Weird power loss

[notagix]

I was out for a ride, cruising along at about 110 kph, it felt like it started to miss on one cylinder, then lost power. I pulled over shut it off. Waited about 30 seconds, fired it up and it was much better but the fuel economy was poor according to my dash display but otherwise ok. I got to my destination turned and headed home. On the way home gas mileage was poor, again according to dash display, about 150 km later same thing ,loss of power then like hit a switch and power came back. Any insight on this would be greatly appreciated. Thanks in advance.

 

[acedantinne]

bad fuel. I just had the same problem. Riding home from Vermont camping trip. Low fuel 2015 BMW R1200RT. Fill tank at Commuler farms station rt8 Mass. in N Adams. Mid grade. All the way home bike did not run good. Felt like 1 cylinder was cutting out. Throttle response was poor. Back firing through exhaust, stock exhaust system. ever time U backed off throttle.
I know fresh gas will fix this problem.

 

[notagix]

Acdantinne, thanks for the reply . I doubt it is that, it happened again after I fueled up at a different station. I should elaborate, it's a 2005 ST 1300.

 

[Esti1300]

I had a similar problem that turned out to be a loose ignition coil connection.

 

[jfheath]

Just in case - if it happens again, lift the fuel tank lid. It may be developing a vacuum. If it is, the frequency is likely to increase after refuelling as there is less air in the tank to start with.

Also check your water overflow pipe is clear (left hand side of filler neck). If it isn't then when it rains you may get water surrounding the neck so that when you open it, it overflows into the fuel. No problem there - it will sink to the bottom - but eventually, there will be a pool of water down there which is being sucked up with the fuel.

Not sure that would explaing the backfiring. Duff HT leads and plugs would - if it isn't sparking every time, unburned fuel gets shoved out into the exhaust gets ignited with a bang a little later. Also split vacuum pipes to throttle bodies - five way tee might - I know the vaccum tuned on the ST1100 cause this behaviour if one is leaking. But ST1300 isn't the same setup.

 

[dduelin]

I had a similar problem one day with my 2005 ST. It would be running fine then lose power like a switch was thrown. It wouldn’t quit but felt like it was running on two cylinders and as a fact when I pulled over to look things over one of the mufflers and catalytic converter was heavily oxidized to the gold/brown color they get after thousands of miles but this happened in less than 20. After a few minutes it regained power. I think it did this three or four times. I was 150 miles from home and I decided to try and get it home as long as it kept running. In my case it was fixed by replacing the coils. One coil was cutting out and I surmise that unburned fuel/air mixture in two cylinders on that side went through the cat where it probably ignited and overheated the cat. The bike would run but very poorly and gas mileage in the dash dropped to the teens or low 20s in mpg. I never knew if a coil was actually failing or the low voltage leads to the coil had poor connections or corrosion under the coil mount was to blame.

 

[notagix]

Thank You guys for the replies and suggestions, I won't be able to check it out until next week.

 

[Chris09]

I've been hammering my 09 ST around lately to see if I can repeat the [similar] problem I have with another [Honda] ECM and it's not happening; from what I understand, the ST iluminates at 4,000 rpm and the blackbird at 5,000 rpm. But, to be fair, I've been riding the ST around 7500 to 9000 and I can't make any problems; so maybe...

 

[Chris09]

which is well over the ST 8500 redline, so I think it's all BS

 

[dduelin]

which is well over the ST 8500 redline, so I think it's all BS

The US spec 2005 ST1300 can freely rev to at least 9350 rpm before the rev limiter steps in.