Hello Forum,

I am located in Halifax, Nova Scotia, Canada and new to this forum. I own a stock 2008 XB12XT with 25,000km (15,000 miles). The last 2 summers I have been experiencing - on occasion - a sputtering, loud puffing and loss of throttle when pulling away in 1st gear. By occasional I mean it happens say 1 out of every 3-4 rides. My response to this issue is to rev the bike (cutch in) high and then slowly release the clutch. Most times it will labour itself enough to get into second gear where it runs smoothly. In fact, it runs smoothly in all other gears at all other times.

I had a scare this summer where it sputtered, puffed and I lost the throttle power while trying to pull back onto a busy highway.

It feels and sounds like it is about to conk out or stall, so I rev the throttle high and try to pull away. This issue happens when the engine is cold (1 minute warm up idle) and when the bike warmed up after a ride.

This issue has me perplexed. I took it to my local Harley dealer and $300 buck later, they said o2 sensor "may" be cause (diagnostic) but they were not sure. Every time I have it looked at the bike behaves normally. Very frustrating.

Any advice would be greatly appreciated. I have some basic mechanical skills, but I would not be able to remove the fuel pump for example.

Thanks to all in advance.