Open Airbox + Stage One Carb + Stock Pipes

[dropstharockalot]

I bought my used '96 M900 with some pretty hot mods - open airbox, K&N air filter, K&N Stage One Jet Kit, emissions equipment removed, hot coil plugs and wires, and home-made cored and shortened mufflers.  It was a beast, as you might expect.

The problem was it was too damn loud.  Squirrels would fall out of trees when I'd twist it a little.  I was attracting the wrong kind of attention when I'd ride... like the kind that wants to see my paperwork and discuss my rate of travel...

My solution was to hunt up a set of stock pipes and bolt them on.  I had an immediate impact on the volume, and the sound is much more subdivision-friendly at this point.  Performance wise, the beast is a bit more tame, but there is still plenty of grunt anywhere I want it - I knew there'd be a small performance penalty, and I'm ok with that trade-off.

My question is this - are there any long-term ill effects of running this setup?

Thanks in advance.

[ducpainter]

I'd keep an eye on the plugs.

If they're not white from being lean, or black from being rich you're good.

[scott_araujo]

I'd keep an eye on the plugs.

If they're not white from being lean, or black from being rich you're good.

+1.

Scott

[ScottRNelson]

In my experience, the pipes don't change the engine performance much.  I've tried all combinations of stock airbox/jetting and open airbox/jetted with stock pipes and Ducati Performance slipons.  The bike only sounded faster with the DP slipons.

Personally, I prefer lightly modified stock pipes with the tubes cut out of the rear chamber.  It sounds more like a proper Ducati, but not nearly as loud as with slipons.  Still no noticeable change in performance.

[dlearl476]

I'd keep an eye on the plugs.

If they're not white from being lean, or black from being rich you're good.

+1

I would suspect that adding a more restrictive exhaust makes you run a bit rich.  Less immediately harmful than running lean, but it won't run right forever than way.  (fouled plugs/carbon buildup) You might want to put a post in "Parts wanted" for a set of OEM jetting.  I'm sure a lot of them are sitting around.  I'd  give you mine, but I'm saving them to sell with my OEM carbs when I finish my FCR install.

[dropstharockalot]

ducpainter: I've got a set of stock carbs with stock jets and I just haven't done the swap yet.  I was waiting to see if the responses were going to warm me of immediate danger of horrible damage to various expensive engine internals, but that doesn't seem to be the feedback I'm receiving.  At this point, I think I'll monitor the plugs as suggested and ride the bike as-is.

All:
Thanks for the input, and if anyone has anything else please post that as well.  The advice is very much appreciated!

[brad black]

i run my 750 like this.  i have a suspiscion that the std mufflers lean them out a little, but i don't think i've ever done back to back datalogs to see if that's true or not.  problem with the dyno is that the std mufflers block a good sample that much that what you get is often not useful.

the mufflers really hurt the power on mine, especially the midrange.

i'll try to get a couple of logs done sometime.