The owner of this 50,000-mile XJ600 brought it in along with a Power Commander PC V; he’d also got a Dynojet Autotune to go with it. Now he does something like a 140-mile a day round trip commute and was looking for improved economy.

We wouldn’t fit the Autotune. It can be a useful device but on a day-to-day commuter bike serves no real purpose. Setting them can be finicky and you have to stay on top of ‘em – one setting does not cure all. So we told him to take it away and sell it…

Fitting the PC V was straightforward, and we built him a fuelling map to match his mostly motorway/20mph town traffic daily ride. He felt he wasn’t getting decent cruising speed economy and the bike ran lumpy in traffic, so the worst of both worlds!

In all honesty this was a hard call to get absolutely spot-on and we’re having the bike back to see if we can improve the fuel efficiency further…

Now this bike does some work – 140 miles a day to be precise. It's now got a PC V setup, but is coming back for further tweakage...

Now this bike does some work – 140 miles a day to be precise. It’s now got a PC V setup, but is coming back for further tweakage…