Fouling Plugs 1980 XS400 Cafe

My son and I built a1980 XS400 Cafe Racer a few years back that hasn't seen much use since he's been away at college. The cafe build included installing pods and converting to Iridium BPR7EIX plugs with (IIRC) a non-resistive plug connector on the original plug wires. He's recently moved home and the bike has been used a bit more.

The plugs are fouling with dry sooty carbon (not oil fouling) on a semi-regular basis and the bike runs pretty rough until it warms up (this is nothing new, its been this way since the original build) . Generally, the complaint with installing pods is the bike runs too lean but this seems the opposite in that my understanding dry sooty plugs are an indication of running too rich. The carbs were cleaned meticulously a few years ago as part of the bike build and an inline filter was installed at that time but the carbs have not been cleaned since.

I'm looking for any ideas on?????

I would clean the carbs I just went through 3 sets today and even with virtually no miles since their last cleaning there was a large amount of varnish inside. These were cleaned last year before they were put away un November. Start there, they actually are quite easy to do. You don't mention any spe ifics for exhaust you have used, that will help you get the best information
Have fun!

If your putting a bike up for a long period of time (more than a month or son) drain the carbs. It will save a lot of headaches. If it's more than a few months drain the tank and fog the tank and motor. If you have a warm dry place to store them even better. Never leave ethanol based fuel in the bike for long periods of time ( month+) It will gel up and make starting very hard on impossible.

Petew said:

I would clean the carbs I just went through 3 sets today and even with virtually no miles since their last cleaning there was a large amount of varnish inside. These were cleaned last year before they were put away un November. Start there, they actually are quite easy to do. You don't mention any spe ifics for exhaust you have used, that will help you get the best information
Have fun!

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Thank you. The exhaust is stock.