Intake ports

First time post on here, though I have been reading this forum for a couple months while getting my bike running again. I have an 81 750 Seca that has sat for about 15 years. It ran fine when I put it in storage, just needed a paint job that never got finished. So I took it to a local shop to get the carbs rebuilt, since I didn't really have the time and if I can't fix a carb problem with a can of carb cleaner I can't fix it.

So now it's running again and the only real problem is that after it gets warmed up really good I have the creeping idle problem. When I pull up to a stop it wants to sit at 3 grand or so and I have to use the clutch to keep it down. When it drops down to about 1500 it will sit there for a bit, but then want to start creeping up again.

I thought maybe the issue was the intake boots on the engine side, since they have lots of cracks, but I have done the carb cleaner with the engine trick and it doesn't affect engine speed. I should note that after I start it and warm it up a little it runs great and idles where it should, only after I ride for a while and it gets hot do I have the idle probs.

So today I got ambitious, pulled the carbs, and removed the boots. They are thicker than I thought, and the insides look fine, but I plan on using some high temp permatex rtv silicone gasket maker on the cracks. The problem is that when I got the boots off, (lucky me, all the bolts came out just fine ) the ports on the engine have a lot of carbon build up on them. The far right port isn't as bad as the others, but still has a little.

So is this normal, or should I be concerned? Should I try to clean the ports or will I cause more problems? Could this be an indication that the gaskets on the boots are the problem? Should I get stock replacements for the gaskets or is there a better option? They are thin paper gaskets.

Thanks for any help.

 

Scratch that, they aren't paper gaskets, just looked like it when I first took the boots off. They are some kind of hard material and they look like they are in ok shape. How are people cleaning them up and sealing them again?

 

I cut replacement gaskets out of cork/rubber gasket material.

 

They were paper gaskets before they were compressed then petrified by heat.