St1300 intermittent loss of power help needed

970mike · Nov 26, 2014

Did you replace the gasoline with new fresh gas? My thought now is that you may have some old gas in the system, put some SeaFoam in the tank with fresh gas and give that a try. I am assuming there are no blockages or pinched fuel lines in the system.

mean13 · Nov 26, 2014

The reserve tank may have gunk or trash in it. It may be clogging the filter after a little while. When you kill the motor, some of the debris falls off the filter. As you run it clogs up again. Next time you have the bike apart pull the pump and inspect the lower tank. It happens in cages, so it might be something to look at.
:tb1:

Simmo50 · Nov 26, 2014

I checked the filter , no debris very clean, it seems to be when something is getting to a certain temperature, then when you let it cool down for a while it cures the problem, until it gets to that temp again

BakerBoy · Nov 26, 2014

Sorry to hear it's still acting up Simmo.

From what I can interpret from your couple posts, my next suspicion is the coils. As Dave posted in #19, the coil mounts/connections can appear fine but can lead to such problems. You can also check coil winding resistances (instructions in the service manual) to ensure both coils are 'normal'.

dduelin · Nov 26, 2014

Simmo50 said:
Ok , I'm really getting annoyed with this problem now, have replaced the fuel filter, fuel pump, and spark plugs,

when I did this the bike was wonderful , for one day, thought my problem was solved.
then next weekend I went out and after an hour of riding, it started to play up again,
I'm losing all confidence in this bike now, I'm scared to go on any long rides in case it breaks down,
had a quick look at the coils, and they looked good, not rusty or anything, no loose wires,
what can I look at now.

I'm sure you did this but .... looking at the coils and tugging on the small gauge wires isn't enough. Remove the 8 mm bolts retaining the coils to the frame and inspect where the underside of the coils make contact with the coil mounts. A small amount of corrosion here, in particular the right side, presented similar problems to me.

Simmo50 · Nov 26, 2014

Will check this out tomorrow and let you know , are the actual coils known to pack up on these bikes at 32 ks, I don't know why when I turn bike off for about 15 minutes it goes ok again for a while, then comes back

Mellow · Nov 26, 2014

Might be the air temp sensor on the top/back of the airbox but I believe that usually throws a code. Almost sounds like a pinched vacuum hose but based on what you've done so far I think you would have noticed that.

CYYJ · Nov 26, 2014

This is just a shot in the dark, and might be not applicable to the 1300, but:

About 5 years ago, I encountered a similar problem with my ST 1100. Turned out it was a problem with a fuel shut-off valve that is (somehow) vacuum activated. I disconnected the fuel lines from that valve and plumbed them around the valve, and that solved the problem until I could get a new valve installed. I don't know if the ST 1300 has a similar fuel shut-off valve or not, perhaps others can answer that question.

Michael

BakerBoy · Nov 26, 2014

No, it doesn't have a fuel shut off Michael. The absence of fuel pressure from the fuel pump means the injectors can't deliver fuel.

Igofar · Nov 26, 2014

Have you inspected and cleaned the 5way tee and replaced the hoses?
It won't always throw a code.

St1300 intermittent loss of power help needed

970mike

Mike Brown

mean13

Simmo50

BakerBoy

It's all small stuff.

dduelin

Tune my heart to sing Thy grace

Simmo50

Mellow

Joe

CYYJ

Michael

BakerBoy

It's all small stuff.

Igofar