The owner of this Thruxton has had it for some time, and after changing the pipe for an Arrow system felt it wasn’t running as sweetly as it should – and it was using a lot of fuel. We started by disconnecting the lambda sensor (he’d already removed the SAI, but we needed to switch it off in the ECU) and then remapped the fuelling.

And blimey, was it rich! Easily sorted. One thing we do reckon though is that Triumph dealers don’t explain that the pretend ‘carb’ body cover over the injectors is quite heavy and retains a lot of heat. So when these bikes are warm and switched off and on again, they go into a whole reset process which dumps a load of fuel in and puffs of black smoke out of the exhaust…

The trick is to pull out what looks like a choke lever on the injector body for about 15 seconds – it isn’t a choke but is a fast idle switch and sends the engine up to 3,000rpm. It’s nice and warm with oil around so it doesn’t matter, and instantly cures the over fuelling issue. The engine will now idle perfectly… start it without and it’ll cough, fart and splutter!

Thruxton a bit spluttery on start up from warm? Use the fast idle switch!

Thruxton a bit spluttery on start up from warm? Use the fast idle switch!