Brozz 250: Mod - Ebay Exhaust DIY Baffle

[tknj99]

Hi All,

After a recent thread about options to quiet down the Ebay Exhaust, in my case the Stonemen CRF 150/230Exhaust, i decided to try it out and add steps and pics to accomplishing this mod for free.

Difficulty: 2/5
Time: < 1 hour
Improvement: Quiets down the raspiness of the exhaust.. id say it sounds about 20% quieter/muffled at idle and up to wide open.
I still have to test it on the road to confirm as well. A nice benefit of this mod is that it is easily reversible to remove the insert if you don't like it.
Note: i had originally drilled holes into the endcap of my stock exhaust so if your's is completely stock it may wind up being even quieter.

Steps:
1. Using an angle grinder cut-off disc, carefully cut the flattened end off of the stock exhaust
2. Switch out the cutting disc to a grinding disc and carefully grind around the edges to make the end cap as flat as possible. It will later rest against the back edge of the exhaust
3. Switch out the grinding disc to a cutting disc and cut the tube down to size. I cut it where it bends down.
4. Optional: i cut a piece of wire mesh down to size in order to have a make-shift spark arrestor. This gets inserted on the end of the Stonemen exhaust insert. You will have to cut holes for the screws to pass thru and also for the stock baffle piece edge to fit thru
5. Insert the new baffle piece into the end of the Stonemen exhaust
6. Place the Stonemen exhaust metal end cap back against the exhaust end resting over the new baffle
7. Screw the plastic end cap back on

[tknj99]

Update: Baffle 2.0

While its still ice and freezing out i decided to tinker some more with the baffle to make it more in-line with real baffles with acoustic hole passages etc.

Since i previously had cut the pipe down to size i had to figure a way to extend it again and cut grooves in the cut piece end in order to pry it open so that it would fit over the baffle i built already. Once i did this i simply drilled holes and used screws to attach it to the existing baffle.
Next, i drilled acoustic passage holes across both pieces - 14 holes in total. This is a guess as to how many holes is optimal, looking at production baffles online i see many more holes, so maybe ill drill more later, not sure.. any suggestions, im all ears

I tested it out in my shed and its now closer to 30-40% quieter at idle and upwards. I hope to go for a ride tomorrow and will have a better idea of the baffle performance but overall, a nice, easy mod to take the edge off the aftermarket exhaust.. i was happy with the original sound but did notice it was a bit obtrusive on long rides and i'd tend to go wide open and then back off the throttle to stay at a reasonable cruising volume, this will be the test when i get it on the road, seeing how much its helped on an extended ride where full throttle and higher speeds, and by association, volume, are needed while cruising.

[tknj99]

Circling back to this thread for an update:
The baffle did quiet things down across the rev-range at least 30% but i have recently removed the custom baffle as i started hearing lean pops on occasion up top, i also noticed my exhaust mid-pipe section bluing more than it was previously and noticed the end-cap screws starting to get loose.. im thinking the extra restriction was causing it to get too hot and perhaps too much back-pressure im speculating.
I know another member had also custom-fabbed a baffle from the stock exhaust and they later removed it as well, perhaps for similar reasons