If 48/180 seems too rich, it probably is! |
