Catalytic Converter

[Yamacat1000]

I removed my catalytic converter and it has been one of the best things I could have done. It is a pain to remove but it is worth all the profanity uttered. The removal of the cat along with an free flowing exhaust can allows the bike to breath and signifcantly improves performance, engine temps and sound. I have over 1000 miles on mine without it I have had no issues.

Hey fellas, Im new to the site. I work at a Yamaha dealership and my cost on the exhaust is $550 so before I take my two favorite tools (BFH and a pry bar) to my cat I wana make sure it is worth it. Pros vs Cons sorta thing. Any mileage increase or decrease? Do you have any other mods that might contribute to the benefit of no cat? Ive got smog caps and the next day or two a sprocket. Not too worried about runnin lean without the cat.

 

[JRider]

Seeing gas prices and knowing results on OBD1 cars I gutted my converter last week. Low end torque is much stonger and so is the sound there. Still running the factory muffler,maybe why mid-top didn't seem to change. As far as temps and mileage too many variables this soon. Obviously NOT trying to run lean by the smell (all stock). Definitely better ways to find performance but not any cheaper.

 

[Yamacat1000]

Well I gutted mine today, I felt more increase with smog caps in the bottom than eliminating my cat. Noticed a small change in sound with stock muffler, its a lil bit deeper/throaty now. Smells a lot better too, as said before, deff not runnin lean.

 

[lyric911]

Are you all leaving the headers on the bike when you gut the cat? Or removing?

 

[Deleted member 438]

I did mine with the header on, but it's probably easier to do with the header off. You can always come by and trade headers with me.

 

[lyric911]

I did mine with the header on, but it's probably easier to do with the header off. You can always come by and trade headers with me.

Thanks for the offer, but a 4 hour ride one way seems like a bit more of a chore than a couple hours of work.

 

[TeleRob]

Obviously NOT trying to run lean by the smell (all stock). Definitely better ways to find performance but not any cheaper.

Well, by increasing the air flow, you are probably running lean. I'm not sure by your comment if by the smell you think you are running rich. The smell is just all the unprocessed unburnt hydrocarbons now

 

[FZER]

I know one thing when I first crank my bike I'm pretty sure it's running really rich till it gets up to about 120 degrees or so. Correct me if I'm wrong....

 

[TeleRob]

Yeah on first startup it will be rich due to choking. I was talking about normal operation... Increased airflow with no fuel mods would be leaner unless the factory fuel injection is taking care of it. I'm more familiar with carbs

 

[FZER]

Thanks, I guess that explains why it runs like crap too.

 

[Hoover]

I did mine with the header on, but it's probably easier to do with the header off. You can always come by and trade headers with me.

I'll be in the Windy next weekend, would you consider "renting" me yours to see what the difference is?
I'll be in my cage as I am delivering a dog to Lincoln Park.

 

[Yamacat1000]

Are you all leaving the headers on the bike when you gut the cat? Or removing?

I removed mine. I found it very useful when I got the pry bar stuck in there. I took and put the handle in a bench vice, and proceeded to twist the header pipe in circles, seemed to work much better than just chipping away little by little.

 

[Deleted member 438]

I'll be in the Windy next weekend, would you consider "renting" me yours to see what the difference is?
I'll be in my cage as I am delivering a dog to Lincoln Park.

Feel free to come on by and grab it.

 

[FZER]

Mine beat me into submission last night. I got about 3/4 of the way done and I had to give up. My back was killing me and I was running out of day light. I'm going to finish up tonight.

Two things I found that help a bunch. I put my bike up on the trailer just to get it off the ground some. It would be awesome to have a lift to do this.

I also took the vacumm cleaner out with me to get little bits and pieces out. If you don't get them out when you knock them loose you end up just grinding them back into the metal that's left.

Plus, I think it's a good idea to disconnect the O2 sensor, so you don't get crap in it.

 

[chopstic]

So whats the verdict here? Are you guys happy with your cats gutted? I'm thinking about doing it myself as I have gutted the cats on most of the cars I owned and have only good things to say about that. But I don't wanna gut the FZ8 cat unless I know the stock fuel injectors and fuel map can handle it.

 

[JRider]

Surges a bit now if below 3000rpm, seems to be from the torque increase there. Overall after around 7000 miles with nothing else but airbox mod it was worth the effort. ECM tuning not perfect but it can easily wait for new muffler and gearing.

 

[Fazed]

I nearly decided to remove the cat this weekend, but the authorities are starting to clamp down on this sort of thing and it would be a pain in the ass if I have to try and reinstall a cat to pass an emission test if I was caught with out one. I figured that the only way would be to buy another complete header off Yamaha.

So with that in mind, I started looking at aftermarket headers and have decided on the Arrow, due to it's price, looks and low shipping cost. This way, if I get busted for having no cat, I put on original headers and pass the inspection and get back on the road.

My question is, would the power gain really justify the cost?

 

[Alexlycaon]

i wanna try this!

i installed a yoshimura r77 on my fz8, and when i let off the gas it makes a popping sound. What does it mean ? is it running lean? or when i gut the cat this will stop.If you wanna pass the emission test why go through all that trouble just pay the guy extra 10 or 20 bucks. I used to have a 96 ford taurus, check engine light bad tires, it was a piece of crap, but i pay a couple extra dollars and done pass the inspection. I am sure theres gotta be people that will do the same for bikes. thank god i live close to the bronx. very corrupted. works for me though.

 

[Camo]

The smog block off plates will stop the popping.

 

[kononovitchpavel]

thats what i did. gutted the cat on my wrapped headers and brought and nice oem set with a o2 of ebay for smog.

best way to take it out is to cut the end off when it takes like 15 mins to beat it out. you just need to have a welder to put it back together.