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R18 TC with drilled out exhaust baffles video

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Thanks for the video !
I can hear pretty clearly it’s not to loud at steady throttle but adds a bit of a deep growl when rev’d - sounds ideal for me as I like the look of the standard mufflers with the Roland Sands end caps, just after a deeper sound without tuning issues.
Do you think this baffle mod needs the Brentune to run properly or will run fine without it (obviously it’ll run better overall with Brentune - just trying to work out if it mess up the standard tune - am hoping the wide band O2 sensors can cope).
👍
 
No this mod doesn't need the Bren tune to run properly. There's nothing new about doing this...Harley guys have done this forever in combination with a high flow air filter (I put in the DNA filter) to make everything breathe better. After a few minutes riding, the computer makes the needed adjustments.
 
Good to hear, I've got the gear - might give it a go tomorrow.
If it's like a few of the videos I've looked at on youtube, it should be a basic holesaw cut through - I suppose the important thing is removing the swarf / metal shards after the work - hopefully a magnet extension rod will get it.
Am not keen on having to remove the mufflers for the job - did you do the holesaw work with the mufflers in-place ?
Thanks for the advice ! (y)
 
Am not keen on having to remove the mufflers for the job - did you do the holesaw work with the mufflers in-place ?
Thanks for the advice ! (y)

I left the mufflers on and just removed the end caps. I used a steel tent peg and hammer to center punch / dimple it to keep the drill bit in the hole saw from walking.
 
Well, did the job yesterday, mufflers left in-place - hardest part was removing the sawed out 'bung' (is very thin ~ 0.75mm thick) as once the holesaw cut through, it bent over and was still hanging on by small section (this happened to both mufflers) and as it wasn't magnetic (assume is stainless steel) I couldn't pull it through with a magnet.
A bit of appropriately bent coat hanger wire did the trick and some 'blue-tack' on the end of a rod to remove the swarf.
Then some black exhaust spray paint to tidy up the internals and, as you said previously, it's pretty hard to tell its not factory when looking inside with a torch.

As for the sound - much the same at idle or constant throttle, but a rev blip or during acceleration there is a slightly louder and deeper growl, which to my ears is a really nice improvement.
On first start up I could tell the bike computer doing some adjustments (initially a rougher than normal startup idle), then it settled down.
Interestingly when riding after doing a couple of rev outs into the range of 4 - 4500 rpm through 1st, 2nd, 3rd gears, it settled down into a slightly smoother / freer breathing rev feel (feels like it rev's a bit quicker and smoother through the 3 - 4000 rpm range).
As I have the DNA filter fitted also (Stage 1 - the frame stage I'll do after I get the Brentune), I suppose with the wide band O2 sensors doing their job, a free'r revving feeling should occur.
Worth doing in my opinion.
 

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This morning I took my bike in for service and got to do a side by side comparison of this muffler mod next to the Freedom Performance mufflers for the same bike - one of the guys at the dealer has them on his bike. The FP exhaust has a deeper, throatier sound with a little more volume while on the throttle. At idle and cruise RPM, the volume is definitely a bit more. The drilled out stock exhaust has a more "raw" sound. A comparison might be a good polished concert violinist compared to someone who just plays the fiddle. Don't take this to mean that the drilled out stock exhaust sounds bad - I think it sounds pretty good; it's just not as refined. The guys at the shop were pretty impressed with how my version sounds, though. The first reaction was "Wow! What did you do to that!?" The sales guy inside even came out when I fired it up to see what was going on :)
 
Yep I’m pretty happy with the drilled out mod too. Thanks for the tip !
JD
 
I followed member Moleculo's advice with a 1-1/4 in holesaw (see pic, with a pilot centre bit fitted to it), you'll also need an extender rod as the baffle plug is about 6in inside or as I did rigged up enough adapters for the reach. Rattles a bit until it centres then a bit of smooth pressure & 30 sec - 1 min and your through.
If you're going ahead, be prepared for a bit of fiddling to retrieve the drilled out plug & swarf !
Good luck !Baffle Holesaw setup pic.jpg
 
As the holesaw begins to finish the cut, you can feel the pressure starting to relieve...kind've like it's becoming butter. When that happens, take pressure off of the drill and ease it through. If the center drill is sharp, and if you get lucky, the plug you drill out will be attached to the center drill bit when you pull it out.
 
As the holesaw begins to finish the cut, you can feel the pressure starting to relieve...kind've like it's becoming butter. When that happens, take pressure off of the drill and ease it through. If the center drill is sharp, and if you get lucky, the plug you drill out will be attached to the center drill bit when you pull it out.
The hole will be larger than the plug after drilling.By starting the bike you should be able to blow the plug out by reving the throttle .
 
The hole will be larger than the plug after drilling.By starting the bike you should be able to blow the plug out by reving the throttle .

Maybe if everything lines up just right but the odds aren't great. But for sure that will happen with all the metal particles - I certainly wouldn't worry about those.
 
Maybe if everything lines up just right but the odds aren't great. But for sure that will happen with all the metal particles - I certainly wouldn't worry about those.
Watch a guy on Youtube and when he started the bike that had a similar freeze plug it blew out on start up,lol.
 
I followed member Moleculo's advice with a 1-1/4 in holesaw (see pic, with a pilot centre bit fitted to it), you'll also need an extender rod as the baffle plug is about 6in inside or as I did rigged up enough adapters for the reach. Rattles a bit until it centres then a bit of smooth pressure & 30 sec - 1 min and your through.
If you're going ahead, be prepared for a bit of fiddling to retrieve the drilled out plug & swarf !
Good luck !View attachment 6093
Could you have gone bigger with the drill bit? Say 1.5"?
 
1.5" is a possibility but it will be very tight.
 
excellent thread for DIY exhaust modding, thanks for posting this.
 
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