![]() |
#16 |
Join Date: Jun 2011
Posts: 1,335
|
The smog system on motorcycles are nothing but air injection systems that injects air into the exhaust stream, just past the exhaust port. It fools the emissions test into thinking the engine is running cleaner than it actually is.
|
![]() |
![]() |
#17 | |
Join Date: Jan 2012
Location: ChCh , NZ
Posts: 2,264
|
Quote:
theres a little bit more to it than that.... the air/O2 lets the cat burn any unburnt fuel that enters the pipe.... ever wondered why a big single pops / bangs & back fire out the pipe while coasting on a trailing/closed throttle.. Red hot cat / unburnt fuel & O2 .. it all adds up to bang... burnt in the pipe not coming out the back.. wait till yer see what coming.... Euro4 for bikes comes in this year in europe.. one of the driving forces behind all these 2 cyclinder ADV bikes.. it's easyer to deal with 2 smaller charges of exhaust gases with the limited space a bike has that one big charge like from a big single... Euro4 is the sole reason Yamaha has stoped production of the 660cc single and is bringing out a 700cc twin cyclinder Tenere... uses the MT07 motor.. ..
__________________
09 XT660R ... 06 TTR250 ... 80 Montesa H6 125 Enduro... 77 Montesa Cota 348 MRR "Malcom Rathnell Replica"... Current resto projects.. 81 Honda CT110... 80 Kawasaki KL250A1... 11 Husaburg TE125 enduro... "sold" along with another 31... Lifan 125 Pitbike.. "stolen" ... KIWI BIKER FORUM...... http://www.kiwibiker.co.nz/forums/content.php All the best offroad rides in NZ... http://www.remotemoto.com/ E-mail... xtpete1@gmail.com |
|
![]() |
![]() |
#18 | |
Join Date: Jun 2011
Posts: 1,335
|
Quote:
![]() |
|
![]() |
![]() |
#19 |
Join Date: Mar 2010
Location: Volcano, Ca
Posts: 7,112
|
That's why it's a good thing to disable the air injection unit if you delete the cat or change your pipe. That shot of O2 that's supposed to get tossed on the cat like a blow dryer on a briquette, now can blast your muffler packing on the way out.
__________________
"Light a fire for a man, and you heat him for a day. Light a man on fire, and you heat him for the rest of his life." 2007 Suzuki DRZ400S (SM convert) 2009 Q Link XP 200 1967 BSA B25 250cc Starfire 2022 Royal Enfield Interceptor 650 2023 Royal Enfield Scram 411 1948 Royal Enfield Model G 350 |
![]() |
![]() |
#20 | |
Join Date: May 2017
Location: South Jersy
Posts: 1
|
Quote:
|
|
![]() |
![]() |
#21 |
Join Date: Jun 2011
Posts: 1,335
|
The air injection system (smog crap) won't cause a stall unless there's a vacuum leak to it. It will cause exhaust popping. It injects fresh air into the exhaust just past the exhaust valve. Always check the valve clearances on these bikes when you get them. They're almost always too tight and can cause running issues. You may need to clean the carb if you've been riding a lot and install a fuel filter. make sure the fuel filter is rated for gravity flow. Also, the idle on these bikes should be between 1200 and 1500 rpm. I know there's not a tachometer on most China bikes, so it has to be done by ear, or add a tach on. Even thought the factory carb and jetting is complete crap, it should still run ok. The bike just won't provide maximum power.
|
![]() |
|
![]() |
![]() |
Tags |
apollo 250, cat removal, emissions control, epa |
|
|