Predator 212 gen 3 problems

[Bier84]

I guess I will start with describing modifications.
I have a predator 212 non hemi 3rd Gen with 22mm mikuni carb/black mamba adapter , fuel pump , 18lb valve springs , header , rlv silencer, billet flywheel , dyno cam mod 2 cheater cam ,valve lash setting at .002 on Intake and exhaust , hillard clutch set for 3000 rpm engagment , Governor removed. Plugs not fouled, carb is jetted just right. When the motor warms up it will not rev past 4800 rpms with no low end torque. When it's first started it will run 7500 on a pass.???????I've tried every thing.

 

[Bbqjoe]

This is the engines way of preventing you from going too fast, and killing yourself.

Valves floating?
Spark plug failing under heat?

Someone with something better than guesses will come along soon.
For best results, DO NOT START ANOTHER THREAD ON THIS TOPIC.

 

[gman3850]

Over the years I have owned my aircooled bugs I have ran into this issues 3 times. Unfortunately they were are due to heat causing havoc on parts. Twice it was my ignition coil. Would operate fine when cold but on hot days car would cut out and sometimes not even run. Took me about 3 weeks to find the problem. Second time I just pulled coil and got it warranties and all was good. The third time it was vapor lock. Again the hot summer of. As and a blocked vent caused fuel starvation when hot.

So for you I would double check your cam timing. Also I guessing your compression ratio is stock but at a 32 degrees timing I would still recommend 91 octane to prevent detonation which causes more heat

 

[Flyinhillbilly]

https://karting.4cycle.com/showthread.php?82670-crazy-S-A-motor