Losing Power on the Triumph Street Triple

Recently, when out riding my Street Triple 675, aka Peaches, the mysterious engine light turned on for the first time in 10 years. Yes it's true.

"Peaches", I asked, "what's up baby?" and rubbed her tank with love. She replied with nothing, but the engine light turned off after an hour or so of riding, so I thought she must be self-healing. Then a few days later, I was riding on a busy highway in 6th gear--it was a smoking hot day and boom! All power was lost. The RPMs dropped very hard. I shifted down to get some acceleration; nothing.

Shifted down to 4th; nothing. More downshifts and still no power. Luckily I was on a calm stretch of road with few cars on it so I coasted over to the gravel shoulder with the engine running as if in neutral. I turned the engine off. Then after a few minutes, I switched it back on and started her up. Peaches was up and running! But the engine light was back on like an ominous visitor at sunset. I continued riding but kept her out of 6th gear, just in case.

Strange one. 

Once home, after about 500kms of worry-riding, I did some investigating and it a few things came up… 

• Maybe it was due to running a lower grade of gas, I did lose power after filling up on some cheaper gas
• Maybe the root cause was due to overfilling the gas tank and creating some kind of a vacuum that causes the ECU to freak out
• Or maybe I needed to get the code read?!

I booked an hour at Studio Cycle, my local motorcycle shop, to hook up Peaches and have Diego read the codes for me. It was the barometric pressure sensor that needed to be checked out and cleaned (what else can you do?). It was not easy to find. It's situated on the left hand side at the front of the rear mudguard beneath the seat. The barometric pressure sensor measures atmospheric air pressure. With this information the right amount of fuel per injection is adjusted to suit the current air pressure. Loss of power had something to do with not reading the current air pressure correctly. It's a bit of a mystery.