I have a1995 Lakota KEF300A that intermittingly will run great to half throttle but above that rpm level will bog down and backfire. About half the time it bogs down at above half throttle but about half time it runs great all the way to wide open throttle. I checked the voltage regulator and it was bad so I replaced it. About 80% sure it's not carb related. (cleaned and adjusted already) Thought it might be CDI. Any suggestions would be appreciated

 

Putting higher voltages than 15v through the igniter (CDI) does it no good at all, so it may have been damaged by the faulty regulator. However spending $431 on a genuine igniter unit and then finding it isn't that at fault, is not the way I would chose until I had eliminated everything else. If you can swap parts from another bike it makes the substitution method a lot cheaper. Faulty regs also can damage the plug, have you swapped it?

 

Thanks Merryman. Yes, I have replaced the spark plug with new. This is one of those dreaded intermittant problems. When it runs correctly (about half the time), it runs great. No backfiring nor bogging out. Then about half the time it will run correctly up to about half throttle, and above half throttle it bogs down and backfires. At times, I have been riding it and works fine at upper throttle and then it bogs down and backfires. Almost like a loose wire/short. Very strange