Quote:

I have been puzzled by the fascination with airbox mods when the valve lifts-durations-overlaps are the limiting factors with the 900's



Don't be puzzled...it's really simple. Not everyone here understands engines well enough or at least don't know the cam in the 900 is the limiting factor. I suspected it because as far as i know thats the main if not only fifference between the 790 speedy and the 865. but i didn't know that it would render extra airflow useless.

So this brings me to another question . If the cam really is the bottlneck in this engine would a cam with NO bore kit make it possible to get the same percentage of performance boost out of the 865 as the 790 gets? If so, i might consider a cam down the road depending on hhow the pipes do by them selves. I'm not looking for loads more power, but i would like enough to make the bike run say 15% stronger. And i don't think the pipes will do that for the 865 from what i've heard. Also, if the can WILL make the engine respond to the pipes like the 790 does, will t also then allow the 865 to get more gains with airbox mods?