Trophy Old Trophy 1200 Fuel Problem

Pilot jets are favorite

 

Is it always the same cylinders? Check your leads too.

 

On the bottom of the carbs are some screws which will allow the fuel too run out, That way you will see if any particles in or if it is going through

 

Stick some Redex, or similar, in the petrol for a few tankfuls and ride it like you stole it (ish). That should clear the carbs out if that is what is needed.

 

When did you last drain the carbs & tank, all of my recent bikes ( Trophies ) have had an accumulation of water in the bottom of the tank, the last one had 2.5 L caused one or two odd starting an d running issues before I removed the fuel tap, drained and cleaned / refilled with clean fuel

 

Go to the pilot jets, next to the main jet.

 

Could it be the crank pick up sensor for the ignition ?
Sometimes they can fail and cause intermittent problems.
I`ve seen on here others having problems with them.
It`s part No 1 in picture.
Others on here might have more experience of this on forum or more information

 

Crank sensor failure would affect all cylinders equally and 99% of the time is all or nothing.

The symptoms would point to a fuelling fault rather than an electrical issue, and removal of the tank to change coils etc is enough to disturb / reset the fault, the other thing to look at would be the carb vacuum caps on the carb tops for presence and splitting / leaks, also check the vacuum line to the tap from the carbs ( usually from no 3 ) and or pinched / trapped fuel lines.

 

They have a problems with the pipes deteriorating (Fuel lines}

 

I own an 03 triumph trophy 1200. The fuel vacuum line that has/needs a 90ﾟ angle. Because it rubs against the frame and cracks. The vacum fuel line on the petcock to the #3rd carb. That fuel line kept cracking rubbing against my frame. After 8 months of this happening again and again. I replaced it with a 5/16th ID yellow weed whacker fuel line. Where it bends at the petcock I used to shrink wrap and heat to bend it Into a 90ﾟ so it wouldn't kink. Sloved that problem. FYI any overheating problems. The sensor in the radiator goes on at 100ﾟC. Which is a boiling point. I replaced it with a Standard sensor TS266. It turns on at 94 Celsius before it boils. All my overheating problems went away. I did do all the things you did thinking it was electrical. But every time I pulled a tank I notice the vacuum line to the carburetor from the petcock was cracked every time.