Can anyone think of a reason why...

[Cher]

It is my understanding that removing the catalytic converters will not affect the engine's overall longevity since all the changes are taking place on the exhaust side of the engine.  

Would the engine's performance be reduced without also improving the engine's ability to breath - like by adding a high-flow air filter or re-mapping the ECU?  I'm certain it would.  But improving engine performance is NOT the goal with my exhaust mod idea; all I want to do is substantially reduce weight.

The heaviness of the stock exhaust on a 999 is unreal.  I'm not entirely sure since I didn't actually put the part on a scale, but if the exhaust canister weighs LESS than 25 lbs, I'd be amazed.  And, unfortunately, this big chunk of weight is absolutely in the worse place possible when hustling an already porky motorcycle around the race track - up very high and basically cantilevered off beyond the rear axle centerline    There's no doubt in my mind why the aluminum subframes on the mono get stress cracks and break.

Now I'm sure this imbalance could easily be shrugged-off by an experienced rider, but I'm not.  So I'll take all the softballs I can get while I develop my skills.

[junior varsity]

Performance would not be reduced by removing the exhaust but not adding the high flow filter.

You'll get some benefit from removing the stock exhaust and replacing it with something better flowing, without ever touching the intake or the ECU.

Reprogramming the ECU and or getting a high flow filter would improve the performance further. It'll also correct a slight lean-running condition the freer flowing exhaust will create. However, I haven't read anything that shows engine damage from running aftermarket exhaust without tinkering with the other stuff. The change isn't that significant, regarding flow, the big changes are in weight and sound level (decibels)

[junior varsity]

For note: the stock monster pipes on the DSS monsters weighed a ton. It was ridiculous. They would have made for a good cricket bat, me thinks.