One 2002 Hayabusa, fitted with a full Yoshimura exhaust and K&N filter. Its owner was complaining of low speed running problems – this bike was too old to have lambda sensors fitted, but was running poorly because of the different airflow and lower back pressure from the filter and open exhaust.
A Power Commander PC III was a straightforward choice and fitment to sort this bike and out, and these engines respond beautifully; it needed fuel in the midrange, which we dialled in. It left our workshop with a 6-7bhp bulge over a wide rev band, and much improved throttle response.
Free breathing inlet and exhaust mods messed up this 'Busa's bottom end; a PC III sorted the job.
