And suck it, it was.... The dyno side of the our NSR program decided to find out what the real story was with the air bleeds in or out of operation, as I'd been going mad with not finding any info...... yeah, surely you guys with all the stars must have known this anyway and were keeping it quite... So an MC21 on the dyno with open carbs, big jets, tyga pipes and solenoids set up as factory. X.3 h.p.@ 12,500 rpm.
Same MC21 set up,same jets but with JHA chambers and the solenoids set up as factory.......X.0 h.p. and only 12,000rpm

I'm not telling what the real figure were but the story is pretty plain to see. The JHA's made a bit more mid range from 8,000 than the tyga's.

Off with the air bleeds and plug the lines... shite... and then with some normal main jets in the bleed lines, and after several runs from smaller to larger and then back again we have these figures to consider. Tyga piped MC21... X.3.3.h.p.@ 12.500 and the JHA's giving ...X.1.h.p. @12
So the carbs will run very well indeed without the air correction solenoids by placing a 140>150 main jet in their place. But the real surprise was the mid range gain from 8,000 rpm to 10,000 rpm where the JHA pipes made an extra 2 foot pounds of torque. This was also reflected in the Tyga pipe mid range, 1.8 flb and as the Phantom of the dyno said...made very angry motor.

Well that's it, the truth's now out there, whether you want to use this info, or whether it suits your riding environment, who know's but as racers it is really good news for us NSR production racers. Cheers Jeff