Removing catalytic converter

[NDORFN]

Anyone know what results this may have? It's a an EX250. Please, no comments on environmental impact etc... it's a bike, not a hummer.

[YellowDog]

You'll need to get it retuned for the new non-cat exhaust that you will have created. I am sure that $50 will more than cover it on a modern bike as you have. You may also need to change the airfilter to one that will pass air at a more rapid rate (maybe not).

It will probably give you a couple more HP, depending upon the retune.

[NDORFN]

I'm not after more power, just more noise! I'm used to riding quite a bit by sound on my old bike, especially down changes, and it's a bit tricky when you can barely hear it. Suppose removing the catalytic converter won't make a difference and leave me needing a re-jet?

[jono035]

I'd think that the lack of back-pressure from the cat would change the engine tuning so you'd need to be careful about what happens mixture wise, worth checking at least...

[pritch]

It would be more simple on a bike with a carburetor.

Otherwise it can be an expensive proposition: in my case a full exhaust system, Arrow or Termignoni, a free flow airfilter, and a new chip for the ECU. Might have to get used to the cat.

The sound is OK, I just don't like the look of the thing. Or where it is.

On any injected bike the minimum outlay would be a PowerCommander and a custom map. There goes about a grand...

[NDORFN]

It would be more simple on a bike with a carburetor.

Otherwise it can be an expensive proposition: in my case a full exhaust system, Arrow or Termignoni, a free flow airfilter, and a new chip for the ECU. Might have to get used to the cat.

The sound is OK, I just don't like the look of the thing. Or where it is.

On any injected bike the minimum outlay would be a PowerCommander and a custom map. There goes about a grand...

It is carbed. Funny thing about the new EX250 is that it's almost exactly the same engine as the old GPX250. Infact, the only significant difference is self-adjusting valves.

[classic zed]

Google is your friend, this might help.

http://www.car-techie.com/converter.php

[jono035]

That article covers an EFI car engine not a carburetted bike engine.

EFI engines have the ability to (while running in closed loop mode during idling/cruising/light acceleration) adjust to changes in the intake/exhaust system, but these may still cause issues in open-loop operation (cold running and full throttle) if the maps no longer keep your engine as rich as they should...

[awa355]

Have just picked up on your thread from some months ago. Did you do anything about removing the converter? I have a single cyl Honda 250 with the same problem. It is a carb model, I dont want more grunt, just a nicer exhaust tone.