Harley XLHF Fatster 1st startup - without exhaust pipes :-D

[crackerhigher03]

Great way to drop a valve. 

[henkkaj73]

@crackerhigher03 Nah. Certainly it's true that you could burn a valve if you rode your bike without headers but letting the engine run at near idle for under 7 seconds is not going to do anything to your motor, I've now put about 20 thousand km on this baby and it still tops around 200km/h with both me, missus and three huge bags full of gear.

Nevertheless, a worthy word of caution: driving/warming up without exhaust manifold is going to damage your valves since they'll cool too fast.