Thoughts on Cat being restrictive......
Cruiser
Joined: May 2009
Posts: 216
Likes: 1
From: Ohio
You only see part of the cat in that pic, its cross section is larger in diameter than the primary, with enough "open"area in the catalyst "mesh" cross section to accomodate the area of the primary. The one true test that nobody has brought to the table is flowbench results, before and after. You make an excellent point about the amount of air that the engine flows compared to the cat, even if there is a slight restriction, it won't effect performance if it still accomodates the engines flow requirements. I had the FM 2:1 pipe and returned to the OEM 2:1 pipe, both tuned properly, you can't tell the difference on the *** dyno.
Some people just aren't gunna get past the visual on how that cat looks in the pipe but Imma with ya Bro!
Road Warrior
Joined: Oct 2007
Posts: 1,468
Likes: 4
From: South Carolina
fabrik8r jump in if you want and help me understand the catalyst.
On a typical new touring bike with no SERT or downloads in its normal state the Catalyst is sitting pretty much fat and happy. If you make adjustments to richen your mixture and exhaust it will cause the catalyst to heat up more to burn away all the (bad stuff)?
So contrary to what most people are saying, yes its true the engine will run cooler with a richer mixture but it will create more heat in the catalyst and start cooking that right ankle.
also, wont a high zinc motor oil clogged that puppy up?
looking to be enlightened.
On a typical new touring bike with no SERT or downloads in its normal state the Catalyst is sitting pretty much fat and happy. If you make adjustments to richen your mixture and exhaust it will cause the catalyst to heat up more to burn away all the (bad stuff)?
So contrary to what most people are saying, yes its true the engine will run cooler with a richer mixture but it will create more heat in the catalyst and start cooking that right ankle.
also, wont a high zinc motor oil clogged that puppy up?
looking to be enlightened.
Outstanding HDF Member
Joined: Jan 2010
Posts: 2,916
Likes: 31
From: earth
fabrik8r jump in if you want and help me understand the catalyst.
On a typical new touring bike with no SERT or downloads in its normal state the Catalyst is sitting pretty much fat and happy. If you make adjustments to richen your mixture and exhaust it will cause the catalyst to heat up more to burn away all the (bad stuff)?
So contrary to what most people are saying, yes its true the engine will run cooler with a richer mixture but it will create more heat in the catalyst and start cooking that right ankle.
also, wont a high zinc motor oil clogged that puppy up?
looking to be enlightened.
On a typical new touring bike with no SERT or downloads in its normal state the Catalyst is sitting pretty much fat and happy. If you make adjustments to richen your mixture and exhaust it will cause the catalyst to heat up more to burn away all the (bad stuff)?
So contrary to what most people are saying, yes its true the engine will run cooler with a richer mixture but it will create more heat in the catalyst and start cooking that right ankle.
also, wont a high zinc motor oil clogged that puppy up?
looking to be enlightened.
Seasoned HDF Member
Joined: Sep 2008
Posts: 20,880
Likes: 33,837
So tell me what is " XIEDs".
Road Warrior
Joined: Oct 2007
Posts: 1,468
Likes: 4
From: South Carolina
The catalyst performs a thermo-chemical process that converts harmfull emisions into inert emissions, the catalyst material requires the heat of the exhaust gas to do it job. Moderate enrichment down to mid/low 13s won't cool the motor, it cools the exhaust gas, and adds residual unburnt fuel. Neither of those conditions are good for the catalyst, but I don't know the long term effects or the details. I don't think modern bikes are passing enough oil to the exhaust to be a problem for the cat, if so, something probably needs repaired or corrected.
the internet is full of ideas and opinions but like you have stressed time and time again, little quantified results.
Thanks for the answers.
OK, got a appointment with dealer to put on header without CAT. (I have Stage I and Rush slip-ons) Shop forman Tried to sell me a Screaming Eagle tuner but I am happy with the way my bike runs now. So then he tells me they may not have to reflash the ECM but if they do it will be $150.
So tell me what is " XIEDs".
So tell me what is " XIEDs".
A stage 1 flash of the ECM will most likely not be enough when upgrading headpipes. Since 2008 all it really does is increase the fuel at wide open throttle by 3-5% and will never richen it beyond 14.7. On most models it will slightly advance the timing and raise the rev limiter by 500.
Ryan
fabrik8r jump in if you want and help me understand the catalyst.
On a typical new touring bike with no SERT or downloads in its normal state the Catalyst is sitting pretty much fat and happy. If you make adjustments to richen your mixture and exhaust it will cause the catalyst to heat up more to burn away all the (bad stuff)?
So contrary to what most people are saying, yes its true the engine will run cooler with a richer mixture but it will create more heat in the catalyst and start cooking that right ankle.
also, wont a high zinc motor oil clogged that puppy up?
looking to be enlightened.
On a typical new touring bike with no SERT or downloads in its normal state the Catalyst is sitting pretty much fat and happy. If you make adjustments to richen your mixture and exhaust it will cause the catalyst to heat up more to burn away all the (bad stuff)?
So contrary to what most people are saying, yes its true the engine will run cooler with a richer mixture but it will create more heat in the catalyst and start cooking that right ankle.
also, wont a high zinc motor oil clogged that puppy up?
looking to be enlightened.
Ryan
Seasoned HDF Member
Joined: Jun 2005
Posts: 12,946
Likes: 32
From: Colorado Springs, CO
No way around it....cats suck, and HAVE to go.
They create a TON of heat, which is passed back into the engine causing the engine temp to rise. As engine temps rise, the ignition is retarded to compensate and stave off detonation. When you retard the spark, you lose power.
But hey, if you like it, go for it.
~Joe
They create a TON of heat, which is passed back into the engine causing the engine temp to rise. As engine temps rise, the ignition is retarded to compensate and stave off detonation. When you retard the spark, you lose power.
But hey, if you like it, go for it.
~Joe
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Outstanding HDF Member
Joined: Jan 2010
Posts: 2,916
Likes: 31
From: earth
No way around it....cats suck, and HAVE to go.
They create a TON of heat, which is passed back into the engine causing the engine temp to rise. As engine temps rise, the ignition is retarded to compensate and stave off detonation. When you retard the spark, you lose power.
But hey, if you like it, go for it.
~Joe
They create a TON of heat, which is passed back into the engine causing the engine temp to rise. As engine temps rise, the ignition is retarded to compensate and stave off detonation. When you retard the spark, you lose power.
But hey, if you like it, go for it.
~Joe
Road Warrior
Joined: Oct 2007
Posts: 1,468
Likes: 4
From: South Carolina
I guess on the oil question was that you could mistakenly put in a GL2 thru GL5 in the crankcase and it has anti scuff additives that are for a gear box (transmission) and not an engine and it will accumulate on the catalyst and eventually clog it up or destroy it. (stressing motor oil is for motors, gear oil is for transmissions)