Cleaning The Cat

itsnt4me · 09-24-2018, 01:31 PM

Seems that some folks say they didn't get much out of cutting the cat material out of their exhaust and that they got more benefit from drilling out holes in the muffler. I wanted to get some of the back pressure out of the engine but didn't way to go to all the trouble of cutting out the cat and rewelding if there wasn't much of a benefit but drilling holes out of the muffler canister would be a lot simpler. I got rid of my welding equipment because I have a pacemaker and can't be around welding so was curious what you guys think. Would like to keep the stock exhaust because I like the way it looks. And I am cheap.

**JerryHawk250** · 09-24-2018, 01:42 PM

Gut the cat and bring it to a local muffler shop to weld it back. Probably get it done for about $20. That alone was a huge increase in performance on my Hawk. I'm still running the stock exhaust.

itsnt4me · 09-24-2018, 02:58 PM

Quote:

Originally Posted by JerryHawk250

Gut the cat and bring it to a local muffler shop to weld it back. Probably get it done for about $20. That alone was a huge increase in performance on my Hawk. I'm still running the stock exhaust.

Did you also drill out the muffler canister?

**JerryHawk250** · 09-24-2018, 03:01 PM

Quote:

Originally Posted by itsnt4me

Did you also drill out the muffler canister?

Yes, That help a little more but not as much as gutting the cat. You will also need to up the main jet to a 110 or 115.

itsnt4me · 09-24-2018, 03:42 PM

Quote:

Originally Posted by JerryHawk250

Yes, That help a little more but not as much as gutting the cat. You will also need to up the main jet to a 110 or 115.

For sure on the rejet. Just put a new NGK plug in a few minutes ago and I am already lean. Again thanks for the info.

itsnt4me · 09-24-2018, 05:46 PM

I am going to want to cut a window out and not cut the entire pipe. If you used the window method what tool did you use to cut it out. Dremel?

**JerryHawk250** · 09-24-2018, 05:48 PM

You could use a cut-off wheel on a small hand grinder.

AresROC · 09-24-2018, 08:04 PM

Hmmm, I like the cat, lol. Don't want to be too smelly like my GSXR, but since this is only a 250 maybe there is not smell?

I would drill out the muffler just for the deeper noise... anyone have resource on how to pull the internals out?

Cravin01 · 09-24-2018, 09:23 PM

might help?

roundhouse · 09-24-2018, 09:53 PM

The hawk does not have the gas smell after removing the cat. At least not like my old R6. I still have the cat in my other bike as I get not wanting to smell like fuel after riding.

**JerryHawk250** · 09-25-2018, 01:01 PM

Unlike the Storm, the Hawk cat is single wall construction so won't be as bad to do as Paul's

Cravin01 · 09-25-2018, 08:48 PM

I didn't know that, I sure would like to see a Hawk up close to see what is shared if anything? I was thinking maybe the tanks could be swapped so I could get a fuel gauge.

timcosby · 09-25-2018, 10:34 PM

Quote:

Originally Posted by AresROC

Hmmm, I like the cat, lol. Don't want to be too smelly like my GSXR, but since this is only a 250 maybe there is not smell?

I would drill out the muffler just for the deeper noise... anyone have resource on how to pull the internals out?

when you open up the cat and see how restrictive it is you will wonder why it even run with it in and i have no smell on the hawk.

timcosby · 09-25-2018, 10:36 PM

Quote:

Originally Posted by itsnt4me

I am going to want to cut a window out and not cut the entire pipe. If you used the window method what tool did you use to cut it out. Dremel?

cut a big window too cause that mother doesnt want to come out of there and welding the shitty metal is a bear. i chased hole with the welder till i got tired and ordered aftermarket.

Biker_Andy · 09-26-2018, 07:58 AM

Is the Cat under the heat shield on the Hawk too?

My TT250 has a long slight bulde under the heat shield and a big stubby bulde where the muffler attaches to the mid pipe. It seem bigger then it needs to be for just a coupling. I assume it's hidden under the heat sheild because it would be way too convenient to remove if it was in the coupling.

09-24-2018, 01:31 PM	#1
itsnt4me Join Date: Aug 2018 Posts: 47	Cleaning The Cat Seems that some folks say they didn't get much out of cutting the cat material out of their exhaust and that they got more benefit from drilling out holes in the muffler. I wanted to get some of the back pressure out of the engine but didn't way to go to all the trouble of cutting out the cat and rewelding if there wasn't much of a benefit but drilling holes out of the muffler canister would be a lot simpler. I got rid of my welding equipment because I have a pacemaker and can't be around welding so was curious what you guys think. Would like to keep the stock exhaust because I like the way it looks. And I am cheap.
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09-24-2018, 01:42 PM	#2
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,846	Gut the cat and bring it to a local muffler shop to weld it back. Probably get it done for about $20. That alone was a huge increase in performance on my Hawk. I'm still running the stock exhaust. __________________ 2025 Lifan KPT 400 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 (Sold) 2016 Black Hawk 250 (sold) 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel
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09-24-2018, 05:46 PM	#6
itsnt4me Join Date: Aug 2018 Posts: 47	One More Thing I am going to want to cut a window out and not cut the entire pipe. If you used the window method what tool did you use to cut it out. Dremel?
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09-24-2018, 05:48 PM	#7
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,846	You could use a cut-off wheel on a small hand grinder. __________________ 2025 Lifan KPT 400 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 (Sold) 2016 Black Hawk 250 (sold) 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel
	1

09-24-2018, 08:04 PM	#8
AresROC Join Date: Mar 2018 Location: Las Vegas, NV Posts: 193	Hmmm, I like the cat, lol. Don't want to be too smelly like my GSXR, but since this is only a 250 maybe there is not smell? I would drill out the muffler just for the deeper noise... anyone have resource on how to pull the internals out? __________________ BaShan BSR 250 DB-41H 2018 Red BS250GY-18D JFG Racing Exhaust . Adjustable Shock 320mm . Brozz Digital Gauge . Renthal Fat Bar . 428 17x46 Sprocket . Fender Eliminator . Wheel Truing . Fuel Tank Repair . Keihin PZ30 Main-115 Pilot-38 Needle-1Washer Fuel Mixture-1/2 BSR Chronicles - "Project leads to more projects!" Yamaha WR250R Suzuki GSX-R 600
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09-24-2018, 09:23 PM	#9
Cravin01 Join Date: Jan 2018 Location: Forney Texas Posts: 498	might help? __________________ Visit me on YouTube at "Project Next"! https://www.youtube.com/channel/UC6KTCi2GVbfRDv-2XCqHhsg?view_as=subscriber 2017 Bashan Storm Keihen PZ30 Pumper Carb,115 main jet,35 pilot jet, gutted factory exhaust, Sambo Digital Speedometer,LED blinkers, H4 headlight,D.I.D X-ring chain 428,17/42 sprockets,UNI cone filter.
	2

09-24-2018, 09:53 PM	#10
roundhouse Join Date: Sep 2017 Location: N Texas Posts: 709	The hawk does not have the gas smell after removing the cat. At least not like my old R6. I still have the cat in my other bike as I get not wanting to smell like fuel after riding.
	1

09-25-2018, 01:01 PM	#11
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,846	Unlike the Storm, the Hawk cat is single wall construction so won't be as bad to do as Paul's __________________ 2025 Lifan KPT 400 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 (Sold) 2016 Black Hawk 250 (sold) 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel Last edited by JerryHawk250; 09-25-2018 at 08:50 PM.
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09-25-2018, 08:48 PM	#12
Cravin01 Join Date: Jan 2018 Location: Forney Texas Posts: 498	I didn't know that, I sure would like to see a Hawk up close to see what is shared if anything? I was thinking maybe the tanks could be swapped so I could get a fuel gauge. __________________ Visit me on YouTube at "Project Next"! https://www.youtube.com/channel/UC6KTCi2GVbfRDv-2XCqHhsg?view_as=subscriber 2017 Bashan Storm Keihen PZ30 Pumper Carb,115 main jet,35 pilot jet, gutted factory exhaust, Sambo Digital Speedometer,LED blinkers, H4 headlight,D.I.D X-ring chain 428,17/42 sprockets,UNI cone filter.
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09-26-2018, 07:58 AM	#15
Biker_Andy Join Date: Oct 2016 Posts: 347	Is the Cat under the heat shield on the Hawk too? My TT250 has a long slight bulde under the heat shield and a big stubby bulde where the muffler attaches to the mid pipe. It seem bigger then it needs to be for just a coupling. I assume it's hidden under the heat sheild because it would be way too convenient to remove if it was in the coupling.
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