A couple of weeks ago I took the CBR over to Gary Pendleton for a dyno tune. Each time I've put a bike on the dyno I've gotten a great result and this time was no different.

Once again we'd gotten lucky with the ignition curve as not only did we find a few more horsepower we also cleaned up the power curve so it was no longer rough and lumpy, it was now much smoother and the holes were filled in. Usually Japanese sports bikes gain nothing from tuning the ignition but something on the CBR was different. Maybe it was because I'm running it on 98 Octane, or the K&N air filter, or the colder race spec spark plugs, or the Arata full Ti system. Whatever it was we made good gains from both fueling and ignition.

A couple of years ago I got hold of a dyno graph from another CBR 450 triple that had been on Gary's dyno. Comparing it with my bike I had about 1 horsepower more up to 11,000rpm, then 1 horsepower less up to 13,000rpm where mine then tailed off. The other bike kept pushing through to 14,000rpm, an extra 1000rpm that was worth almost 4 horsepower.

So that was the main difference between my bike - essentially a stock engine with a couple of injectors unplugged, PC3, ignition and air filter, and a bike that had the valves removed and some money spent on cams etc.

Seeing this sort of result pleased me very much. I haven't spent anything to extract horsepower other than off the shelf plugin bits trying, keeping the internals stock in favour of reliability and the only place I was losing out was too high up the rev range to do anything about without spending lots.

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