KPX250 Muffler?

deezdubinmt · 11-04-2023, 04:20 PM

Anyone have any luck finding a serviceable option for a aftermarket muffler for a KPX250? I look at the stock muffler and it screams, "I weigh 25lbs for no particular reason". I don't know if that's how much it weighs, but it looks chunky. I'm a fair fabricator and can extend the pipe out where I can use a slip-on. Just seeing of anyone has found a bolt-on option.

deezdubinmt · 11-05-2023, 06:17 PM

Ok, so officially, it weighs 10.5-11 lbs according to my bathroom scale. Still seems like that could be trimmed down. There's no removable baffles in the can, the chrome end is decorative and it's securely welded and sealed behind the trim part. FYI, the header pipe is 1 3/8" OD, the rest of the system is 1 1/2" OD.

**JerryHawk250** · 11-06-2023, 09:20 AM

One reason the muffle is heavy because that's were the catalytic converter is located.

deezdubinmt · 11-06-2023, 10:28 AM

Quote:

Originally Posted by JerryHawk250

One reason the muffle is heavy because that's were the catalytic converter is located.

Not for long...

deezdubinmt · 11-06-2023, 06:43 PM

I wonder if something like this will work. I know I'd need to add the o2 sensor bung, but that should be pretty easy to do.

https://t.ly/cutTC

deezdubinmt · 11-28-2023, 01:15 PM

I'll post a vid with audio when I get it installed.

BriNbigD · 11-28-2023, 01:43 PM

I’ll be watching with interest! Good luck!

deezdubinmt · 12-10-2023, 01:05 AM

Just an update, I won't have this done before Christmas, but instead of trying to find a mid-pipe that would adapt to the KPX, I had my local exhaust guy take about a 2 foot section of 1.5" exhaust pipe (way longer than needed) and spread one end to slip over the stock size pipe (which is 1.5"). I took the Sawzall to the stock pipe just before the OEM muffler/cat. That way I have all the right geometry around stuff and pointing in the right direction out back. Final assembly will be : stock header -> Stock mid-pipe (cut) -> mid-pipe extension (welded) -> muffler adapter (came with muffler, also welded) -> muffler attached via hooks and springs for replaceability.

deezdubinmt · 12-26-2023, 08:20 PM

So that looks right at home there.

deezdubinmt · 12-27-2023, 07:55 PM

OK, so pretty please with the way things turned out.

A few things I've noticed so far. The db killer (endcap) has gotta go. It's making a "pift pift pift" sound which sounds awful, but that's not the muffler or endcap doing that... The exhaust gases are taking a glancing blow at the turn signal as it's exiting the muffler at high speed. (Plus I don't like the look of it). However without that in there, its WAY to loud. More like a megaphone especially when you jump on it riding (like painfully loud). My extension and adapter all welded up nicely, or as nicely as my skills can do. A little grinding and header paint and nobody's the wiser. Everything lined up well and didn't have to do any special mounts or anything to align the muffler to the rest of the exhaust. So far so good, but I'm going to get some internal baffles and replace my gasket between the header and (now) mid-pipe section.

For anybody who's interested and has taken off the muffler/cat on theirs. The crumbly graphite exhaust seal that goes at the junction between the muffler section and the header section is 35mm (ID) X 43mm (OD).

Desuboi941 · 10-22-2024, 10:06 AM

Quote:

Originally Posted by deezdubinmt

OK, so pretty please with the way things turned out.

A few things I've noticed so far. The db killer (endcap) has gotta go. It's making a "pift pift pift" sound which sounds awful, but that's not the muffler or endcap doing that... The exhaust gases are taking a glancing blow at the turn signal as it's exiting the muffler at high speed. (Plus I don't like the look of it). However without that in there, its WAY to loud. More like a megaphone especially when you jump on it riding (like painfully loud). My extension and adapter all welded up nicely, or as nicely as my skills can do. A little grinding and header paint and nobody's the wiser. Everything lined up well and didn't have to do any special mounts or anything to align the muffler to the rest of the exhaust. So far so good, but I'm going to get some internal baffles and replace my gasket between the header and (now) mid-pipe section.

For anybody who's interested and has taken off the muffler/cat on theirs. The crumbly graphite exhaust seal that goes at the junction between the muffler section and the header section is 35mm (ID) X 43mm (OD).

Hey just curious as to how this worked out for you, did it make a difference in power? Was the ecu able to tune itself or is it leaning out? Also if you could post audio that would be great! I’m stuck between this bike and an Orion rxb250l ho which is actually cheaper I’m just having issues with the website and it’s hard to find out if I’d be able to register it in Michigan. This is what makes me lean more towards the kpx. The only thing keeping me away is that exhaust, it’s ugly imo and I alr had a hawk and couldn’t stand how noisy they were. The exhaust helped with that though. I know if I got this bike I would enjoy it I just also know I couldn’t stand to ride a silent bike, it would drive me crazy.

11-04-2023, 04:20 PM	#1
deezdubinmt Join Date: Oct 2023 Posts: 15	KPX250 Muffler? Anyone have any luck finding a serviceable option for a aftermarket muffler for a KPX250? I look at the stock muffler and it screams, "I weigh 25lbs for no particular reason". I don't know if that's how much it weighs, but it looks chunky. I'm a fair fabricator and can extend the pipe out where I can use a slip-on. Just seeing of anyone has found a bolt-on option. __________________ Current 06 Harley 1200 XLC 95 Honda Elite 23 KPX250 Former Early 80s(ish) Can-Am Rotax 250(retired) 94 Honda 750 Magna (custom) (stolen) 81 Yamaha XS650 Special II (retired)
	0

11-05-2023, 06:17 PM	#2
deezdubinmt Join Date: Oct 2023 Posts: 15	Ok, so officially, it weighs 10.5-11 lbs according to my bathroom scale. Still seems like that could be trimmed down. There's no removable baffles in the can, the chrome end is decorative and it's securely welded and sealed behind the trim part. FYI, the header pipe is 1 3/8" OD, the rest of the system is 1 1/2" OD. __________________ Current 06 Harley 1200 XLC 95 Honda Elite 23 KPX250 Former Early 80s(ish) Can-Am Rotax 250(retired) 94 Honda 750 Magna (custom) (stolen) 81 Yamaha XS650 Special II (retired)
	0

11-06-2023, 09:20 AM	#3
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,714	One reason the muffle is heavy because that's were the catalytic converter is located. __________________ 2024 Linhai 300 ATV 4x4 2023 Lifan Lycan 250 Chopper 2023 Venom Evader 2022 Lifan KPX250 2020 Kawasaki Vulcan S (Sold) 2004 Honda ST 1300 2016 Black Hawk 250 (sold) Keihin PE30 carb,125 main,38 slow.Pod filter,ported & decked head 10:1 CR,Direct Ignition Coil,15/40Sprockets,NGK DPR8EIX-9,De-Cat,Dual Oil Cooler,Digital Cluster 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel
	0

11-06-2023, 06:43 PM	#5
deezdubinmt Join Date: Oct 2023 Posts: 15	I wonder if something like this will work. I know I'd need to add the o2 sensor bung, but that should be pretty easy to do. https://t.ly/cutTC __________________ Current 06 Harley 1200 XLC 95 Honda Elite 23 KPX250 Former Early 80s(ish) Can-Am Rotax 250(retired) 94 Honda 750 Magna (custom) (stolen) 81 Yamaha XS650 Special II (retired)
	0

11-28-2023, 01:15 PM	#6
deezdubinmt Join Date: Oct 2023 Posts: 15	Got a new shiny I'll post a vid with audio when I get it installed. Attached Thumbnails __________________ Current 06 Harley 1200 XLC 95 Honda Elite 23 KPX250 Former Early 80s(ish) Can-Am Rotax 250(retired) 94 Honda 750 Magna (custom) (stolen) 81 Yamaha XS650 Special II (retired)
	1

11-28-2023, 01:43 PM	#7
BriNbigD Join Date: Oct 2023 Location: DFW Posts: 64	Following I’ll be watching with interest! Good luck! __________________ DFW HMCM(SW)[Ret] 2020 FLHTK 2023 EX400G Ninja 400 2023 Hawk DLX
	0

12-10-2023, 01:05 AM	#8
deezdubinmt Join Date: Oct 2023 Posts: 15	Just an update, I won't have this done before Christmas, but instead of trying to find a mid-pipe that would adapt to the KPX, I had my local exhaust guy take about a 2 foot section of 1.5" exhaust pipe (way longer than needed) and spread one end to slip over the stock size pipe (which is 1.5"). I took the Sawzall to the stock pipe just before the OEM muffler/cat. That way I have all the right geometry around stuff and pointing in the right direction out back. Final assembly will be : stock header -> Stock mid-pipe (cut) -> mid-pipe extension (welded) -> muffler adapter (came with muffler, also welded) -> muffler attached via hooks and springs for replaceability. __________________ Current 06 Harley 1200 XLC 95 Honda Elite 23 KPX250 Former Early 80s(ish) Can-Am Rotax 250(retired) 94 Honda 750 Magna (custom) (stolen) 81 Yamaha XS650 Special II (retired)
	1

12-26-2023, 08:20 PM	#9
deezdubinmt Join Date: Oct 2023 Posts: 15	Done So that looks right at home there. Attached Thumbnails __________________ Current 06 Harley 1200 XLC 95 Honda Elite 23 KPX250 Former Early 80s(ish) Can-Am Rotax 250(retired) 94 Honda 750 Magna (custom) (stolen) 81 Yamaha XS650 Special II (retired)
	3

12-27-2023, 07:55 PM	#10
deezdubinmt Join Date: Oct 2023 Posts: 15	OK, so pretty please with the way things turned out. A few things I've noticed so far. The db killer (endcap) has gotta go. It's making a "pift pift pift" sound which sounds awful, but that's not the muffler or endcap doing that... The exhaust gases are taking a glancing blow at the turn signal as it's exiting the muffler at high speed. (Plus I don't like the look of it). However without that in there, its WAY to loud. More like a megaphone especially when you jump on it riding (like painfully loud). My extension and adapter all welded up nicely, or as nicely as my skills can do. A little grinding and header paint and nobody's the wiser. Everything lined up well and didn't have to do any special mounts or anything to align the muffler to the rest of the exhaust. So far so good, but I'm going to get some internal baffles and replace my gasket between the header and (now) mid-pipe section. For anybody who's interested and has taken off the muffler/cat on theirs. The crumbly graphite exhaust seal that goes at the junction between the muffler section and the header section is 35mm (ID) X 43mm (OD). __________________ Current 06 Harley 1200 XLC 95 Honda Elite 23 KPX250 Former Early 80s(ish) Can-Am Rotax 250(retired) 94 Honda 750 Magna (custom) (stolen) 81 Yamaha XS650 Special II (retired)
	0