86 Interceptor 500 Starting Issue, possibly a fueling problem?

I have bought a 1986 Interceptor 500 and it has some sort of starting issue. When it is warm, it starts well. There seems to be no problem. However, when it is cold it is very hard to start. It starts, runs for a little while and then gradually dies. However if I use the choke, and by judicious very small throttle movements, it may be able to be got running.
I am reluctant to start disassembling anything until I have a better idea of what may be the problem. This model has no fuel pump and appears to have no lines going to the fuel tank other than that which is connected from the tank to the carbs to delver the fuel.
I wonder if anyone here has any idea as to where to start looking.

Thanks

 

It's very common for the long brass tubes that supply fuel to the enrichment circuit (aka, choke) to develop clogs, making cold starting difficult. You'll need to probe the holes with a thin (.012") steel wire to a depth of about 30mm to be certain they're clear of obstruction.

 

Thanks for this answer. So the carbs have to come off then though. At this point is it worth taking them off and running them through an ultrasonic cleaner?

 

Has the bike sat for any length of time? If so the carb will get gummed up and needs to be cleaned? Cleaning a carb is fairly easy if you have not done it before. It will be more work getting it off and back on. The results will be well worth it though. Also plenty of people on here willing to help walk you through it. Welcome to the site by the way

 

What those guys said...
You have to pull the carbs and do a complete cleaning. A lot of the hard starting issues can usually be traced to the pilot circuit so you want to spend a lot of time making sure everything there is clear. You can clean the pilot jets but for $6.00 ea it might just be easier to replace them. Also, they may be the incorrect size. When I pulled mine out they were one size smaller than stock (for altitude, I guess). I put in stock pilots and it helped tremendously.
While you are at it you should check you choke cable operation. Mine does not pull the enrichment "knob" out far enough. I have not quite figurd that issue out yet.
Good luck,

 

Try adjusting any excess freeplay out of the cable at the threaded tube under the left handlebar switches.

 

thanks for all the replies. I guess I am going to get intimately acquainted with the carbs on this bike.
Whilst I am at it, another query then. On turning on the ignition, the cooling fan immediately starts. I surmise that this is not normal. Perhaps the thermostat is stuffed, any ideas?

 

I have never owned the 500 so I can't say for sure. But no it doesn't seem normal that the fan kicks on immediately. Now if the bike is still warm from just riding it then I could see it coming on first thing but not when the motor is cool.