I have a 81 A/C Pantera 500 spirit engine. This stupid thing seems to foul both plugs like crazy. The carb has been cleaned and recleaned, checked for leaking crank seals & carb boot, rebuilt fuel pump and tried a different fuel pump, and unhooked vacuum line from crankcase to clean out any fuel in the case. I have no other idea or areas to look at. ANY SUGGESTIONS??

The throttle cable also sticks on this old girl. I thought the cable was freyed and replaced it with an oem cable, but no fix. It has a 34mm Mikuni roundslide. When you put the slide into the barrel it doen't want to "slide" down very easy. When the throttle cable sticks you can wiggle the cable and it will unstick. You can hear the slide free up and "bottom out" in the barrel. I think I have tried everything except burning it to the ground. Any one have any ideas??
Thanks.

Fouling Plugs? How is your oil mix? What ratio? Have you tried changing plug brands?

Sticking Throttle? Lube the cable up and all linkages / moving parts.

Unscrew the top where the cable goes in. Remove the spring & cable. The slide should slip in & out easily. Cutaway faces back towards you. If the piston still sticks, is the needle bent? some obstruction?

Is there a nick or dent on the slide? It has to pe perfectly smooth or it could cause the sticking problem.

Make sure your oil pump is working properly, if it's too rich it could be causing the fouling.

MOD

Thanks for the replies. I had this same post on another site with not even one reply.
I had cleaned and lubed the cables and all moving parts. No luck. I always run NGK plugs and have had very good luck with them. I am going to replace needle and probably the piston in the next day or so. I might try unhooking the oil pump and pre-mixing the gas. I will let everyone know what happens.
Once again thanks for all the replies. I had much better luck on this site than the other one.
Thanks again.

PROBLEM SOLVED. I hope. The slide must have had a bur on it. I took the finest micro-file I had and filed the "slot" or "keyway" on the slide. Put the thing back together and it works like butter. I also checked the synchronization of the injector pump and it was way off. I think you hold the throttle wide open and align the timing marks on the arm and the pump and adjust accordingly. Please correct me if I am wrong. But this seemed to make a world of difference. Good throttle response now.
Thanks to all who replied. Your help was appreciated.
Thanks again.
JLH

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You should be good to go, enjoy the sled.....I remember my uncle having that exact same sled when I was a kid.

MOD