Exhaust Upgrade Theory - Page 3

Megadan · 05-11-2023, 01:50 PM

Pull the carb and just set it to 1 1/2 turns out on the idle mixture. It may not be "perfect" but it works rather well on most bikes with the stock pilot jet.

chiefmeat68 · 06-03-2023, 11:30 PM

Holy Crap!!!!

I finally bit the bullet and replaced my stock exhaust with the one linked in the original post of this thread. HUGE improvement!! It's like a whole new bike!!

I always felt like I had ok power on the low end but it dropped off significantly after about half throttle. My top speed on a flat with no wind was around 52-55mph. I'm 6'4" and 260ish so I figured that was all I should expect from a stock Chinese 229. With the new exhaust I can easily pull 57-62... in fact going down hill I hit 70!! On the way to work today I held 55 at 3/4 throttle for most of the way... even up the hill that used to always slow me down to 50mph. It's peppier thru all throttle positions but most noticeable at higher rpm's now that it can exhale properly.

Also I should mention that I may get more benefit from this mod than others will. I say this because when I took off the stock exhaust the welds I could see were atrocious. I will try to get pics. I would estimate that the first two welds were blocking at least 1/4 of the pipe with big globs of metal from the welds. Who knows what the rest of the welds looked like that I couldn't see. This had me perhaps even more restricted than most.

Another couple of considerations...

The fitment wasn't as easy as the Amazon reviews say. I had to build a little bracket and attach it to the back hand hold fasteners not the original mount for the stock muffler. On the lower middle mount I cut the rubber bushing to make it fit better... but it's still not really flush. I also had to use washers on the exhaust studs so it wouldn't bottom out the nuts due to the flange being thinner. This video is a good explanation of some of the same obstacles I ran into using this exhaust on the hawk...

This exhaust and the 17/45 sprocket change have been the most significant performance upgrades so far.

Other upgrades I've done so far (in order of most to least improvement noticed)...

1. Japanese Cutch Springs - shift like butter... highly recommend.
2. LED headlight - I can see... and more importantly people see me.
3. Spark plug - I honestly can't really tell a difference.
4. Air box mod - I honestly can't really tell a difference.
5. Spark arrestor removal - just louder but no noticeable difference.

Megadan · 06-04-2023, 01:04 AM

Welcome to the club! The exhaust is the single biggest improvement to these bikes without getting into proper engine work such as porting and cams. I am the same size as you and on my first Hawk, which was just an exhaust and a pod filter, I could hit 68mph consistently on flat ground with 17/45 sprockets.

The rest of your mods are pretty much in line with what I consider worthwhile easy upgrades. Just toss on an oil cooler and that would complete the list before taking it to the next level.

Oh, and I found the same thing with the airbox mod when I did it. Switching to a pod filter did a tiny bit more, but I suspect that had more to do with my original intake tube being warped and a bit kinked. Even when I tried to correct it, it was never perfect.

chiefmeat68 · 06-06-2023, 06:40 PM

Hey Megadan...

I bet your "ported and polished" head and header have nothing on this factory beauty!! The craftsmanship is exquisite!!

I think the lumps and weld splatter are strategically placed to create exhaust vortices for proper exhaust gas mixing and greatest resistance prior to the catalytic converter.

For the right price I may be willing to part with this proprietary design if you are looking for the ultimate upgrade...

Megadan · 06-06-2023, 07:41 PM

Quote:

Originally Posted by chiefmeat68

Hey Megadan...

I bet your "ported and polished" head and header have nothing on this factory beauty!! The craftsmanship is exquisite!!

I think the lumps and weld splatter are strategically placed to create exhaust vortices for proper exhaust gas mixing and greatest resistance prior to the catalytic converter.

For the right price I may be willing to part with this proprietary design if you are looking for the ultimate upgrade...

I honestly think that is the worst weld on a factory exhaust I have seen so far. mine was pretty bad, and I have seen a couple others that were total turds, but wow, that's terrible. Your bike probably feels like a Ferrari now

05-11-2023, 01:50 PM	#31
Megadan Join Date: Apr 2017 Location: Omaha, NE Posts: 8,030	Pull the carb and just set it to 1 1/2 turns out on the idle mixture. It may not be "perfect" but it works rather well on most bikes with the stock pilot jet. __________________ Hawk Information and Resource guide: http://www.chinariders.net/showthread.php?t=20331 2018 Hawk 250 - Full Mod list here. http://www.chinariders.net/showpost....62&postcount=1 2024 Royal Enfield Shotgun 650 https://chinariders.net/showthread.php?t=34124
	3

06-04-2023, 01:04 AM	#33
Megadan Join Date: Apr 2017 Location: Omaha, NE Posts: 8,030	Welcome to the club! The exhaust is the single biggest improvement to these bikes without getting into proper engine work such as porting and cams. I am the same size as you and on my first Hawk, which was just an exhaust and a pod filter, I could hit 68mph consistently on flat ground with 17/45 sprockets. The rest of your mods are pretty much in line with what I consider worthwhile easy upgrades. Just toss on an oil cooler and that would complete the list before taking it to the next level. Oh, and I found the same thing with the airbox mod when I did it. Switching to a pod filter did a tiny bit more, but I suspect that had more to do with my original intake tube being warped and a bit kinked. Even when I tried to correct it, it was never perfect. __________________ Hawk Information and Resource guide: http://www.chinariders.net/showthread.php?t=20331 2018 Hawk 250 - Full Mod list here. http://www.chinariders.net/showpost....62&postcount=1 2024 Royal Enfield Shotgun 650 https://chinariders.net/showthread.php?t=34124
	1

06-06-2023, 06:40 PM	#34
chiefmeat68 Join Date: Mar 2022 Location: Eastern WA Posts: 20	Hey Megadan... I bet your "ported and polished" head and header have nothing on this factory beauty!! The craftsmanship is exquisite!! I think the lumps and weld splatter are strategically placed to create exhaust vortices for proper exhaust gas mixing and greatest resistance prior to the catalytic converter. For the right price I may be willing to part with this proprietary design if you are looking for the ultimate upgrade... Attached Thumbnails
	1

06-03-2023, 11:30 PM	#32
chiefmeat68 Join Date: Mar 2022 Location: Eastern WA Posts: 20	Holy Crap!!!! I finally bit the bullet and replaced my stock exhaust with the one linked in the original post of this thread. HUGE improvement!! It's like a whole new bike!! I always felt like I had ok power on the low end but it dropped off significantly after about half throttle. My top speed on a flat with no wind was around 52-55mph. I'm 6'4" and 260ish so I figured that was all I should expect from a stock Chinese 229. With the new exhaust I can easily pull 57-62... in fact going down hill I hit 70!! On the way to work today I held 55 at 3/4 throttle for most of the way... even up the hill that used to always slow me down to 50mph. It's peppier thru all throttle positions but most noticeable at higher rpm's now that it can exhale properly. Also I should mention that I may get more benefit from this mod than others will. I say this because when I took off the stock exhaust the welds I could see were atrocious. I will try to get pics. I would estimate that the first two welds were blocking at least 1/4 of the pipe with big globs of metal from the welds. Who knows what the rest of the welds looked like that I couldn't see. This had me perhaps even more restricted than most. Another couple of considerations... The fitment wasn't as easy as the Amazon reviews say. I had to build a little bracket and attach it to the back hand hold fasteners not the original mount for the stock muffler. On the lower middle mount I cut the rubber bushing to make it fit better... but it's still not really flush. I also had to use washers on the exhaust studs so it wouldn't bottom out the nuts due to the flange being thinner. This video is a good explanation of some of the same obstacles I ran into using this exhaust on the hawk... This exhaust and the 17/45 sprocket change have been the most significant performance upgrades so far. Other upgrades I've done so far (in order of most to least improvement noticed)... 1. Japanese Cutch Springs - shift like butter... highly recommend. 2. LED headlight - I can see... and more importantly people see me. 3. Spark plug - I honestly can't really tell a difference. 4. Air box mod - I honestly can't really tell a difference. 5. Spark arrestor removal - just louder but no noticeable difference.
	1