Hans, I did use the 91, it seems to lesson the chirping but not eliminate it. I did think the chirping was a little worse when the motor was cold and only very slight when fully warmed up but as all the riding was highway riding I can't be sure but I had great day out.
Im sure the filter assy will offer more restriction and larger loss of HP on say my modded Carpenter 250HP bike because of the of the higher volume of air needed for the free breating engine
I think to be fair RAMAIR is too. There was talk of a high volume filter with bespoke claw for monster engines if demand exists to make it worthwhile - ROI matters..
I balanced the throttles, all three on 620 then finally got out for a ride today, 350km round trip. The bike certainly performed well across the entire RPM range that I use.
The air induction noise would be a little annoying in city riding as would be the chirping, only experienced the chirping at open throttle around 2000RPM.
I might try some noise reduction material on the underneath of the bar claw.
In all the RAMAIR suits me
Thats not inducton noise your hearing its mechainical parts. The squirels ar enot chirping (or what ever varmets you have down under) its the noise created by power! the only way to quiet that and create power is Forced Air so get used to it or nuzzle the beast back down to what OEM did
Im sure the filter assy will offer more restriction and larger loss of HP on say my modded Carpenter 250HP bike because of the of the higher volume of air needed for the free breating engine
What filters are you currently running to achieve 250HP? and as Neville Lush has already stated the Ramair would be suitable for a standard or mildly modified motor (exhaust and mild cams) if you want keep t all under a uncut bear claw, any more would require
Larger Filters eg 1770 or 4040 ........... your 250HP bike is producing those figures up at around the 9,000rpm is it not? ... so it is well beyond the design brief of the Ramair filters so yes you will lose HP
Battersea's original design - subsequently made up by ITG would almost certainly replace larger filters like (say) 1770's or 4040's. The problem however was space - i.e it would not fit under the claw. If memory serves it was the bloody scallops (the spaces between the bears toes) in the claw. It was also MUCH more expensive - iirc Cost price double the retail price of RAMAIR.
I'm sure if we gently cajoled Battersea he could design and 3D model a filter with full size integrated elliptical bell-mouths that would fit on the throttle bodies and then somebody else can have it made up for high power motors - It'd make sense if it was somebody developing high Rocket power engines naturally. I'd put the ROI on tooling at about 500-1000 units given the complexity of the shapes.
It'd look pretty much like the filters Wayne Tripp was working on. In fact It'd be almost identical - and far more expensive than a RAMAIR. Would also require relocation of coolant bottle. But proven technology on 1000-hp race engines.