Air box mod, hawk 250

SensuBeanCartel · 02-18-2019, 06:52 PM

If you wish to install the ebay muffler on a stock airbox without modifications itll rub together, in order to eliminate this you can remove the airbox, grind it flat on the side pictured, put a piece of kydex (bendable plastic) over said area, epoxy it in or water weld it whatever poison you believe is most oil resistant (I used plastic bonder, which is polyurethane based and isnt the best stability wise with motor oil, however I havent seen any issues) , and sand smooth after all is said and done. The reinforcement spline for the pcv oil area remains in tact, and no more heat issues from the muffler. forgive the crappy heatwrap on the muff, and the black paint is exhaust wrap sealer that is black.

Sorry you cant see everything and i didnt take better pictures, but you can tell from the angle it isnt just the stock box.

hard to see it well but you can get the gist of the angle from the picture and how much more clearance there is, notice my pcv tube has oil in it , so the pcv system still works (i need to hot glue a ring around the plug but i havent gotten to it, its still pretty water tight, maybe not weather tight).

https://photos.app.goo.gl/BfREfJN1CiUnQ7D78

https://photos.app.goo.gl/uswmQDQsiEcPJHXg8

roundhouse · 02-18-2019, 08:02 PM

Looks good. I was lucky, mine never rubbed and is far enough away it never melted either. Go figure.

SensuBeanCartel · 02-18-2019, 08:16 PM

Ty, appreciate the input

Mine rubbed on the engine and the airbox :l almost melted a hole but I had enough heatwrap so that it only warped, so i felt this was necessary, I also used liquid electric tape to seal all the gaps in the airbox, the outlet to the carb as the rubber cement from the factory came undone, and around the plate i put in before the heat tape so it was compltely water tight.

Ill post better pictures in the light, with the black paint its almost impossible to see in the night, and i apologize for not taking pictures during the process. Ill post pictures of the inside of the airbox whenever I get to cleaning my air filter (its reusable).

Thats also with 3 layers of the fiberglass heat wrap tape already on there, so theres beyond a good ammount of clearance, I just kept figuring that excess heat soak was robbing me of juice so to speak, so even with the clearance I still wanted a barrier from the exhaust.

timcosby · 02-18-2019, 10:58 PM

mine didnt touch the airbox but was close. all i did was dimple the pipe to get a 1/4" clearance and its been fine. also if you heat wrap it you still got to have that 1/4" clearance from the wrap.

SensuBeanCartel · 02-20-2019, 01:29 PM

The area where the pcv collects oil can be covered as well, which I did. Seems like it is picking up less oil and flinging it around. No matter what even if your exhaust didn't touch the air box with the ebay muffler (would personally never want to spend over a hundred bucks to just dent it into place, albeit it is easier), the heat is soaking into the air box due to its close proximity, robbing the engine of colder air. Cant deny the positive effects of colder air into an engine, otherwise there wouldn't be such a thing as a cold air intake. Heat rises, and the air box is directly on top of the exhaust, the hottest part of the bike, even radiant heat while going at speed will soak heat into the air box, forget idling.

Pictures of the plate covering the pcv chamber, didn't feel like sanding it smooth as its unnecessary.
https://photos.app.goo.gl/kDN7aj6JzSULCaZ88
https://photos.app.goo.gl/jEdts8oRGoRN6jyh9

Picture of the outside of the air box with several heat wrap layers, and the muffler has heat wrap further decreasing clearance. Even with the decreased clearance from the heat wraps there is beyond a gap, helping to keep the air cool in the air box. The black over the fiberglass wrap is heat wrap sealer, which i need to apply more of, and the black around the gaps in the air box is liquid electric tape, to help seal everything.
https://photos.app.goo.gl/LCok47jRYUZR5Cdr9
https://photos.app.goo.gl/Hx823H7H1QGvd1vd6

timcosby · 02-20-2019, 09:13 PM

that cover causes the air to change directions and helps get the oil on the sides and out of the air. it was designed that way. why china man decided we didnt need the cover anymore is any ones guess. some folks have put a piece of a
ss dish scrubber in there to help even more but i dont think it needs it.

SensuBeanCartel · 02-20-2019, 09:22 PM

yea it looked like it belonged there, there was a screw slot that looked unthreaded and a spot where it looks like a guide for a plate lol. Thank you for the insight, also I would like to add that permatex gasket sealer black would probably be perfect for adhering the kydex plate i mentioned to the air box after sanding, since permatex black is designed for oil applications (so long as you get a good bead and dont get a bunch of strands everywhere).

I would like to add that if you add heat wrap to the exhaust if you do dent it to fit like the everyone said, It should look aesthetically the same as a normal pipe with just maybe a little restriction (way easier). Although if you do the shock mod this doesnt take much time away, kind of like doing a pilot bearing and throw out bearing when doing a clutch kit, when youre in there its not so bad.

I cant use a pod filter, I take this bike in mud, and it sees more water than most other bikes since i live in FL and use it as a daily, so I had to optimize the airbox.

SensuBeanCartel · 02-20-2019, 11:48 PM

starting to see more inconsistencies between these bikes, even from hawk to hawk. very interesting that basically there is no quality control lol.

02-18-2019, 06:52 PM	#1
SensuBeanCartel Join Date: Feb 2019 Posts: 74	Air box mod, hawk 250 If you wish to install the ebay muffler on a stock airbox without modifications itll rub together, in order to eliminate this you can remove the airbox, grind it flat on the side pictured, put a piece of kydex (bendable plastic) over said area, epoxy it in or water weld it whatever poison you believe is most oil resistant (I used plastic bonder, which is polyurethane based and isnt the best stability wise with motor oil, however I havent seen any issues) , and sand smooth after all is said and done. The reinforcement spline for the pcv oil area remains in tact, and no more heat issues from the muffler. forgive the crappy heatwrap on the muff, and the black paint is exhaust wrap sealer that is black. Sorry you cant see everything and i didnt take better pictures, but you can tell from the angle it isnt just the stock box. hard to see it well but you can get the gist of the angle from the picture and how much more clearance there is, notice my pcv tube has oil in it , so the pcv system still works (i need to hot glue a ring around the plug but i havent gotten to it, its still pretty water tight, maybe not weather tight). https://photos.app.goo.gl/BfREfJN1CiUnQ7D78 https://photos.app.goo.gl/uswmQDQsiEcPJHXg8 Last edited by SensuBeanCartel; 02-20-2019 at 02:12 PM.
	0

02-18-2019, 10:58 PM	#4
timcosby Join Date: Nov 2016 Location: robertsdale alabama usa Posts: 1,007	mine didnt touch the airbox but was close. all i did was dimple the pipe to get a 1/4" clearance and its been fine. also if you heat wrap it you still got to have that 1/4" clearance from the wrap. __________________ 1991 harley heritage softail classic 2016 hawk kaw h1 400 tripple 13' long chopper in progress 2009 johnny pag bar hog 2004 hd electra glide ultra classic shriner edition 1997 harley davidson 1200 sportster 1972 harley davidson amf sx250
	1

02-20-2019, 01:29 PM	#5
SensuBeanCartel Join Date: Feb 2019 Posts: 74	The area where the pcv collects oil can be covered as well, which I did. Seems like it is picking up less oil and flinging it around. No matter what even if your exhaust didn't touch the air box with the ebay muffler (would personally never want to spend over a hundred bucks to just dent it into place, albeit it is easier), the heat is soaking into the air box due to its close proximity, robbing the engine of colder air. Cant deny the positive effects of colder air into an engine, otherwise there wouldn't be such a thing as a cold air intake. Heat rises, and the air box is directly on top of the exhaust, the hottest part of the bike, even radiant heat while going at speed will soak heat into the air box, forget idling. Pictures of the plate covering the pcv chamber, didn't feel like sanding it smooth as its unnecessary. https://photos.app.goo.gl/kDN7aj6JzSULCaZ88 https://photos.app.goo.gl/jEdts8oRGoRN6jyh9 Picture of the outside of the air box with several heat wrap layers, and the muffler has heat wrap further decreasing clearance. Even with the decreased clearance from the heat wraps there is beyond a gap, helping to keep the air cool in the air box. The black over the fiberglass wrap is heat wrap sealer, which i need to apply more of, and the black around the gaps in the air box is liquid electric tape, to help seal everything. https://photos.app.goo.gl/LCok47jRYUZR5Cdr9 https://photos.app.goo.gl/Hx823H7H1QGvd1vd6 Last edited by SensuBeanCartel; 02-20-2019 at 02:47 PM.
	0

02-20-2019, 09:13 PM	#6
timcosby Join Date: Nov 2016 Location: robertsdale alabama usa Posts: 1,007	that cover causes the air to change directions and helps get the oil on the sides and out of the air. it was designed that way. why china man decided we didnt need the cover anymore is any ones guess. some folks have put a piece of a ss dish scrubber in there to help even more but i dont think it needs it. __________________ 1991 harley heritage softail classic 2016 hawk kaw h1 400 tripple 13' long chopper in progress 2009 johnny pag bar hog 2004 hd electra glide ultra classic shriner edition 1997 harley davidson 1200 sportster 1972 harley davidson amf sx250
	0

02-18-2019, 08:02 PM	#2
roundhouse Join Date: Sep 2017 Location: N Texas Posts: 706	Looks good. I was lucky, mine never rubbed and is far enough away it never melted either. Go figure.
	1

02-18-2019, 08:16 PM	#3
SensuBeanCartel Join Date: Feb 2019 Posts: 74	Ty, appreciate the input Mine rubbed on the engine and the airbox :l almost melted a hole but I had enough heatwrap so that it only warped, so i felt this was necessary, I also used liquid electric tape to seal all the gaps in the airbox, the outlet to the carb as the rubber cement from the factory came undone, and around the plate i put in before the heat tape so it was compltely water tight. Ill post better pictures in the light, with the black paint its almost impossible to see in the night, and i apologize for not taking pictures during the process. Ill post pictures of the inside of the airbox whenever I get to cleaning my air filter (its reusable). Thats also with 3 layers of the fiberglass heat wrap tape already on there, so theres beyond a good ammount of clearance, I just kept figuring that excess heat soak was robbing me of juice so to speak, so even with the clearance I still wanted a barrier from the exhaust.
	0

02-20-2019, 09:22 PM	#7
SensuBeanCartel Join Date: Feb 2019 Posts: 74	yea it looked like it belonged there, there was a screw slot that looked unthreaded and a spot where it looks like a guide for a plate lol. Thank you for the insight, also I would like to add that permatex gasket sealer black would probably be perfect for adhering the kydex plate i mentioned to the air box after sanding, since permatex black is designed for oil applications (so long as you get a good bead and dont get a bunch of strands everywhere). I would like to add that if you add heat wrap to the exhaust if you do dent it to fit like the everyone said, It should look aesthetically the same as a normal pipe with just maybe a little restriction (way easier). Although if you do the shock mod this doesnt take much time away, kind of like doing a pilot bearing and throw out bearing when doing a clutch kit, when youre in there its not so bad. I cant use a pod filter, I take this bike in mud, and it sees more water than most other bikes since i live in FL and use it as a daily, so I had to optimize the airbox.
	0

02-20-2019, 11:48 PM	#8
SensuBeanCartel Join Date: Feb 2019 Posts: 74	starting to see more inconsistencies between these bikes, even from hawk to hawk. very interesting that basically there is no quality control lol.
	0