We first this 1999 Yamaha R1 at the end of September, when the owner called up and to book the bike in for the carbs to be set up on the dyno.
The owner had fitted a Scorpion silencer and wanted to make sure that the fuelling was correct but while it was on the dyno, we noticed that it was not making great power, only 125 bhp.
The exup valve was a common problem on the early R1’s, they often were not serviced properly, so our advise to the owner was to try and get a full system, to do away with the pesky valve.
That was easier said than done, as a lot of the companies that produce exhausts, do not make anything for this model but a man in Greece had a full Arrow race system for sale, so the owner snapped it up, and to complement that he bought a BMC race air filter and new carb repair kits, so we could do a proper job.
Now 18 years ago the bike made 138 bhp on the dyno, after having the head ported/polished and a squish head gasket fitting and today with all the adjustments made, the result was good 149.71 bhp at the rear wheel with 79.27 torque.
Not bad for an old girl!