How many out there are so well tuned they can reach for WOT from a dead stop? And just hold on then and climb through your rpms – without bogging or gasping? No feathering of the throttle to get thru those rough spots?
I'm getting close with my latest build, but admit each of my other 3 bikes call for a little wrist work here or there.
I'd say 90% of the time, I can.
If it doesn't, theres usually something internal.
I've seen 5 or 6 heads in the last 4 months that had leaking valve seats. They still started and ran, jus low on power and sluggish, no tuning could fix it.
They were OHV clone heads, and lapping the valves solved the problem. Some took more time then others to get seated.
I'm working on a head now thats got SS valves in it. I think the valves have really messed up the seats. I got new stock valves coming, but I still think both sides will leak. It's ashame the customer had the head shaved and some other work done to it last winter, now the seats need replacing.
I put a used 20cc head on it and it hauls the mail and more. But his fancy, high dollar head is way down on power and all it is, is the bad seats.