T509 Ecu Issue

Hi and welcome to the forum.
Someone may be able to throw some light on this for you.

 

Hi Rich and welcome in to the Triumph Asylum.

Re your issues, when cold the bike is designed to tick over at a higher engine speed, so on the face of it, nothing very unusual about that. Do you start the motor and ride straight off, or do you leave it ticking over while you get your gear on?

Re the fan business, these engines have a tendency to run warm, so again nothing very unusual about it staying on after you've turned the engine off - 90 secs is a bit long though. Have you checked the quality and level of the coolant?

 

Welcome to the forum Rich.
Could it be a sticking throttle cable ?
I don't know about the ST but my Bonnie EFI has a manual 'choke' although it's not a choke, if this was sticking it would raise the revs ?

 

Sounds like it could do with a good service, plugs, air filter, throttle cable adjusted, carbs balanced, or has it got a good service history?

 

sounds like there is a pipe to the throttle bodies may be split or off sucking in unmetered air flow causing the 3k fast idle

 

Do these bikes have an IACV (Idle Air Control Valve) if they do, then a sticking one will cause the high idle.

 

I have had my T509 for 20 years and 63000 miles. I haven't used it for three years, and even then it had become the spare bike. the last few years I was running it I had similar problems with idle speed, tick over was controlled by blocking the hose to the IACV but it ran rough and stalled a lot.
I did all the stuff above, dismantle and clean and test IACV, new hoses ( its the little loose ball non return valve that needs checking. new gaskets on the intakes, fuel injectors sent off for clean and testing . I put off doing a TPS reset (throttle position sensor) because I was frightened of mucking up the ECU. Times change and I hooked up the laptop and was amazed at the transformation.
the software is free and a lead is cheep and can be used on lots of other vehicles.

I am now having a different but associated problem. over the past year the fuel has gone rotten. everything was choked up with rusty slimey gunk.
I fitted new fuel rubber hoses inside the tank as they have swollen and popped off the fittings. I cleaned everything again. it was running like new!
But I left it a few months again and the fuel went off again blocking the fuel pump. I dismantled it again ( getting quick at that now) fuel is flowing engine starts but itis running at 6 to 7000 revs, while fiddling I found that wobbling the handlebars affects the speed of the engine. This is not a throttle cable issue.

Does anyone know how a wiring fault in the handlebar wiring can control the engine speed?.