Engine not hitting rev limiter

It's my believe that every toolbox should have a good quality comppression tester. (Pep Boys doesn't sell one)

Test yours, test your buddies, find out what's good and what's bad. After you break in a rebuilt engine, start testing it after every race, write it down. It is my contention that; compression "is" the Holy Grail.
 
alvin l nunley said:
It's my believe that every toolbox should have a good quality comppression tester. (Pep Boys doesn't sell one)

Test yours, test your buddies, find out what's good and what's bad. After you break in a rebuilt engine, start testing it after every race, write it down. It is my contention that; compression "is" the Holy Grail.
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I would normally agree with this 100% but in this case a 206 has a compression release for easy starting. In this case a leak down test would tell you if the valves are sealing. To the OP also check the pilot jet.
 
I'm no LO 206 nor an engine guy for that matter, but seems to me as long as your hitting your target RPMs who cares if it doesn't hit the rev limiter, am I missing something. Also are you sure your gearing is right and your just not turning it enough ?
 
No doubt Al is aware of both pull start and compression release. He's likely expecting the guy doing the test to spin it fast enough to get a meaningful result. I too believe in compression, and when it starts to go away it's time to leak it and find out why. My 2 cents.
 
Unless the valves are leaking something atrocious, it's not your problem.
Springs are even less of a problem.
Clean your carb thoroughly. I suspect at inlet needle sticking wide open causing he carb to run full rich.
Head gasket, if bad enough, could be the culprit as well. As mentioned above, a leak down test is the appropriate way to check for this.


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racing promotor said:
I'm no LO 206 nor an engine guy for that matter, but seems to me as long as your hitting your target RPMs who cares if it doesn't hit the rev limiter, am I missing something. Also are you sure your gearing is right and your just not turning it enough ?
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Ken, back in our 206 days, the limiter was our target rpm, acting like a brake :)
 
I finally gave in and bought a leak-down tester a couple years ago. It's one of the best diagnostic tools in my shop! In a couple minutes I can tell if it's valves (and which valve it is), rings, head gasket, etc., that are leaking. Way more effective than a compression tester - on any four cycle engine, not just karts.
 
i had this issue last season. put it on the stand and rev it up. if it hits the rev on the stand its the kart not the motor. Mine hit the rev on the stand. when on the track my kart was binding up on the last corner before the longest straight.
 
I had the same issue of being 200-300 RPMs short of the limiter, but hitting full RPMs on the stand. I had the valves redone and now I am pack to full power. My guess is that a valve wasn’t fully closing, either from a weakening spring or needing a small lapping.
 
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